Release version 3.1.12 (2020.0.12).

See #3734

.github/PULL_REQUEST_TEMPLATE.md

@@ -6,6 +6,7 @@ Make sure that:
 -->
 
 - [ ] You have read the [Spring Data contribution guidelines](https://github.com/spring-projects/spring-data-build/blob/master/CONTRIBUTING.adoc).
+- [ ] There is a ticket in the bug tracker for the project in our [JIRA](https://jira.spring.io/browse/DATAMONGO).
 - [ ] You use the code formatters provided [here](https://github.com/spring-projects/spring-data-build/tree/master/etc/ide) and have them applied to your changes. Don’t submit any formatting related changes.
 - [ ] You submit test cases (unit or integration tests) that back your changes.
 - [ ] You added yourself as author in the headers of the classes you touched. Amend the date range in the Apache license header if needed. For new types, add the license header (copy from another file and set the current year only).

.github/workflows/project.yml

@@ -1,47 +0,0 @@
-# GitHub Actions to automate GitHub issues for Spring Data Project Management
-
-name: Spring Data GitHub Issues
-
-on:
-  issues:
-    types: [opened, edited, reopened]
-  issue_comment:
-    types: [created]
-  pull_request_target:
-    types: [opened, edited, reopened]
-
-jobs:
-  Inbox:
-    runs-on: ubuntu-latest
-    if: github.repository_owner == 'spring-projects' && (github.event.action == 'opened' || github.event.action == 'reopened') && github.event.pull_request == null
-    steps:
-      - name: Create or Update Issue Card
-        uses: peter-evans/create-or-update-project-card@v1.1.2
-        with:
-          project-name: 'Spring Data'
-          column-name: 'Inbox'
-          project-location: 'spring-projects'
-          token: ${{ secrets.GH_ISSUES_TOKEN_SPRING_DATA }}
-  Pull-Request:
-    runs-on: ubuntu-latest
-    if: github.repository_owner == 'spring-projects' && (github.event.action == 'opened' || github.event.action == 'reopened') && github.event.pull_request != null
-    steps:
-      - name: Create or Update Pull Request Card
-        uses: peter-evans/create-or-update-project-card@v1.1.2
-        with:
-          project-name: 'Spring Data'
-          column-name: 'Review pending'
-          project-location: 'spring-projects'
-          issue-number: ${{ github.event.pull_request.number }}
-          token: ${{ secrets.GH_ISSUES_TOKEN_SPRING_DATA }}
-  Feedback-Provided:
-    runs-on: ubuntu-latest
-    if: github.repository_owner == 'spring-projects' && github.event_name == 'issue_comment' && github.event.action == 'created' && github.actor != 'spring-projects-issues' && github.event.pull_request == null && github.event.issue.state == 'open' && contains(toJSON(github.event.issue.labels), 'waiting-for-feedback')
-    steps:
-      - name: Update Project Card
-        uses: peter-evans/create-or-update-project-card@v1.1.2
-        with:
-          project-name: 'Spring Data'
-          column-name: 'Feedback provided'
-          project-location: 'spring-projects'
-          token: ${{ secrets.GH_ISSUES_TOKEN_SPRING_DATA }}

CI.adoc

@@ -1,6 +1,6 @@
 = Continuous Integration
 
-image:https://jenkins.spring.io/buildStatus/icon?job=spring-data-mongodb%2Fmain&subject=Moore%20(main)[link=https://jenkins.spring.io/view/SpringData/job/spring-data-mongodb/]
+image:https://jenkins.spring.io/buildStatus/icon?job=spring-data-mongodb%2Fmaster&subject=Moore%20(master)[link=https://jenkins.spring.io/view/SpringData/job/spring-data-mongodb/]
 image:https://jenkins.spring.io/buildStatus/icon?job=spring-data-mongodb%2F2.1.x&subject=Lovelace%20(2.1.x)[link=https://jenkins.spring.io/view/SpringData/job/spring-data-mongodb/]
 image:https://jenkins.spring.io/buildStatus/icon?job=spring-data-mongodb%2F1.10.x&subject=Ingalls%20(1.10.x)[link=https://jenkins.spring.io/view/SpringData/job/spring-data-mongodb/]
 

CONTRIBUTING.adoc

@@ -1,3 +1,3 @@
 = Spring Data contribution guidelines
 
-You find the contribution guidelines for Spring Data projects https://github.com/spring-projects/spring-data-build/blob/main/CONTRIBUTING.adoc[here].
+You find the contribution guidelines for Spring Data projects https://github.com/spring-projects/spring-data-build/blob/master/CONTRIBUTING.adoc[here].

Jenkinsfile

@@ -3,7 +3,7 @@ pipeline {
 
 	triggers {
 		pollSCM 'H/10 * * * *'
-		upstream(upstreamProjects: "spring-data-commons/main", threshold: hudson.model.Result.SUCCESS)
+		upstream(upstreamProjects: "spring-data-commons/2.4.x", threshold: hudson.model.Result.SUCCESS)
 	}
 
 	options {
@@ -23,39 +23,39 @@ pipeline {
 
 					steps {
 						script {
-							def image = docker.build("springci/spring-data-openjdk8-with-mongodb-4.0.23", "ci/openjdk8-mongodb-4.0/")
+							def image = docker.build("springci/spring-data-openjdk8-with-mongodb-4.0", "ci/openjdk8-mongodb-4.0/")
 							docker.withRegistry('', 'hub.docker.com-springbuildmaster') {
 								image.push()
 							}
 						}
 					}
 				}
-				stage('Publish JDK 8 + MongoDB 4.4') {
+				stage('Publish JDK 8 + MongoDB 4.2') {
 					when {
-						changeset "ci/openjdk8-mongodb-4.4/**"
+						changeset "ci/openjdk8-mongodb-4.2/**"
 					}
 					agent { label 'data' }
 					options { timeout(time: 30, unit: 'MINUTES') }
 
 					steps {
 						script {
-							def image = docker.build("springci/spring-data-openjdk8-with-mongodb-4.4.4", "ci/openjdk8-mongodb-4.4/")
+							def image = docker.build("springci/spring-data-openjdk8-with-mongodb-4.2.0", "ci/openjdk8-mongodb-4.2/")
 							docker.withRegistry('', 'hub.docker.com-springbuildmaster') {
 								image.push()
 							}
 						}
 					}
 				}
-				stage('Publish JDK 16 + MongoDB 4.4') {
+				stage('Publish JDK 15 + MongoDB 4.2') {
 					when {
-						changeset "ci/openjdk16-mongodb-4.4/**"
+						changeset "ci/openjdk15-mongodb-4.2/**"
 					}
 					agent { label 'data' }
 					options { timeout(time: 30, unit: 'MINUTES') }
 
 					steps {
 						script {
-							def image = docker.build("springci/spring-data-openjdk16-with-mongodb-4.4.4", "ci/openjdk16-mongodb-4.4/")
+							def image = docker.build("springci/spring-data-openjdk15-with-mongodb-4.2.0", "ci/openjdk15-mongodb-4.2/")
 							docker.withRegistry('', 'hub.docker.com-springbuildmaster') {
 								image.push()
 							}
@@ -68,7 +68,7 @@ pipeline {
 		stage("test: baseline (jdk8)") {
 			when {
 				anyOf {
-					branch 'main'
+					branch '3.1.x'
 					not { triggeredBy 'UpstreamCause' }
 				}
 			}
@@ -82,7 +82,7 @@ pipeline {
 			steps {
 				script {
 					docker.withRegistry('', 'hub.docker.com-springbuildmaster') {
-						docker.image('springci/spring-data-openjdk8-with-mongodb-4.0.23:latest').inside('-v $HOME:/tmp/jenkins-home') {
+						docker.image('springci/spring-data-openjdk8-with-mongodb-4.2.0:latest').inside('-v $HOME:/tmp/jenkins-home') {
 							sh 'mkdir -p /tmp/mongodb/db /tmp/mongodb/log'
 							sh 'mongod --setParameter transactionLifetimeLimitSeconds=90 --setParameter maxTransactionLockRequestTimeoutMillis=10000 --dbpath /tmp/mongodb/db --replSet rs0 --fork --logpath /tmp/mongodb/log/mongod.log &'
 							sh 'sleep 10'
@@ -98,7 +98,7 @@ pipeline {
 		stage("Test other configurations") {
 			when {
 				allOf {
-					branch 'main'
+					branch '3.1.x'
 					not { triggeredBy 'UpstreamCause' }
 				}
 			}
@@ -114,7 +114,7 @@ pipeline {
 					steps {
 						script {
 							docker.withRegistry('', 'hub.docker.com-springbuildmaster') {
-								docker.image('springci/spring-data-openjdk8-with-mongodb-4.0.23:latest').inside('-v $HOME:/tmp/jenkins-home') {
+								docker.image('springci/spring-data-openjdk8-with-mongodb-4.0:latest').inside('-v $HOME:/tmp/jenkins-home') {
 									sh 'mkdir -p /tmp/mongodb/db /tmp/mongodb/log'
 									sh 'mongod --setParameter transactionLifetimeLimitSeconds=90 --setParameter maxTransactionLockRequestTimeoutMillis=10000 --dbpath /tmp/mongodb/db --replSet rs0 --fork --logpath /tmp/mongodb/log/mongod.log &'
 									sh 'sleep 10'
@@ -127,7 +127,7 @@ pipeline {
 					}
 				}
 
-				stage("test: mongodb 4.4 (jdk8)") {
+				stage("test: mongodb 4.2 (jdk8)") {
 					agent {
 						label 'data'
 					}
@@ -138,7 +138,7 @@ pipeline {
 					steps {
 						script {
 							docker.withRegistry('', 'hub.docker.com-springbuildmaster') {
-								docker.image('springci/spring-data-openjdk8-with-mongodb-4.4.4:latest').inside('-v $HOME:/tmp/jenkins-home') {
+								docker.image('springci/spring-data-openjdk8-with-mongodb-4.2.0:latest').inside('-v $HOME:/tmp/jenkins-home') {
 									sh 'mkdir -p /tmp/mongodb/db /tmp/mongodb/log'
 									sh 'mongod --setParameter transactionLifetimeLimitSeconds=90 --setParameter maxTransactionLockRequestTimeoutMillis=10000 --dbpath /tmp/mongodb/db --replSet rs0 --fork --logpath /tmp/mongodb/log/mongod.log &'
 									sh 'sleep 10'
@@ -151,7 +151,7 @@ pipeline {
 					}
 				}
 
-				stage("test: baseline (jdk16)") {
+				stage("test: baseline (jdk15)") {
 					agent {
 						label 'data'
 					}
@@ -162,7 +162,7 @@ pipeline {
 					steps {
 						script {
 							docker.withRegistry('', 'hub.docker.com-springbuildmaster') {
-								docker.image('springci/spring-data-openjdk16-with-mongodb-4.4.4:latest').inside('-v $HOME:/tmp/jenkins-home') {
+								docker.image('springci/spring-data-openjdk15-with-mongodb-4.2.0:latest').inside('-v $HOME:/tmp/jenkins-home') {
 									sh 'mkdir -p /tmp/mongodb/db /tmp/mongodb/log'
 									sh 'mongod --setParameter transactionLifetimeLimitSeconds=90 --setParameter maxTransactionLockRequestTimeoutMillis=10000 --dbpath /tmp/mongodb/db --replSet rs0 --fork --logpath /tmp/mongodb/log/mongod.log &'
 									sh 'sleep 10'
@@ -180,7 +180,7 @@ pipeline {
 		stage('Release to artifactory') {
 			when {
 				anyOf {
-					branch 'main'
+					branch '3.1.x'
 					not { triggeredBy 'UpstreamCause' }
 				}
 			}
@@ -213,7 +213,7 @@ pipeline {
 
 		stage('Publish documentation') {
 			when {
-				branch 'main'
+				branch '3.1.x'
 			}
 			agent {
 				label 'data'

README.adoc

@@ -1,6 +1,6 @@
 image:https://spring.io/badges/spring-data-mongodb/ga.svg[Spring Data MongoDB,link=https://projects.spring.io/spring-data-mongodb#quick-start] image:https://spring.io/badges/spring-data-mongodb/snapshot.svg[Spring Data MongoDB,link=https://projects.spring.io/spring-data-mongodb#quick-start]
 
-= Spring Data MongoDB image:https://jenkins.spring.io/buildStatus/icon?job=spring-data-mongodb%2Fmain&subject=Build[link=https://jenkins.spring.io/view/SpringData/job/spring-data-mongodb/] https://gitter.im/spring-projects/spring-data[image:https://badges.gitter.im/spring-projects/spring-data.svg[Gitter]]
+= Spring Data MongoDB image:https://jenkins.spring.io/buildStatus/icon?job=spring-data-mongodb%2Fmaster&subject=Build[link=https://jenkins.spring.io/view/SpringData/job/spring-data-mongodb/] https://gitter.im/spring-projects/spring-data[image:https://badges.gitter.im/spring-projects/spring-data.svg[Gitter]]
 
 The primary goal of the https://projects.spring.io/spring-data[Spring Data] project is to make it easier to build Spring-powered applications that use new data access technologies such as non-relational databases, map-reduce frameworks, and cloud based data services.
 

ci/openjdk11-mongodb-4.2/Dockerfile

@@ -5,11 +5,11 @@ ENV DEBIAN_FRONTEND=noninteractive
 
 RUN set -eux; \
 	apt-get update && apt-get install -y apt-transport-https apt-utils gnupg2 ; \
-	apt-key adv --keyserver hkps://keyserver.ubuntu.com:443 --recv 656408E390CFB1F5 ; \
-	echo "deb [ arch=amd64 ] https://repo.mongodb.org/apt/ubuntu bionic/mongodb-org/4.4 multiverse" | tee /etc/apt/sources.list.d/mongodb-org-4.4.list; \
+	apt-key adv --keyserver hkps://keyserver.ubuntu.com:443 --recv e162f504a20cdf15827f718d4b7c549a058f8b6b ; \
+	echo "deb [ arch=amd64 ] https://repo.mongodb.org/apt/ubuntu bionic/mongodb-org/4.2 multiverse" | tee /etc/apt/sources.list.d/mongodb-org-4.2.list; \
 	echo ${TZ} > /etc/timezone;
 
 RUN apt-get update ; \
-	apt-get install -y mongodb-org=4.4.4 mongodb-org-server=4.4.4 mongodb-org-shell=4.4.4 mongodb-org-mongos=4.4.4 mongodb-org-tools=4.4.4 ; \
+	apt-get install -y mongodb-org=4.2.0 mongodb-org-server=4.2.0 mongodb-org-shell=4.2.0 mongodb-org-mongos=4.2.0 mongodb-org-tools=4.2.0 ; \
 	apt-get clean; \
 	rm -rf /var/lib/apt/lists/*;

ci/openjdk15-mongodb-4.2/Dockerfile

@@ -1,15 +1,15 @@
-FROM adoptopenjdk/openjdk16:latest 
+FROM adoptopenjdk/openjdk15:latest
 
 ENV TZ=Etc/UTC
 ENV DEBIAN_FRONTEND=noninteractive
 
 RUN set -eux; \
 	apt-get update && apt-get install -y apt-transport-https apt-utils gnupg2 ; \
-	apt-key adv --keyserver hkps://keyserver.ubuntu.com:443 --recv 656408E390CFB1F5 ; \
-	echo "deb [ arch=amd64 ] https://repo.mongodb.org/apt/ubuntu bionic/mongodb-org/4.4 multiverse" | tee /etc/apt/sources.list.d/mongodb-org-4.4.list; \
+	apt-key adv --keyserver hkps://keyserver.ubuntu.com:443 --recv e162f504a20cdf15827f718d4b7c549a058f8b6b ; \
+	echo "deb [ arch=amd64 ] https://repo.mongodb.org/apt/ubuntu bionic/mongodb-org/4.2 multiverse" | tee /etc/apt/sources.list.d/mongodb-org-4.2.list; \
 	echo ${TZ} > /etc/timezone;
 
 RUN apt-get update ; \
-	apt-get install -y mongodb-org=4.4.4 mongodb-org-server=4.4.4 mongodb-org-shell=4.4.4 mongodb-org-mongos=4.4.4 mongodb-org-tools=4.4.4 ; \
+	apt-get install -y mongodb-org=4.2.0 mongodb-org-server=4.2.0 mongodb-org-shell=4.2.0 mongodb-org-mongos=4.2.0 mongodb-org-tools=4.2.0 ; \
 	apt-get clean; \
 	rm -rf /var/lib/apt/lists/*;

ci/openjdk8-mongodb-4.0/Dockerfile

@@ -10,6 +10,6 @@ RUN RUN set -eux; \
 	echo ${TZ} > /etc/timezone;
 
 RUN apt-get update ; \
-	apt-get install -y mongodb-org=4.0.23 mongodb-org-server=4.0.23 mongodb-org-shell=4.0.23 mongodb-org-mongos=4.0.23 mongodb-org-tools=4.0.23 ; \
+	apt-get install -y mongodb-org=4.0.14 mongodb-org-server=4.0.14 mongodb-org-shell=4.0.14 mongodb-org-mongos=4.0.14 mongodb-org-tools=4.0.14 ; \
 	apt-get clean; \
 	rm -rf /var/lib/apt/lists/*;

ci/openjdk8-mongodb-4.2/Dockerfile

@@ -5,13 +5,11 @@ ENV DEBIAN_FRONTEND=noninteractive
 
 RUN set -eux; \
 	apt-get update && apt-get install -y apt-transport-https apt-utils gnupg2 ; \
-	apt-key adv --keyserver hkps://keyserver.ubuntu.com:443 --recv 656408E390CFB1F5 ; \
-	echo "deb [ arch=amd64 ] https://repo.mongodb.org/apt/ubuntu bionic/mongodb-org/4.4 multiverse" | tee /etc/apt/sources.list.d/mongodb-org-4.4.list; \
+	apt-key adv --keyserver hkps://keyserver.ubuntu.com:443 --recv e162f504a20cdf15827f718d4b7c549a058f8b6b ; \
+	echo "deb [ arch=amd64 ] https://repo.mongodb.org/apt/ubuntu bionic/mongodb-org/4.2 multiverse" | tee /etc/apt/sources.list.d/mongodb-org-4.2.list; \
 	echo ${TZ} > /etc/timezone;
 
 RUN apt-get update ; \
-	ln -T /bin/true /usr/bin/systemctl ; \
-	apt-get install -y mongodb-org=4.4.4 mongodb-org-server=4.4.4 mongodb-org-shell=4.4.4 mongodb-org-mongos=4.4.4 mongodb-org-tools=4.4.4 ; \
-	rm /usr/bin/systemctl ; \
+	apt-get install -y mongodb-org=4.2.0 mongodb-org-server=4.2.0 mongodb-org-shell=4.2.0 mongodb-org-mongos=4.2.0 mongodb-org-tools=4.2.0 ; \
 	apt-get clean; \
 	rm -rf /var/lib/apt/lists/*;

pom.xml

@@ -5,7 +5,7 @@
 
 	<groupId>org.springframework.data</groupId>
 	<artifactId>spring-data-mongodb-parent</artifactId>
-	<version>3.3.0-M2</version>
+	<version>3.1.12</version>
 	<packaging>pom</packaging>
 
 	<name>Spring Data MongoDB</name>
@@ -15,7 +15,7 @@
 	<parent>
 		<groupId>org.springframework.data.build</groupId>
 		<artifactId>spring-data-parent</artifactId>
-		<version>2.6.0-M2</version>
+		<version>2.4.12</version>
 	</parent>
 
 	<modules>
@@ -26,8 +26,8 @@
 	<properties>
 		<project.type>multi</project.type>
 		<dist.id>spring-data-mongodb</dist.id>
-		<springdata.commons>2.6.0-M2</springdata.commons>
-		<mongo>4.3.0</mongo>
+		<springdata.commons>2.4.12</springdata.commons>
+		<mongo>4.1.2</mongo>
 		<mongo.reactivestreams>${mongo}</mongo.reactivestreams>
 		<jmh.version>1.19</jmh.version>
 	</properties>
@@ -134,8 +134,8 @@
 
 	<repositories>
 		<repository>
-			<id>spring-libs-milestone</id>
-			<url>https://repo.spring.io/libs-milestone</url>
+			<id>spring-libs-release</id>
+			<url>https://repo.spring.io/libs-release</url>
 		</repository>
 		<repository>
 			<id>sonatype-libs-snapshot</id>

spring-data-mongodb-benchmarks/pom.xml

@@ -7,7 +7,7 @@
 	<parent>
 		<groupId>org.springframework.data</groupId>
 		<artifactId>spring-data-mongodb-parent</artifactId>
-		<version>3.3.0-M2</version>
+		<version>3.1.12</version>
 		<relativePath>../pom.xml</relativePath>
 	</parent>
 

spring-data-mongodb-distribution/pom.xml

@@ -14,7 +14,7 @@
 	<parent>
 		<groupId>org.springframework.data</groupId>
 		<artifactId>spring-data-mongodb-parent</artifactId>
-		<version>3.3.0-M2</version>
+		<version>3.1.12</version>
 		<relativePath>../pom.xml</relativePath>
 	</parent>
 

spring-data-mongodb/pom.xml

@@ -11,7 +11,7 @@
 	<parent>
 		<groupId>org.springframework.data</groupId>
 		<artifactId>spring-data-mongodb-parent</artifactId>
-		<version>3.3.0-M2</version>
+		<version>3.1.12</version>
 		<relativePath>../pom.xml</relativePath>
 	</parent>
 
@@ -87,13 +87,6 @@
 			<optional>true</optional>
 		</dependency>
 
-		<dependency>
-			<groupId>com.google.code.findbugs</groupId>
-			<artifactId>jsr305</artifactId>
-			<version>3.0.2</version>
-			<optional>true</optional>
-		</dependency>
-
 		<!-- reactive -->
 
 		<dependency>

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/BindableMongoExpression.java

@@ -1,152 +0,0 @@
-/*
- * Copyright 2021 the original author or authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      https://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.springframework.data.mongodb;
-
-import java.util.Arrays;
-
-import org.bson.Document;
-import org.bson.codecs.DocumentCodec;
-import org.bson.codecs.configuration.CodecRegistry;
-import org.springframework.data.mongodb.util.json.ParameterBindingDocumentCodec;
-import org.springframework.data.util.Lazy;
-import org.springframework.lang.Nullable;
-import org.springframework.util.ObjectUtils;
-import org.springframework.util.StringUtils;
-
-/**
- * A {@link MongoExpression} using the {@link ParameterBindingDocumentCodec} for parsing a raw ({@literal json})
- * expression. The expression will be wrapped within <code>{ ... }</code> if necessary. The actual parsing and parameter
- * binding of placeholders like {@code ?0} is delayed upon first call on the the target {@link Document} via
- * {@link #toDocument()}.
- * <p />
- *
- * <pre class="code">
- * $toUpper : $name                -> { '$toUpper' : '$name' }
- *
- * { '$toUpper' : '$name' }        -> { '$toUpper' : '$name' }
- *
- * { '$toUpper' : '?0' }, "$name"  -> { '$toUpper' : '$name' }
- * </pre>
- *
- * Some types might require a special {@link org.bson.codecs.Codec}. If so, make sure to provide a {@link CodecRegistry}
- * containing the required {@link org.bson.codecs.Codec codec} via {@link #withCodecRegistry(CodecRegistry)}.
- *
- * @author Christoph Strobl
- * @since 3.2
- */
-public class BindableMongoExpression implements MongoExpression {
-
-	private final String expressionString;
-
-	private final @Nullable CodecRegistryProvider codecRegistryProvider;
-
-	private final @Nullable Object[] args;
-
-	private final Lazy<Document> target;
-
-	/**
-	 * Create a new instance of {@link BindableMongoExpression}.
-	 *
-	 * @param expression must not be {@literal null}.
-	 * @param args can be {@literal null}.
-	 */
-	public BindableMongoExpression(String expression, @Nullable Object[] args) {
-		this(expression, null, args);
-	}
-
-	/**
-	 * Create a new instance of {@link BindableMongoExpression}.
-	 *
-	 * @param expression must not be {@literal null}.
-	 * @param codecRegistryProvider can be {@literal null}.
-	 * @param args can be {@literal null}.
-	 */
-	public BindableMongoExpression(String expression, @Nullable CodecRegistryProvider codecRegistryProvider,
-			@Nullable Object[] args) {
-
-		this.expressionString = expression;
-		this.codecRegistryProvider = codecRegistryProvider;
-		this.args = args;
-		this.target = Lazy.of(this::parse);
-	}
-
-	/**
-	 * Provide the {@link CodecRegistry} used to convert expressions.
-	 *
-	 * @param codecRegistry must not be {@literal null}.
-	 * @return new instance of {@link BindableMongoExpression}.
-	 */
-	public BindableMongoExpression withCodecRegistry(CodecRegistry codecRegistry) {
-		return new BindableMongoExpression(expressionString, () -> codecRegistry, args);
-	}
-
-	/**
-	 * Provide the arguments to bind to the placeholders via their index.
-	 *
-	 * @param args must not be {@literal null}.
-	 * @return new instance of {@link BindableMongoExpression}.
-	 */
-	public BindableMongoExpression bind(Object... args) {
-		return new BindableMongoExpression(expressionString, codecRegistryProvider, args);
-	}
-
-	/*
-	 * (non-Javadoc)
-	 * @see org.springframework.data.mongodb.MongoExpression#toDocument()
-	 */
-	@Override
-	public Document toDocument() {
-		return target.get();
-	}
-
-	/*
-	 * (non-Javadoc)
-	 * @see java.lang.Object#toString()
-	 */
-	@Override
-	public String toString() {
-		return "BindableMongoExpression{" + "expressionString='" + expressionString + '\'' + ", args="
-				+ Arrays.toString(args) + '}';
-	}
-
-	private Document parse() {
-
-		String expression = wrapJsonIfNecessary(expressionString);
-
-		if (ObjectUtils.isEmpty(args)) {
-
-			if (codecRegistryProvider == null) {
-				return Document.parse(expression);
-			}
-
-			return Document.parse(expression, codecRegistryProvider.getCodecFor(Document.class)
-					.orElseGet(() -> new DocumentCodec(codecRegistryProvider.getCodecRegistry())));
-		}
-
-		ParameterBindingDocumentCodec codec = codecRegistryProvider == null ? new ParameterBindingDocumentCodec()
-				: new ParameterBindingDocumentCodec(codecRegistryProvider.getCodecRegistry());
-		return codec.decode(expression, args);
-	}
-
-	private static String wrapJsonIfNecessary(String json) {
-
-		if (StringUtils.hasText(json) && (json.startsWith("{") && json.endsWith("}"))) {
-			return json;
-		}
-
-		return "{" + json + "}";
-	}
-}

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/MongoExpression.java

@@ -1,73 +0,0 @@
-/*
- * Copyright 2021 the original author or authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      https://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.springframework.data.mongodb;
-
-/**
- * Wrapper object for MongoDB expressions like {@code $toUpper : $name} that manifest as {@link org.bson.Document} when
- * passed on to the driver.
- * <p />
- * A set of predefined {@link MongoExpression expressions}, including a
- * {@link org.springframework.data.mongodb.core.aggregation.AggregationSpELExpression SpEL based variant} for method
- * like expressions (eg. {@code toUpper(name)}) are available via the
- * {@link org.springframework.data.mongodb.core.aggregation Aggregation API}.
- *
- * @author Christoph Strobl
- * @since 3.2
- * @see org.springframework.data.mongodb.core.aggregation.ArithmeticOperators
- * @see org.springframework.data.mongodb.core.aggregation.ArrayOperators
- * @see org.springframework.data.mongodb.core.aggregation.ComparisonOperators
- * @see org.springframework.data.mongodb.core.aggregation.ConditionalOperators
- * @see org.springframework.data.mongodb.core.aggregation.ConvertOperators
- * @see org.springframework.data.mongodb.core.aggregation.DateOperators
- * @see org.springframework.data.mongodb.core.aggregation.ObjectOperators
- * @see org.springframework.data.mongodb.core.aggregation.SetOperators
- * @see org.springframework.data.mongodb.core.aggregation.StringOperators
- */
-@FunctionalInterface
-public interface MongoExpression {
-
-	/**
-	 * Create a new {@link MongoExpression} from plain {@link String} (eg. {@code $toUpper : $name}). <br />
-	 * The given expression will be wrapped with <code>{ ... }</code> to match an actual MongoDB {@link org.bson.Document}
-	 * if necessary.
-	 *
-	 * @param expression must not be {@literal null}.
-	 * @return new instance of {@link MongoExpression}.
-	 */
-	static MongoExpression create(String expression) {
-		return new BindableMongoExpression(expression, null);
-	}
-
-	/**
-	 * Create a new {@link MongoExpression} from plain {@link String} containing placeholders (eg. {@code $toUpper : ?0})
-	 * that will be resolved on first call of {@link #toDocument()}. <br />
-	 * The given expression will be wrapped with <code>{ ... }</code> to match an actual MongoDB {@link org.bson.Document}
-	 * if necessary.
-	 *
-	 * @param expression must not be {@literal null}.
-	 * @return new instance of {@link MongoExpression}.
-	 */
-	static MongoExpression create(String expression, Object... args) {
-		return new BindableMongoExpression(expression, args);
-	}
-
-	/**
-	 * Obtain the native {@link org.bson.Document} representation.
-	 *
-	 * @return never {@literal null}.
-	 */
-	org.bson.Document toDocument();
-}

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/AggregationUtil.java

@@ -27,7 +27,6 @@ import org.springframework.data.mongodb.core.aggregation.Aggregation;
 import org.springframework.data.mongodb.core.aggregation.AggregationOperation;
 import org.springframework.data.mongodb.core.aggregation.AggregationOperationContext;
 import org.springframework.data.mongodb.core.aggregation.AggregationOptions;
-import org.springframework.data.mongodb.core.aggregation.AggregationOptions.DomainTypeMapping;
 import org.springframework.data.mongodb.core.aggregation.CountOperation;
 import org.springframework.data.mongodb.core.aggregation.RelaxedTypeBasedAggregationOperationContext;
 import org.springframework.data.mongodb.core.aggregation.TypeBasedAggregationOperationContext;
@@ -37,7 +36,6 @@ import org.springframework.data.mongodb.core.mapping.MongoPersistentEntity;
 import org.springframework.data.mongodb.core.mapping.MongoPersistentProperty;
 import org.springframework.data.mongodb.core.query.CriteriaDefinition;
 import org.springframework.data.mongodb.core.query.Query;
-import org.springframework.data.util.Lazy;
 import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 import org.springframework.util.ObjectUtils;
@@ -54,46 +52,41 @@ class AggregationUtil {
 
 	QueryMapper queryMapper;
 	MappingContext<? extends MongoPersistentEntity<?>, MongoPersistentProperty> mappingContext;
-	Lazy<AggregationOperationContext> untypedMappingContext;
 
 	AggregationUtil(QueryMapper queryMapper,
 			MappingContext<? extends MongoPersistentEntity<?>, MongoPersistentProperty> mappingContext) {
 
 		this.queryMapper = queryMapper;
 		this.mappingContext = mappingContext;
-		this.untypedMappingContext = Lazy
-				.of(() -> new RelaxedTypeBasedAggregationOperationContext(Object.class, mappingContext, queryMapper));
 	}
 
-	AggregationOperationContext createAggregationContext(Aggregation aggregation, @Nullable Class<?> inputType) {
+	/**
+	 * Prepare the {@link AggregationOperationContext} for a given aggregation by either returning the context itself it
+	 * is not {@literal null}, create a {@link TypeBasedAggregationOperationContext} if the aggregation contains type
+	 * information (is a {@link TypedAggregation}) or use the {@link Aggregation#DEFAULT_CONTEXT}.
+	 *
+	 * @param aggregation must not be {@literal null}.
+	 * @param context can be {@literal null}.
+	 * @return the root {@link AggregationOperationContext} to use.
+	 */
+	AggregationOperationContext prepareAggregationContext(Aggregation aggregation,
+			@Nullable AggregationOperationContext context) {
 
-		DomainTypeMapping domainTypeMapping = aggregation.getOptions().getDomainTypeMapping();
-
-		if (domainTypeMapping == DomainTypeMapping.NONE) {
-			return Aggregation.DEFAULT_CONTEXT;
+		if (context != null) {
+			return context;
 		}
 
 		if (!(aggregation instanceof TypedAggregation)) {
+			return new RelaxedTypeBasedAggregationOperationContext(Object.class, mappingContext, queryMapper);
+		}
 
-			if(inputType == null) {
-				return untypedMappingContext.get();
-			}
-
-			if (domainTypeMapping == DomainTypeMapping.STRICT
-					&& !aggregation.getPipeline().containsUnionWith()) {
-				return new TypeBasedAggregationOperationContext(inputType, mappingContext, queryMapper);
-			}
+		Class<?> inputType = ((TypedAggregation) aggregation).getInputType();
 
+		if (aggregation.getPipeline().containsUnionWith()) {
 			return new RelaxedTypeBasedAggregationOperationContext(inputType, mappingContext, queryMapper);
 		}
 
-		inputType = ((TypedAggregation<?>) aggregation).getInputType();
-		if (domainTypeMapping == DomainTypeMapping.STRICT
-				&& !aggregation.getPipeline().containsUnionWith()) {
-			return new TypeBasedAggregationOperationContext(inputType, mappingContext, queryMapper);
-		}
-
-		return new RelaxedTypeBasedAggregationOperationContext(inputType, mappingContext, queryMapper);
+		return new TypeBasedAggregationOperationContext(inputType, mappingContext, queryMapper);
 	}
 
 	/**
@@ -132,6 +125,53 @@ class AggregationUtil {
 		return command;
 	}
 
+	/**
+	 * Create a {@code $count} aggregation for {@link Query} and optionally a {@link Class entity class}.
+	 *
+	 * @param query must not be {@literal null}.
+	 * @param entityClass can be {@literal null} if the {@link Query} object is empty.
+	 * @return the {@link Aggregation} pipeline definition to run a {@code $count} aggregation.
+	 */
+	Aggregation createCountAggregation(Query query, @Nullable Class<?> entityClass) {
+
+		List<AggregationOperation> pipeline = computeCountAggregationPipeline(query, entityClass);
+
+		Aggregation aggregation = entityClass != null ? Aggregation.newAggregation(entityClass, pipeline)
+				: Aggregation.newAggregation(pipeline);
+		aggregation.withOptions(AggregationOptions.builder().collation(query.getCollation().orElse(null)).build());
+
+		return aggregation;
+	}
+
+	private List<AggregationOperation> computeCountAggregationPipeline(Query query, @Nullable Class<?> entityType) {
+
+		CountOperation count = Aggregation.count().as("totalEntityCount");
+		if (query.getQueryObject().isEmpty()) {
+			return Collections.singletonList(count);
+		}
+
+		Assert.notNull(entityType, "Entity type must not be null!");
+
+		Document mappedQuery = queryMapper.getMappedObject(query.getQueryObject(),
+				mappingContext.getPersistentEntity(entityType));
+
+		CriteriaDefinition criteria = new CriteriaDefinition() {
+
+			@Override
+			public Document getCriteriaObject() {
+				return mappedQuery;
+			}
+
+			@Nullable
+			@Override
+			public String getKey() {
+				return null;
+			}
+		};
+
+		return Arrays.asList(Aggregation.match(criteria), count);
+	}
+
 	private List<Document> mapAggregationPipeline(List<Document> pipeline) {
 
 		return pipeline.stream().map(val -> queryMapper.getMappedObject(val, Optional.empty()))

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/CollectionOptions.java

@@ -17,11 +17,8 @@ package org.springframework.data.mongodb.core;
 
 import java.util.Optional;
 
-import org.springframework.data.mongodb.core.mapping.Field;
 import org.springframework.data.mongodb.core.query.Collation;
 import org.springframework.data.mongodb.core.schema.MongoJsonSchema;
-import org.springframework.data.mongodb.core.timeseries.Granularity;
-import org.springframework.data.mongodb.core.timeseries.GranularityDefinition;
 import org.springframework.data.mongodb.core.validation.Validator;
 import org.springframework.data.util.Optionals;
 import org.springframework.lang.Nullable;
@@ -45,7 +42,6 @@ public class CollectionOptions {
 	private @Nullable Boolean capped;
 	private @Nullable Collation collation;
 	private ValidationOptions validationOptions;
-	private @Nullable TimeSeriesOptions timeSeriesOptions;
 
 	/**
 	 * Constructs a new <code>CollectionOptions</code> instance.
@@ -58,19 +54,17 @@ public class CollectionOptions {
 	 */
 	@Deprecated
 	public CollectionOptions(@Nullable Long size, @Nullable Long maxDocuments, @Nullable Boolean capped) {
-		this(size, maxDocuments, capped, null, ValidationOptions.none(), null);
+		this(size, maxDocuments, capped, null, ValidationOptions.none());
 	}
 
 	private CollectionOptions(@Nullable Long size, @Nullable Long maxDocuments, @Nullable Boolean capped,
-			@Nullable Collation collation, ValidationOptions validationOptions,
-			@Nullable TimeSeriesOptions timeSeriesOptions) {
+			@Nullable Collation collation, ValidationOptions validationOptions) {
 
 		this.maxDocuments = maxDocuments;
 		this.size = size;
 		this.capped = capped;
 		this.collation = collation;
 		this.validationOptions = validationOptions;
-		this.timeSeriesOptions = timeSeriesOptions;
 	}
 
 	/**
@@ -84,7 +78,7 @@ public class CollectionOptions {
 
 		Assert.notNull(collation, "Collation must not be null!");
 
-		return new CollectionOptions(null, null, null, collation, ValidationOptions.none(), null);
+		return new CollectionOptions(null, null, null, collation, ValidationOptions.none());
 	}
 
 	/**
@@ -94,21 +88,7 @@ public class CollectionOptions {
 	 * @since 2.0
 	 */
 	public static CollectionOptions empty() {
-		return new CollectionOptions(null, null, null, null, ValidationOptions.none(), null);
-	}
-
-	/**
-	 * Quick way to set up {@link CollectionOptions} for a Time Series collection. For more advanced settings use
-	 * {@link #timeSeries(TimeSeriesOptions)}.
-	 *
-	 * @param timeField The name of the property which contains the date in each time series document. Must not be
-	 *          {@literal null}.
-	 * @return new instance of {@link CollectionOptions}.
-	 * @see #timeSeries(TimeSeriesOptions)
-	 * @since 3.3
-	 */
-	public static CollectionOptions timeSeries(String timeField) {
-		return empty().timeSeries(TimeSeriesOptions.timeSeries(timeField));
+		return new CollectionOptions(null, null, null, null, ValidationOptions.none());
 	}
 
 	/**
@@ -119,7 +99,7 @@ public class CollectionOptions {
 	 * @since 2.0
 	 */
 	public CollectionOptions capped() {
-		return new CollectionOptions(size, maxDocuments, true, collation, validationOptions, null);
+		return new CollectionOptions(size, maxDocuments, true, collation, validationOptions);
 	}
 
 	/**
@@ -130,7 +110,7 @@ public class CollectionOptions {
 	 * @since 2.0
 	 */
 	public CollectionOptions maxDocuments(long maxDocuments) {
-		return new CollectionOptions(size, maxDocuments, capped, collation, validationOptions, timeSeriesOptions);
+		return new CollectionOptions(size, maxDocuments, capped, collation, validationOptions);
 	}
 
 	/**
@@ -141,7 +121,7 @@ public class CollectionOptions {
 	 * @since 2.0
 	 */
 	public CollectionOptions size(long size) {
-		return new CollectionOptions(size, maxDocuments, capped, collation, validationOptions, timeSeriesOptions);
+		return new CollectionOptions(size, maxDocuments, capped, collation, validationOptions);
 	}
 
 	/**
@@ -152,7 +132,7 @@ public class CollectionOptions {
 	 * @since 2.0
 	 */
 	public CollectionOptions collation(@Nullable Collation collation) {
-		return new CollectionOptions(size, maxDocuments, capped, collation, validationOptions, timeSeriesOptions);
+		return new CollectionOptions(size, maxDocuments, capped, collation, validationOptions);
 	}
 
 	/**
@@ -272,20 +252,7 @@ public class CollectionOptions {
 	public CollectionOptions validation(ValidationOptions validationOptions) {
 
 		Assert.notNull(validationOptions, "ValidationOptions must not be null!");
-		return new CollectionOptions(size, maxDocuments, capped, collation, validationOptions, timeSeriesOptions);
-	}
-
-	/**
-	 * Create new {@link CollectionOptions} with the given {@link TimeSeriesOptions}.
-	 *
-	 * @param timeSeriesOptions must not be {@literal null}.
-	 * @return new instance of {@link CollectionOptions}.
-	 * @since 3.3
-	 */
-	public CollectionOptions timeSeries(TimeSeriesOptions timeSeriesOptions) {
-
-		Assert.notNull(timeSeriesOptions, "TimeSeriesOptions must not be null!");
-		return new CollectionOptions(size, maxDocuments, capped, collation, validationOptions, timeSeriesOptions);
+		return new CollectionOptions(size, maxDocuments, capped, collation, validationOptions);
 	}
 
 	/**
@@ -336,16 +303,6 @@ public class CollectionOptions {
 		return validationOptions.isEmpty() ? Optional.empty() : Optional.of(validationOptions);
 	}
 
-	/**
-	 * Get the {@link TimeSeriesOptions} if available.
-	 *
-	 * @return {@link Optional#empty()} if not specified.
-	 * @since 3.3
-	 */
-	public Optional<TimeSeriesOptions> getTimeSeriesOptions() {
-		return Optional.ofNullable(timeSeriesOptions);
-	}
-
 	/**
 	 * Encapsulation of ValidationOptions options.
 	 *
@@ -441,89 +398,4 @@ public class CollectionOptions {
 			return !Optionals.isAnyPresent(getValidator(), getValidationAction(), getValidationLevel());
 		}
 	}
-
-	/**
-	 * Options applicable to Time Series collections.
-	 *
-	 * @author Christoph Strobl
-	 * @since 3.3
-	 * @see <a href=
-	 *      "https://docs.mongodb.com/manual/core/timeseries-collections">https://docs.mongodb.com/manual/core/timeseries-collections</a>
-	 */
-	public static class TimeSeriesOptions {
-
-		private final String timeField;
-
-		private @Nullable final String metaField;
-
-		private final GranularityDefinition granularity;
-
-		private TimeSeriesOptions(String timeField, @Nullable String metaField, GranularityDefinition granularity) {
-
-			Assert.hasText(timeField, "Time field must not be empty or null!");
-
-			this.timeField = timeField;
-			this.metaField = metaField;
-			this.granularity = granularity;
-		}
-
-		/**
-		 * Create a new instance of {@link TimeSeriesOptions} using the given field as its {@literal timeField}. The one,
-		 * that contains the date in each time series document. <br />
-		 * {@link Field#name() Annotated fieldnames} will be considered during the mapping process.
-		 *
-		 * @param timeField must not be {@literal null}.
-		 * @return new instance of {@link TimeSeriesOptions}.
-		 */
-		public static TimeSeriesOptions timeSeries(String timeField) {
-			return new TimeSeriesOptions(timeField, null, Granularity.DEFAULT);
-		}
-
-		/**
-		 * Set the name of the field which contains metadata in each time series document. Should not be the {@literal id}
-		 * nor {@link TimeSeriesOptions#timeSeries(String)} timeField} nor point to an {@literal array} or
-		 * {@link java.util.Collection}. <br />
-		 * {@link Field#name() Annotated fieldnames} will be considered during the mapping process.
-		 *
-		 * @param metaField must not be {@literal null}.
-		 * @return new instance of {@link TimeSeriesOptions}.
-		 */
-		public TimeSeriesOptions metaField(String metaField) {
-			return new TimeSeriesOptions(timeField, metaField, granularity);
-		}
-
-		/**
-		 * Select the {@link GranularityDefinition} parameter to define how data in the time series collection is organized.
-		 * Select one that is closest to the time span between incoming measurements.
-		 *
-		 * @return new instance of {@link TimeSeriesOptions}.
-		 * @see Granularity
-		 */
-		public TimeSeriesOptions granularity(GranularityDefinition granularity) {
-			return new TimeSeriesOptions(timeField, metaField, granularity);
-		}
-
-		/**
-		 * @return never {@literal null}.
-		 */
-		public String getTimeField() {
-			return timeField;
-		}
-
-		/**
-		 * @return can be {@literal null}. Might be an {@literal empty} {@link String} as well, so maybe check via
-		 *         {@link org.springframework.util.StringUtils#hasText(String)}.
-		 */
-		@Nullable
-		public String getMetaField() {
-			return metaField;
-		}
-
-		/**
-		 * @return never {@literal null}.
-		 */
-		public GranularityDefinition getGranularity() {
-			return granularity;
-		}
-	}
 }

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/DefaultIndexOperationsProvider.java

@@ -47,7 +47,7 @@ class DefaultIndexOperationsProvider implements IndexOperationsProvider {
 	 * @see org.springframework.data.mongodb.core.index.IndexOperationsProvider#reactiveIndexOps(java.lang.String)
 	 */
 	@Override
-	public IndexOperations indexOps(String collectionName, Class<?> type) {
-		return new DefaultIndexOperations(mongoDbFactory, collectionName, mapper, type);
+	public IndexOperations indexOps(String collectionName) {
+		return new DefaultIndexOperations(mongoDbFactory, collectionName, mapper);
 	}
 }

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/EntityOperations.java

@@ -16,7 +16,6 @@
 package org.springframework.data.mongodb.core;
 
 import java.util.Collection;
-import java.util.Iterator;
 import java.util.Map;
 import java.util.Optional;
 
@@ -29,23 +28,18 @@ import org.springframework.data.mapping.PersistentEntity;
 import org.springframework.data.mapping.PersistentPropertyAccessor;
 import org.springframework.data.mapping.context.MappingContext;
 import org.springframework.data.mapping.model.ConvertingPropertyAccessor;
-import org.springframework.data.mongodb.core.CollectionOptions.TimeSeriesOptions;
 import org.springframework.data.mongodb.core.convert.MongoWriter;
 import org.springframework.data.mongodb.core.mapping.MongoPersistentEntity;
 import org.springframework.data.mongodb.core.mapping.MongoPersistentProperty;
 import org.springframework.data.mongodb.core.mapping.MongoSimpleTypes;
-import org.springframework.data.mongodb.core.mapping.TimeSeries;
 import org.springframework.data.mongodb.core.query.Collation;
 import org.springframework.data.mongodb.core.query.Criteria;
 import org.springframework.data.mongodb.core.query.Query;
-import org.springframework.data.mongodb.core.timeseries.Granularity;
 import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 import org.springframework.util.ClassUtils;
 import org.springframework.util.LinkedMultiValueMap;
 import org.springframework.util.MultiValueMap;
-import org.springframework.util.ObjectUtils;
-import org.springframework.util.StringUtils;
 
 /**
  * Common operations performed on an entity in the context of it's mapping metadata.
@@ -113,20 +107,6 @@ class EntityOperations {
 		return AdaptibleMappedEntity.of(entity, context, conversionService);
 	}
 
-	/**
-	 * @param source can be {@literal null}.
-	 * @return {@literal true} if the given value is an {@literal array}, {@link Collection} or {@link Iterator}.
-	 * @since 3.2
-	 */
-	static boolean isCollectionLike(@Nullable Object source) {
-
-		if (source == null) {
-			return false;
-		}
-
-		return ObjectUtils.isArray(source) || source instanceof Collection || source instanceof Iterator;
-	}
-
 	/**
 	 * @param entityClass should not be null.
 	 * @return the {@link MongoPersistentEntity#getCollection() collection name}.
@@ -782,24 +762,6 @@ class EntityOperations {
 		 * @return
 		 */
 		Optional<Collation> getCollation(Query query);
-
-		/**
-		 * Derive the applicable {@link CollectionOptions} for the given type.
-		 *
-		 * @return never {@literal null}.
-		 * @since 3.3
-		 */
-		CollectionOptions getCollectionOptions();
-
-		/**
-		 * Map the fields of a given {@link TimeSeriesOptions} against the target domain type to consider potentially
-		 * annotated field names.
-		 *
-		 * @param options must not be {@literal null}.
-		 * @return never {@literal null}.
-		 * @since 3.3
-		 */
-		TimeSeriesOptions mapTimeSeriesOptions(TimeSeriesOptions options);
 	}
 
 	/**
@@ -839,16 +801,6 @@ class EntityOperations {
 
 			return query.getCollation();
 		}
-
-		@Override
-		public CollectionOptions getCollectionOptions() {
-			return CollectionOptions.empty();
-		}
-
-		@Override
-		public TimeSeriesOptions mapTimeSeriesOptions(TimeSeriesOptions options) {
-			return options;
-		}
 	}
 
 	/**
@@ -886,58 +838,6 @@ class EntityOperations {
 
 			return Optional.ofNullable(entity.getCollation());
 		}
-
-		@Override
-		public CollectionOptions getCollectionOptions() {
-
-			CollectionOptions collectionOptions = CollectionOptions.empty();
-			if (entity.hasCollation()) {
-				collectionOptions = collectionOptions.collation(entity.getCollation());
-			}
-
-			if (entity.isAnnotationPresent(TimeSeries.class)) {
-
-				TimeSeries timeSeries = entity.getRequiredAnnotation(TimeSeries.class);
-
-				if (entity.getPersistentProperty(timeSeries.timeField()) == null) {
-					throw new MappingException(String.format("Time series field '%s' does not exist in type %s",
-							timeSeries.timeField(), entity.getName()));
-				}
-
-				TimeSeriesOptions options = TimeSeriesOptions.timeSeries(timeSeries.timeField());
-				if (StringUtils.hasText(timeSeries.metaField())) {
-
-					if (entity.getPersistentProperty(timeSeries.metaField()) == null) {
-						throw new MappingException(
-								String.format("Meta field '%s' does not exist in type %s", timeSeries.metaField(), entity.getName()));
-					}
-
-					options = options.metaField(timeSeries.metaField());
-				}
-				if (!Granularity.DEFAULT.equals(timeSeries.granularity())) {
-					options = options.granularity(timeSeries.granularity());
-				}
-				collectionOptions = collectionOptions.timeSeries(options);
-			}
-
-			return collectionOptions;
-		}
-
-		@Override
-		public TimeSeriesOptions mapTimeSeriesOptions(TimeSeriesOptions source) {
-
-			TimeSeriesOptions target = TimeSeriesOptions.timeSeries(mappedNameOrDefault(source.getTimeField()));
-
-			if (StringUtils.hasText(source.getMetaField())) {
-				target = target.metaField(mappedNameOrDefault(source.getMetaField()));
-			}
-			return target.granularity(source.getGranularity());
-		}
-
-		private String mappedNameOrDefault(String name) {
-			MongoPersistentProperty persistentProperty = entity.getPersistentProperty(name);
-			return persistentProperty != null ? persistentProperty.getFieldName() : name;
-		}
 	}
 
 }

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/IndexConverters.java

@@ -115,10 +115,6 @@ abstract class IndexConverters {
 				ops = ops.collation(fromDocument(indexOptions.get("collation", Document.class)));
 			}
 
-			if (indexOptions.containsKey("wildcardProjection")) {
-				ops.wildcardProjection(indexOptions.get("wildcardProjection", Document.class));
-			}
-
 			return ops;
 		};
 	}

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/MongoOperations.java

@@ -1258,13 +1258,11 @@ public interface MongoOperations extends FluentMongoOperations {
 	 * <a href="https://docs.spring.io/spring/docs/current/spring-framework-reference/core.html#validation" > Spring's
 	 * Type Conversion"</a> for more details.
 	 * <p/>
-	 * Insert is used to initially store the object into the database. To update an existing object use the save method.
 	 * <p/>
-	 * The {@code objectToSave} must not be collection-like.
+	 * Insert is used to initially store the object into the database. To update an existing object use the save method.
 	 *
 	 * @param objectToSave the object to store in the collection. Must not be {@literal null}.
 	 * @return the inserted object.
-	 * @throws IllegalArgumentException in case the {@code objectToSave} is collection-like.
 	 */
 	<T> T insert(T objectToSave);
 
@@ -1275,13 +1273,10 @@ public interface MongoOperations extends FluentMongoOperations {
 	 * configured otherwise, an instance of {@link MappingMongoConverter} will be used.
 	 * <p/>
 	 * Insert is used to initially store the object into the database. To update an existing object use the save method.
-	 * <p/>
-	 * The {@code objectToSave} must not be collection-like.
 	 *
 	 * @param objectToSave the object to store in the collection. Must not be {@literal null}.
 	 * @param collectionName name of the collection to store the object in. Must not be {@literal null}.
 	 * @return the inserted object.
-	 * @throws IllegalArgumentException in case the {@code objectToSave} is collection-like.
 	 */
 	<T> T insert(T objectToSave, String collectionName);
 
@@ -1324,12 +1319,9 @@ public interface MongoOperations extends FluentMongoOperations {
 	 * property type will be handled by Spring's BeanWrapper class that leverages Type Conversion API. See
 	 * <a href="https://docs.spring.io/spring/docs/current/spring-framework-reference/core.html#validation" > Spring's
 	 * Type Conversion"</a> for more details.
-	 * <p />
-	 * The {@code objectToSave} must not be collection-like.
 	 *
 	 * @param objectToSave the object to store in the collection. Must not be {@literal null}.
 	 * @return the saved object.
-	 * @throws IllegalArgumentException in case the {@code objectToSave} is collection-like.
 	 */
 	<T> T save(T objectToSave);
 
@@ -1345,13 +1337,10 @@ public interface MongoOperations extends FluentMongoOperations {
 	 * property type will be handled by Spring's BeanWrapper class that leverages Type Conversion API. See <a
 	 * https://docs.spring.io/spring/docs/current/spring-framework-reference/core.html#validation">Spring's Type
 	 * Conversion"</a> for more details.
-	 * <p />
-	 * The {@code objectToSave} must not be collection-like.
 	 *
 	 * @param objectToSave the object to store in the collection. Must not be {@literal null}.
 	 * @param collectionName name of the collection to store the object in. Must not be {@literal null}.
 	 * @return the saved object.
-	 * @throws IllegalArgumentException in case the {@code objectToSave} is collection-like.
 	 */
 	<T> T save(T objectToSave, String collectionName);
 

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/MongoTemplate.java

@@ -28,7 +28,6 @@ import org.bson.Document;
 import org.bson.conversions.Bson;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
-
 import org.springframework.beans.BeansException;
 import org.springframework.context.ApplicationContext;
 import org.springframework.context.ApplicationContextAware;
@@ -47,7 +46,6 @@ import org.springframework.data.geo.Distance;
 import org.springframework.data.geo.GeoResult;
 import org.springframework.data.geo.GeoResults;
 import org.springframework.data.geo.Metric;
-import org.springframework.data.mapping.MappingException;
 import org.springframework.data.mapping.callback.EntityCallbacks;
 import org.springframework.data.mapping.context.MappingContext;
 import org.springframework.data.mongodb.MongoDatabaseFactory;
@@ -56,7 +54,6 @@ import org.springframework.data.mongodb.SessionSynchronization;
 import org.springframework.data.mongodb.core.BulkOperations.BulkMode;
 import org.springframework.data.mongodb.core.DefaultBulkOperations.BulkOperationContext;
 import org.springframework.data.mongodb.core.EntityOperations.AdaptibleEntity;
-import org.springframework.data.mongodb.core.QueryOperations.AggregationDefinition;
 import org.springframework.data.mongodb.core.QueryOperations.CountContext;
 import org.springframework.data.mongodb.core.QueryOperations.DeleteContext;
 import org.springframework.data.mongodb.core.QueryOperations.DistinctQueryContext;
@@ -99,12 +96,12 @@ import org.springframework.data.mongodb.core.query.NearQuery;
 import org.springframework.data.mongodb.core.query.Query;
 import org.springframework.data.mongodb.core.query.UpdateDefinition;
 import org.springframework.data.mongodb.core.query.UpdateDefinition.ArrayFilter;
-import org.springframework.data.mongodb.core.timeseries.Granularity;
 import org.springframework.data.mongodb.core.validation.Validator;
 import org.springframework.data.mongodb.util.BsonUtils;
 import org.springframework.data.projection.SpelAwareProxyProjectionFactory;
 import org.springframework.data.util.CloseableIterator;
 import org.springframework.data.util.Optionals;
+import org.springframework.jca.cci.core.ConnectionCallback;
 import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 import org.springframework.util.ClassUtils;
@@ -158,13 +155,22 @@ import com.mongodb.client.result.UpdateResult;
  * @author Michael J. Simons
  * @author Roman Puchkovskiy
  * @author Yadhukrishna S Pai
- * @author Anton Barkan
- * @author Bartłomiej Mazur
  */
 public class MongoTemplate implements MongoOperations, ApplicationContextAware, IndexOperationsProvider {
 
 	private static final Logger LOGGER = LoggerFactory.getLogger(MongoTemplate.class);
 	private static final WriteResultChecking DEFAULT_WRITE_RESULT_CHECKING = WriteResultChecking.NONE;
+	private static final Collection<String> ITERABLE_CLASSES;
+
+	static {
+
+		Set<String> iterableClasses = new HashSet<>();
+		iterableClasses.add(List.class.getName());
+		iterableClasses.add(Collection.class.getName());
+		iterableClasses.add(Iterator.class.getName());
+
+		ITERABLE_CLASSES = Collections.unmodifiableCollection(iterableClasses);
+	}
 
 	private final MongoConverter mongoConverter;
 	private final MappingContext<? extends MongoPersistentEntity<?>, MongoPersistentProperty> mappingContext;
@@ -598,7 +604,7 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 	 * @see org.springframework.data.mongodb.core.MongoOperations#createCollection(java.lang.Class)
 	 */
 	public <T> MongoCollection<Document> createCollection(Class<T> entityClass) {
-		return createCollection(entityClass, operations.forType(entityClass).getCollectionOptions());
+		return createCollection(entityClass, CollectionOptions.empty());
 	}
 
 	/*
@@ -707,17 +713,12 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 		});
 	}
 
-	@Override
-	public IndexOperations indexOps(String collectionName) {
-		return indexOps(collectionName, null);
-	}
-
 	/*
 	 * (non-Javadoc)
 	 * @see org.springframework.data.mongodb.core.ExecutableInsertOperation#indexOps(java.lang.String)
 	 */
-	public IndexOperations indexOps(String collectionName, @Nullable Class<?> type) {
-		return new DefaultIndexOperations(this, collectionName, type);
+	public IndexOperations indexOps(String collectionName) {
+		return new DefaultIndexOperations(this, collectionName, null);
 	}
 
 	/*
@@ -725,7 +726,7 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 	 * @see org.springframework.data.mongodb.core.ExecutableInsertOperation#indexOps(java.lang.Class)
 	 */
 	public IndexOperations indexOps(Class<?> entityClass) {
-		return indexOps(getCollectionName(entityClass), entityClass);
+		return new DefaultIndexOperations(this, getCollectionName(entityClass), entityClass);
 	}
 
 	/*
@@ -974,7 +975,7 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 		for (Document element : results) {
 
 			GeoResult<T> geoResult = callback.doWith(element);
-			aggregate = aggregate.add(BigDecimal.valueOf(geoResult.getDistance().getValue()));
+			aggregate = aggregate.add(new BigDecimal(geoResult.getDistance().getValue()));
 			result.add(geoResult);
 		}
 
@@ -1174,28 +1175,11 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 		return (T) doInsert(collectionName, objectToSave, this.mongoConverter);
 	}
 
-	/**
-	 * Ensure the given {@literal source} is not an {@link java.lang.reflect.Array}, {@link Collection} or
-	 * {@link Iterator}.
-	 *
-	 * @param source can be {@literal null}.
-	 * @deprecated since 3.2. Call {@link #ensureNotCollectionLike(Object)} instead.
-	 */
-	protected void ensureNotIterable(@Nullable Object source) {
-		ensureNotCollectionLike(source);
-	}
-
-	/**
-	 * Ensure the given {@literal source} is not an {@link java.lang.reflect.Array}, {@link Collection} or
-	 * {@link Iterator}.
-	 *
-	 * @param source can be {@literal null}.
-	 * @since 3.2.
-	 */
-	protected void ensureNotCollectionLike(@Nullable Object source) {
-
-		if (EntityOperations.isCollectionLike(source)) {
-			throw new IllegalArgumentException("Cannot use a collection here.");
+	protected void ensureNotIterable(@Nullable Object o) {
+		if (o != null) {
+			if (o.getClass().isArray() || ITERABLE_CLASSES.contains(o.getClass().getName())) {
+				throw new IllegalArgumentException("Cannot use a collection here.");
+			}
 		}
 	}
 
@@ -1378,7 +1362,6 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 
 		Assert.notNull(objectToSave, "Object to save must not be null!");
 		Assert.hasText(collectionName, "Collection name must not be null or empty!");
-		ensureNotCollectionLike(objectToSave);
 
 		AdaptibleEntity<T> source = operations.forEntity(objectToSave, mongoConverter.getConversionService());
 
@@ -2003,7 +1986,7 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 	public <O> AggregationResults<O> aggregate(Aggregation aggregation, Class<?> inputType, Class<O> outputType) {
 
 		return aggregate(aggregation, getCollectionName(inputType), outputType,
-				queryOperations.createAggregation(aggregation, inputType).getAggregationOperationContext());
+				new TypeBasedAggregationOperationContext(inputType, mappingContext, queryMapper));
 	}
 
 	/* (non-Javadoc)
@@ -2110,13 +2093,9 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 		Assert.notNull(aggregation, "Aggregation pipeline must not be null!");
 		Assert.notNull(outputType, "Output type must not be null!");
 
-		return doAggregate(aggregation, collectionName, outputType,
-				queryOperations.createAggregation(aggregation, context));
-	}
-
-	private <O> AggregationResults<O> doAggregate(Aggregation aggregation, String collectionName, Class<O> outputType,
-			AggregationDefinition context) {
-		return doAggregate(aggregation, collectionName, outputType, context.getAggregationOperationContext());
+		AggregationOperationContext contextToUse = new AggregationUtil(queryMapper, mappingContext)
+				.prepareAggregationContext(aggregation, context);
+		return doAggregate(aggregation, collectionName, outputType, contextToUse);
 	}
 
 	@SuppressWarnings("ConstantConditions")
@@ -2204,10 +2183,11 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 		Assert.notNull(outputType, "Output type must not be null!");
 		Assert.isTrue(!aggregation.getOptions().isExplain(), "Can't use explain option with streaming!");
 
-		AggregationDefinition aggregationDefinition = queryOperations.createAggregation(aggregation, context);
+		AggregationUtil aggregationUtil = new AggregationUtil(queryMapper, mappingContext);
+		AggregationOperationContext rootContext = aggregationUtil.prepareAggregationContext(aggregation, context);
 
 		AggregationOptions options = aggregation.getOptions();
-		List<Document> pipeline = aggregationDefinition.getAggregationPipeline();
+		List<Document> pipeline = aggregationUtil.createPipeline(aggregation, rootContext);
 
 		if (LOGGER.isDebugEnabled()) {
 			LOGGER.debug("Streaming aggregation: {} in collection {}", serializeToJsonSafely(pipeline), collectionName);
@@ -2436,20 +2416,6 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 				co.validationOptions(options);
 			}
 
-			if (collectionOptions.containsKey("timeseries")) {
-
-				Document timeSeries = collectionOptions.get("timeseries", Document.class);
-				com.mongodb.client.model.TimeSeriesOptions options = new com.mongodb.client.model.TimeSeriesOptions(
-						timeSeries.getString("timeField"));
-				if (timeSeries.containsKey("metaField")) {
-					options.metaField(timeSeries.getString("metaField"));
-				}
-				if (timeSeries.containsKey("granularity")) {
-					options.granularity(TimeSeriesGranularity.valueOf(timeSeries.getString("granularity").toUpperCase()));
-				}
-				co.timeSeriesOptions(options);
-			}
-
 			db.createCollection(collectionName, co);
 
 			MongoCollection<Document> coll = db.getCollection(collectionName, Document.class);
@@ -2604,19 +2570,6 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 
 			collectionOptions.getValidationOptions().ifPresent(it -> it.getValidator() //
 					.ifPresent(val -> doc.put("validator", getMappedValidator(val, targetType))));
-
-			collectionOptions.getTimeSeriesOptions().map(operations.forType(targetType)::mapTimeSeriesOptions)
-					.ifPresent(it -> {
-
-						Document timeseries = new Document("timeField", it.getTimeField());
-						if (StringUtils.hasText(it.getMetaField())) {
-							timeseries.append("metaField", it.getMetaField());
-						}
-						if (!Granularity.DEFAULT.equals(it.getGranularity())) {
-							timeseries.append("granularity", it.getGranularity().name().toLowerCase());
-						}
-						doc.put("timeseries", timeseries);
-					});
 		}
 
 		return doc;
@@ -2780,24 +2733,25 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 	 * Internal method using callbacks to do queries against the datastore that requires reading a single object from a
 	 * collection of objects. It will take the following steps
 	 * <ol>
-	 * <li>Execute the given {@link CollectionCallback} for a {@link Document}.</li>
+	 * <li>Execute the given {@link ConnectionCallback} for a {@link Document}.</li>
 	 * <li>Apply the given {@link DocumentCallback} to each of the {@link Document}s to obtain the result.</li>
 	 * <ol>
 	 *
 	 * @param <T>
 	 * @param collectionCallback the callback to retrieve the {@link Document} with
-	 * @param documentCallback the {@link DocumentCallback} to transform {@link Document}s into the actual domain type
+	 * @param objectCallback the {@link DocumentCallback} to transform {@link Document}s into the actual domain type
 	 * @param collectionName the collection to be queried
 	 * @return
 	 */
 	@Nullable
 	private <T> T executeFindOneInternal(CollectionCallback<Document> collectionCallback,
-			DocumentCallback<T> documentCallback, String collectionName) {
+			DocumentCallback<T> objectCallback, String collectionName) {
 
 		try {
 
-			Document document = collectionCallback.doInCollection(getAndPrepareCollection(doGetDatabase(), collectionName));
-			return document != null ? documentCallback.doWith(document) : null;
+			T result = objectCallback
+					.doWith(collectionCallback.doInCollection(getAndPrepareCollection(doGetDatabase(), collectionName)));
+			return result;
 		} catch (RuntimeException e) {
 			throw potentiallyConvertRuntimeException(e, exceptionTranslator);
 		}
@@ -2807,7 +2761,7 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 	 * Internal method using callback to do queries against the datastore that requires reading a collection of objects.
 	 * It will take the following steps
 	 * <ol>
-	 * <li>Execute the given {@link CollectionCallback} for a {@link FindIterable}.</li>
+	 * <li>Execute the given {@link ConnectionCallback} for a {@link FindIterable}.</li>
 	 * <li>Prepare that {@link FindIterable} with the given {@link CursorPreparer} (will be skipped if
 	 * {@link CursorPreparer} is {@literal null}</li>
 	 * <li>Iterate over the {@link FindIterable} and applies the given {@link DocumentCallback} to each of the
@@ -2817,27 +2771,36 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 	 * @param <T>
 	 * @param collectionCallback the callback to retrieve the {@link FindIterable} with
 	 * @param preparer the {@link CursorPreparer} to potentially modify the {@link FindIterable} before iterating over it
-	 * @param documentCallback the {@link DocumentCallback} to transform {@link Document}s into the actual domain type
+	 * @param objectCallback the {@link DocumentCallback} to transform {@link Document}s into the actual domain type
 	 * @param collectionName the collection to be queried
 	 * @return
 	 */
 	private <T> List<T> executeFindMultiInternal(CollectionCallback<FindIterable<Document>> collectionCallback,
-			CursorPreparer preparer, DocumentCallback<T> documentCallback, String collectionName) {
+			CursorPreparer preparer, DocumentCallback<T> objectCallback, String collectionName) {
 
 		try {
 
-			try (MongoCursor<Document> cursor = preparer
-					.initiateFind(getAndPrepareCollection(doGetDatabase(), collectionName), collectionCallback::doInCollection)
-					.iterator()) {
+			MongoCursor<Document> cursor = null;
+
+			try {
+
+				cursor = preparer
+						.initiateFind(getAndPrepareCollection(doGetDatabase(), collectionName), collectionCallback::doInCollection)
+						.iterator();
 
 				List<T> result = new ArrayList<>();
 
 				while (cursor.hasNext()) {
 					Document object = cursor.next();
-					result.add(documentCallback.doWith(object));
+					result.add(objectCallback.doWith(object));
 				}
 
 				return result;
+			} finally {
+
+				if (cursor != null) {
+					cursor.close();
+				}
 			}
 		} catch (RuntimeException e) {
 			throw potentiallyConvertRuntimeException(e, exceptionTranslator);
@@ -2847,12 +2810,23 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 	private void executeQueryInternal(CollectionCallback<FindIterable<Document>> collectionCallback,
 			CursorPreparer preparer, DocumentCallbackHandler callbackHandler, String collectionName) {
 
-		try (MongoCursor<Document> cursor = preparer
-				.initiateFind(getAndPrepareCollection(doGetDatabase(), collectionName), collectionCallback::doInCollection)
-				.iterator()) {
+		try {
 
-			while (cursor.hasNext()) {
-				callbackHandler.processDocument(cursor.next());
+			MongoCursor<Document> cursor = null;
+
+			try {
+
+				cursor = preparer
+						.initiateFind(getAndPrepareCollection(doGetDatabase(), collectionName), collectionCallback::doInCollection)
+						.iterator();
+
+				while (cursor.hasNext()) {
+					callbackHandler.processDocument(cursor.next());
+				}
+			} finally {
+				if (cursor != null) {
+					cursor.close();
+				}
 			}
 		} catch (RuntimeException e) {
 			throw potentiallyConvertRuntimeException(e, exceptionTranslator);
@@ -3151,7 +3125,8 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 
 	interface DocumentCallback<T> {
 
-		T doWith(Document object);
+		@Nullable
+		T doWith(@Nullable Document object);
 	}
 
 	/**
@@ -3175,19 +3150,22 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 			this.collectionName = collectionName;
 		}
 
-		public T doWith(Document document) {
+		@Nullable
+		public T doWith(@Nullable Document document) {
 
-			maybeEmitEvent(new AfterLoadEvent<>(document, type, collectionName));
-			T entity = reader.read(type, document);
+			T source = null;
 
-			if (entity == null) {
-				throw new MappingException(String.format("EntityReader %s returned null", reader));
+			if (document != null) {
+				maybeEmitEvent(new AfterLoadEvent<>(document, type, collectionName));
+				source = reader.read(type, document);
 			}
 
-			maybeEmitEvent(new AfterConvertEvent<>(document, entity, collectionName));
-			entity = maybeCallAfterConvert(entity, document, collectionName);
+			if (source != null) {
+				maybeEmitEvent(new AfterConvertEvent<>(document, source, collectionName));
+				source = maybeCallAfterConvert(source, document, collectionName);
+			}
 
-			return entity;
+			return source;
 		}
 	}
 
@@ -3220,7 +3198,8 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 		 * @see org.springframework.data.mongodb.core.MongoTemplate.DocumentCallback#doWith(org.bson.Document)
 		 */
 		@SuppressWarnings("unchecked")
-		public T doWith(Document document) {
+		@Nullable
+		public T doWith(@Nullable Document document) {
 
 			if (document == null) {
 				return null;
@@ -3231,16 +3210,15 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 
 			maybeEmitEvent(new AfterLoadEvent<>(document, targetType, collectionName));
 
-			Object entity = reader.read(typeToRead, document);
+			Object source = reader.read(typeToRead, document);
+			Object result = targetType.isInterface() ? projectionFactory.createProjection(targetType, source) : source;
 
-			if (entity == null) {
-				throw new MappingException(String.format("EntityReader %s returned null", reader));
+			if (result != null) {
+				maybeEmitEvent(new AfterConvertEvent<>(document, result, collectionName));
+				result = maybeCallAfterConvert(result, document, collectionName);
 			}
 
-			Object result = targetType.isInterface() ? projectionFactory.createProjection(targetType, entity) : entity;
-
-			maybeEmitEvent(new AfterConvertEvent<>(document, result, collectionName));
-			return (T) maybeCallAfterConvert(result, document, collectionName);
+			return (T) result;
 		}
 	}
 
@@ -3310,10 +3288,6 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 						cursorToUse = cursorToUse.batchSize(meta.getCursorBatchSize());
 					}
 
-					if (meta.getAllowDiskUse() != null) {
-						cursorToUse = cursorToUse.allowDiskUse(meta.getAllowDiskUse());
-					}
-
 					for (Meta.CursorOption option : meta.getFlags()) {
 
 						switch (option) {
@@ -3377,7 +3351,8 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 			this.metric = metric;
 		}
 
-		public GeoResult<T> doWith(Document object) {
+		@Nullable
+		public GeoResult<T> doWith(@Nullable Document object) {
 
 			double distance = Double.NaN;
 			if (object.containsKey(distanceField)) {
@@ -3404,6 +3379,10 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 
 		/**
 		 * Creates a new {@link CloseableIterableCursorAdapter} backed by the given {@link MongoCollection}.
+		 *
+		 * @param cursor
+		 * @param exceptionTranslator
+		 * @param objectReadCallback
 		 */
 		CloseableIterableCursorAdapter(MongoIterable<Document> cursor, PersistenceExceptionTranslator exceptionTranslator,
 				DocumentCallback<T> objectReadCallback) {
@@ -3447,7 +3426,8 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 
 			try {
 				Document item = cursor.next();
-				return objectReadCallback.doWith(item);
+				T converted = objectReadCallback.doWith(item);
+				return converted;
 			} catch (RuntimeException ex) {
 				throw potentiallyConvertRuntimeException(ex, exceptionTranslator);
 			}

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/QueryOperations.java

@@ -17,7 +17,6 @@ package org.springframework.data.mongodb.core;
 
 import java.util.List;
 import java.util.Map;
-import java.util.Map.Entry;
 import java.util.Optional;
 import java.util.Set;
 import java.util.concurrent.ConcurrentHashMap;
@@ -32,17 +31,11 @@ import org.springframework.data.mapping.PropertyPath;
 import org.springframework.data.mapping.PropertyReferenceException;
 import org.springframework.data.mapping.context.MappingContext;
 import org.springframework.data.mongodb.CodecRegistryProvider;
-import org.springframework.data.mongodb.MongoExpression;
 import org.springframework.data.mongodb.core.MappedDocument.MappedUpdate;
 import org.springframework.data.mongodb.core.aggregation.Aggregation;
-import org.springframework.data.mongodb.core.aggregation.AggregationExpression;
 import org.springframework.data.mongodb.core.aggregation.AggregationOperationContext;
-import org.springframework.data.mongodb.core.aggregation.AggregationOptions;
-import org.springframework.data.mongodb.core.aggregation.AggregationPipeline;
 import org.springframework.data.mongodb.core.aggregation.AggregationUpdate;
 import org.springframework.data.mongodb.core.aggregation.RelaxedTypeBasedAggregationOperationContext;
-import org.springframework.data.mongodb.core.aggregation.TypeBasedAggregationOperationContext;
-import org.springframework.data.mongodb.core.aggregation.TypedAggregation;
 import org.springframework.data.mongodb.core.convert.QueryMapper;
 import org.springframework.data.mongodb.core.convert.UpdateMapper;
 import org.springframework.data.mongodb.core.mapping.MongoPersistentEntity;
@@ -55,7 +48,6 @@ import org.springframework.data.mongodb.core.query.UpdateDefinition;
 import org.springframework.data.mongodb.core.query.UpdateDefinition.ArrayFilter;
 import org.springframework.data.mongodb.util.BsonUtils;
 import org.springframework.data.projection.ProjectionFactory;
-import org.springframework.data.util.Lazy;
 import org.springframework.lang.Nullable;
 import org.springframework.util.ClassUtils;
 import org.springframework.util.ObjectUtils;
@@ -202,34 +194,9 @@ class QueryOperations {
 		return new DeleteContext(query, false);
 	}
 
-	/**
-	 * Create a new {@link AggregationDefinition} for the given {@link Aggregation}.
-	 *
-	 * @param aggregation must not be {@literal null}.
-	 * @param inputType fallback mapping type in case of untyped aggregation. Can be {@literal null}.
-	 * @return new instance of {@link AggregationDefinition}.
-	 * @since 3.2
-	 */
-	AggregationDefinition createAggregation(Aggregation aggregation, @Nullable Class<?> inputType) {
-		return new AggregationDefinition(aggregation, inputType);
-	}
-
-	/**
-	 * Create a new {@link AggregationDefinition} for the given {@link Aggregation}.
-	 *
-	 * @param aggregation must not be {@literal null}.
-	 * @param aggregationOperationContext the {@link AggregationOperationContext} to use. Can be {@literal null}.
-	 * @return new instance of {@link AggregationDefinition}.
-	 * @since 3.2
-	 */
-	AggregationDefinition createAggregation(Aggregation aggregation,
-			@Nullable AggregationOperationContext aggregationOperationContext) {
-		return new AggregationDefinition(aggregation, aggregationOperationContext);
-	}
-
 	/**
 	 * {@link QueryContext} encapsulates common tasks required to convert a {@link Query} into its MongoDB document
-	 * representation, mapping field names, as well as determining and applying {@link Collation collations}.
+	 * representation, mapping fieldnames, as well as determinging and applying {@link Collation collations}.
 	 *
 	 * @author Christoph Strobl
 	 */
@@ -238,7 +205,7 @@ class QueryOperations {
 		private final Query query;
 
 		/**
-		 * Create new a {@link QueryContext} instance from the given {@literal query} (can be either a {@link Query} or a
+		 * Create new a {@link QueryContext} instance from the given {@literal query} (can be eihter a {@link Query} or a
 		 * plain {@link Document}.
 		 *
 		 * @param query can be {@literal null}.
@@ -291,21 +258,7 @@ class QueryOperations {
 		Document getMappedFields(@Nullable MongoPersistentEntity<?> entity, Class<?> targetType,
 				ProjectionFactory projectionFactory) {
 
-			Document fields = new Document();
-
-			for (Entry<String, Object> entry : query.getFieldsObject().entrySet()) {
-
-				if (entry.getValue() instanceof MongoExpression) {
-
-					AggregationOperationContext ctx = entity == null ? Aggregation.DEFAULT_CONTEXT
-							: new RelaxedTypeBasedAggregationOperationContext(entity.getType(), mappingContext, queryMapper);
-
-					fields.put(entry.getKey(), AggregationExpression.from((MongoExpression) entry.getValue()).toDocument(ctx));
-				} else {
-					fields.put(entry.getKey(), entry.getValue());
-				}
-			}
-
+			Document fields = query.getFieldsObject();
 			Document mappedFields = fields;
 
 			if (entity == null) {
@@ -322,7 +275,7 @@ class QueryOperations {
 						mappingContext.getRequiredPersistentEntity(targetType));
 			}
 
-			if (entity.hasTextScoreProperty() && !query.getQueryObject().containsKey("$text")) {
+			if (entity != null && entity.hasTextScoreProperty() && !query.getQueryObject().containsKey("$text")) {
 				mappedFields.remove(entity.getTextScoreProperty().getFieldName());
 			}
 
@@ -388,8 +341,7 @@ class QueryOperations {
 		}
 
 		@Override
-		Document getMappedFields(@Nullable MongoPersistentEntity<?> entity, Class<?> targetType,
-				ProjectionFactory projectionFactory) {
+		Document getMappedFields(@Nullable MongoPersistentEntity<?> entity, Class<?> targetType, ProjectionFactory projectionFactory) {
 			return getMappedFields(entity);
 		}
 
@@ -758,8 +710,7 @@ class QueryOperations {
 
 			Class<?> type = domainType != null ? domainType : Object.class;
 
-			AggregationOperationContext context = new RelaxedTypeBasedAggregationOperationContext(type, mappingContext,
-					queryMapper);
+			AggregationOperationContext context = new RelaxedTypeBasedAggregationOperationContext(type, mappingContext, queryMapper);
 			return aggregationUtil.createPipeline((AggregationUpdate) update, context);
 		}
 
@@ -809,105 +760,4 @@ class QueryOperations {
 			return multi;
 		}
 	}
-
-	/**
-	 * A value object that encapsulates common tasks required when running {@literal aggregations}.
-	 *
-	 * @since 3.2
-	 */
-	class AggregationDefinition {
-
-		private final Aggregation aggregation;
-		private final Lazy<AggregationOperationContext> aggregationOperationContext;
-		private final Lazy<List<Document>> pipeline;
-		private final @Nullable Class<?> inputType;
-
-		/**
-		 * Creates new instance of {@link AggregationDefinition} extracting the input type from either the
-		 * {@link org.springframework.data.mongodb.core.aggregation.Aggregation} in case of a {@link TypedAggregation} or
-		 * the given {@literal aggregationOperationContext} if present. <br />
-		 * Creates a new {@link AggregationOperationContext} if none given, based on the {@link Aggregation} input type and
-		 * the desired {@link AggregationOptions#getDomainTypeMapping() domain type mapping}. <br />
-		 * Pipelines are mapped on first access of {@link #getAggregationPipeline()} and cached for reuse.
-		 *
-		 * @param aggregation the source aggregation.
-		 * @param aggregationOperationContext can be {@literal null}.
-		 */
-		AggregationDefinition(Aggregation aggregation, @Nullable AggregationOperationContext aggregationOperationContext) {
-
-			this.aggregation = aggregation;
-
-			if (aggregation instanceof TypedAggregation) {
-				this.inputType = ((TypedAggregation<?>) aggregation).getInputType();
-			} else if (aggregationOperationContext instanceof TypeBasedAggregationOperationContext) {
-				this.inputType = ((TypeBasedAggregationOperationContext) aggregationOperationContext).getType();
-			} else {
-				this.inputType = null;
-			}
-
-			this.aggregationOperationContext = Lazy.of(() -> aggregationOperationContext != null ? aggregationOperationContext
-					: aggregationUtil.createAggregationContext(aggregation, getInputType()));
-			this.pipeline = Lazy.of(() -> aggregationUtil.createPipeline(this.aggregation, getAggregationOperationContext()));
-		}
-
-		/**
-		 * Creates new instance of {@link AggregationDefinition} extracting the input type from either the
-		 * {@link org.springframework.data.mongodb.core.aggregation.Aggregation} in case of a {@link TypedAggregation} or
-		 * the given {@literal aggregationOperationContext} if present. <br />
-		 * Creates a new {@link AggregationOperationContext} based on the {@link Aggregation} input type and the desired
-		 * {@link AggregationOptions#getDomainTypeMapping() domain type mapping}. <br />
-		 * Pipelines are mapped on first access of {@link #getAggregationPipeline()} and cached for reuse.
-		 *
-		 * @param aggregation the source aggregation.
-		 * @param inputType can be {@literal null}.
-		 */
-		AggregationDefinition(Aggregation aggregation, @Nullable Class<?> inputType) {
-
-			this.aggregation = aggregation;
-
-			if (aggregation instanceof TypedAggregation) {
-				this.inputType = ((TypedAggregation<?>) aggregation).getInputType();
-			} else {
-				this.inputType = inputType;
-			}
-
-			this.aggregationOperationContext = Lazy
-					.of(() -> aggregationUtil.createAggregationContext(aggregation, getInputType()));
-			this.pipeline = Lazy.of(() -> aggregationUtil.createPipeline(this.aggregation, getAggregationOperationContext()));
-		}
-
-		/**
-		 * Obtain the already mapped pipeline.
-		 *
-		 * @return never {@literal null}.
-		 */
-		List<Document> getAggregationPipeline() {
-			return pipeline.get();
-		}
-
-		/**
-		 * @return {@literal true} if the last aggregation stage is either {@literal $out} or {@literal $merge}.
-		 * @see AggregationPipeline#isOutOrMerge()
-		 */
-		boolean isOutOrMerge() {
-			return aggregation.getPipeline().isOutOrMerge();
-		}
-
-		/**
-		 * Obtain the {@link AggregationOperationContext} used for mapping the pipeline.
-		 *
-		 * @return never {@literal null}.
-		 */
-		AggregationOperationContext getAggregationOperationContext() {
-			return aggregationOperationContext.get();
-		}
-
-		/**
-		 * @return the input type to map the pipeline against. Can be {@literal null}.
-		 */
-		@Nullable
-		Class<?> getInputType() {
-			return inputType;
-		}
-	}
 }

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/ReactiveMongoOperations.java

@@ -1038,13 +1038,11 @@ public interface ReactiveMongoOperations extends ReactiveFluentMongoOperations {
 	 * <a href="https://docs.spring.io/spring/docs/current/spring-framework-reference/core.html#validation" > Spring's
 	 * Type Conversion"</a> for more details.
 	 * <p/>
+	 * <p/>
 	 * Insert is used to initially store the object into the database. To update an existing object use the save method.
-	 * <p />
-	 * The {@code objectToSave} must not be collection-like.
 	 *
 	 * @param objectToSave the object to store in the collection. Must not be {@literal null}.
 	 * @return the inserted object.
-	 * @throws IllegalArgumentException in case the {@code objectToSave} is collection-like.
 	 */
 	<T> Mono<T> insert(T objectToSave);
 
@@ -1055,13 +1053,10 @@ public interface ReactiveMongoOperations extends ReactiveFluentMongoOperations {
 	 * configured otherwise, an instance of {@link MappingMongoConverter} will be used.
 	 * <p/>
 	 * Insert is used to initially store the object into the database. To update an existing object use the save method.
-	 * <p />
-	 * The {@code objectToSave} must not be collection-like.
 	 *
 	 * @param objectToSave the object to store in the collection. Must not be {@literal null}.
 	 * @param collectionName name of the collection to store the object in. Must not be {@literal null}.
 	 * @return the inserted object.
-	 * @throws IllegalArgumentException in case the {@code objectToSave} is collection-like.
 	 */
 	<T> Mono<T> insert(T objectToSave, String collectionName);
 
@@ -1103,6 +1098,7 @@ public interface ReactiveMongoOperations extends ReactiveFluentMongoOperations {
 	 * <a href="https://docs.spring.io/spring/docs/current/spring-framework-reference/core.html#validation" > Spring's
 	 * Type Conversion"</a> for more details.
 	 * <p/>
+	 * <p/>
 	 * Insert is used to initially store the object into the database. To update an existing object use the save method.
 	 *
 	 * @param objectToSave the object to store in the collection. Must not be {@literal null}.
@@ -1149,12 +1145,9 @@ public interface ReactiveMongoOperations extends ReactiveFluentMongoOperations {
 	 * property type will be handled by Spring's BeanWrapper class that leverages Type Conversion API. See
 	 * <a href="https://docs.spring.io/spring/docs/current/spring-framework-reference/core.html#validation" > Spring's
 	 * Type Conversion"</a> for more details.
-	 * <p />
-	 * The {@code objectToSave} must not be collection-like.
 	 *
 	 * @param objectToSave the object to store in the collection. Must not be {@literal null}.
 	 * @return the saved object.
-	 * @throws IllegalArgumentException in case the {@code objectToSave} is collection-like.
 	 */
 	<T> Mono<T> save(T objectToSave);
 
@@ -1174,7 +1167,6 @@ public interface ReactiveMongoOperations extends ReactiveFluentMongoOperations {
 	 * @param objectToSave the object to store in the collection. Must not be {@literal null}.
 	 * @param collectionName name of the collection to store the object in. Must not be {@literal null}.
 	 * @return the saved object.
-	 * @throws IllegalArgumentException in case the {@code objectToSave} is collection-like.
 	 */
 	<T> Mono<T> save(T objectToSave, String collectionName);
 

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/ReactiveMongoTemplate.java

@@ -17,20 +17,13 @@ package org.springframework.data.mongodb.core;
 
 import static org.springframework.data.mongodb.core.query.SerializationUtils.*;
 
+import org.springframework.data.mongodb.core.aggregation.RelaxedTypeBasedAggregationOperationContext;
 import reactor.core.publisher.Flux;
 import reactor.core.publisher.Mono;
 import reactor.util.function.Tuple2;
 import reactor.util.function.Tuples;
 
-import java.util.ArrayList;
-import java.util.Arrays;
-import java.util.Collection;
-import java.util.Collections;
-import java.util.HashMap;
-import java.util.Iterator;
-import java.util.List;
-import java.util.Map;
-import java.util.Optional;
+import java.util.*;
 import java.util.concurrent.TimeUnit;
 import java.util.function.Consumer;
 import java.util.function.Function;
@@ -60,7 +53,6 @@ import org.springframework.data.convert.EntityReader;
 import org.springframework.data.geo.Distance;
 import org.springframework.data.geo.GeoResult;
 import org.springframework.data.geo.Metric;
-import org.springframework.data.mapping.MappingException;
 import org.springframework.data.mapping.PersistentEntity;
 import org.springframework.data.mapping.callback.ReactiveEntityCallbacks;
 import org.springframework.data.mapping.context.MappingContext;
@@ -70,7 +62,6 @@ import org.springframework.data.mongodb.ReactiveMongoDatabaseFactory;
 import org.springframework.data.mongodb.ReactiveMongoDatabaseUtils;
 import org.springframework.data.mongodb.SessionSynchronization;
 import org.springframework.data.mongodb.core.EntityOperations.AdaptibleEntity;
-import org.springframework.data.mongodb.core.QueryOperations.AggregationDefinition;
 import org.springframework.data.mongodb.core.QueryOperations.CountContext;
 import org.springframework.data.mongodb.core.QueryOperations.DeleteContext;
 import org.springframework.data.mongodb.core.QueryOperations.DistinctQueryContext;
@@ -80,7 +71,6 @@ import org.springframework.data.mongodb.core.aggregation.Aggregation;
 import org.springframework.data.mongodb.core.aggregation.AggregationOperationContext;
 import org.springframework.data.mongodb.core.aggregation.AggregationOptions;
 import org.springframework.data.mongodb.core.aggregation.PrefixingDelegatingAggregationOperationContext;
-import org.springframework.data.mongodb.core.aggregation.RelaxedTypeBasedAggregationOperationContext;
 import org.springframework.data.mongodb.core.aggregation.TypeBasedAggregationOperationContext;
 import org.springframework.data.mongodb.core.aggregation.TypedAggregation;
 import org.springframework.data.mongodb.core.convert.DbRefResolver;
@@ -110,7 +100,6 @@ import org.springframework.data.mongodb.core.query.NearQuery;
 import org.springframework.data.mongodb.core.query.Query;
 import org.springframework.data.mongodb.core.query.UpdateDefinition;
 import org.springframework.data.mongodb.core.query.UpdateDefinition.ArrayFilter;
-import org.springframework.data.mongodb.core.timeseries.Granularity;
 import org.springframework.data.mongodb.core.validation.Validator;
 import org.springframework.data.mongodb.util.BsonUtils;
 import org.springframework.data.projection.SpelAwareProxyProjectionFactory;
@@ -167,6 +156,18 @@ public class ReactiveMongoTemplate implements ReactiveMongoOperations, Applicati
 
 	private static final Logger LOGGER = LoggerFactory.getLogger(ReactiveMongoTemplate.class);
 	private static final WriteResultChecking DEFAULT_WRITE_RESULT_CHECKING = WriteResultChecking.NONE;
+	private static final Collection<Class<?>> ITERABLE_CLASSES;
+
+	static {
+
+		Set<Class<?>> iterableClasses = new HashSet<>();
+		iterableClasses.add(List.class);
+		iterableClasses.add(Collection.class);
+		iterableClasses.add(Iterator.class);
+		iterableClasses.add(Publisher.class);
+
+		ITERABLE_CLASSES = Collections.unmodifiableCollection(iterableClasses);
+	}
 
 	private final MongoConverter mongoConverter;
 	private final MappingContext<? extends MongoPersistentEntity<?>, MongoPersistentProperty> mappingContext;
@@ -666,7 +667,7 @@ public class ReactiveMongoTemplate implements ReactiveMongoOperations, Applicati
 	 * @see org.springframework.data.mongodb.core.ReactiveMongoOperations#createCollection(java.lang.Class)
 	 */
 	public <T> Mono<MongoCollection<Document>> createCollection(Class<T> entityClass) {
-		return createCollection(entityClass, operations.forType(entityClass).getCollectionOptions());
+		return createCollection(entityClass, CollectionOptions.empty());
 	}
 
 	/*
@@ -945,7 +946,9 @@ public class ReactiveMongoTemplate implements ReactiveMongoOperations, Applicati
 
 		Assert.notNull(aggregation, "Aggregation pipeline must not be null!");
 
-		return doAggregate(aggregation, inputCollectionName, aggregation.getInputType(), outputType);
+		AggregationOperationContext context = new TypeBasedAggregationOperationContext(aggregation.getInputType(),
+				mappingContext, queryMapper);
+		return aggregate(aggregation, inputCollectionName, outputType, context);
 	}
 
 	/*
@@ -963,7 +966,9 @@ public class ReactiveMongoTemplate implements ReactiveMongoOperations, Applicati
 	 */
 	@Override
 	public <O> Flux<O> aggregate(Aggregation aggregation, Class<?> inputType, Class<O> outputType) {
-		return doAggregate(aggregation, getCollectionName(inputType), inputType, outputType);
+
+		return aggregate(aggregation, getCollectionName(inputType), outputType,
+				new TypeBasedAggregationOperationContext(inputType, mappingContext, queryMapper));
 	}
 
 	/*
@@ -972,34 +977,45 @@ public class ReactiveMongoTemplate implements ReactiveMongoOperations, Applicati
 	 */
 	@Override
 	public <O> Flux<O> aggregate(Aggregation aggregation, String collectionName, Class<O> outputType) {
-		return doAggregate(aggregation, collectionName, null, outputType);
+		return aggregate(aggregation, collectionName, outputType, null);
 	}
 
-	protected <O> Flux<O> doAggregate(Aggregation aggregation, String collectionName, @Nullable Class<?> inputType,
-			Class<O> outputType) {
+	/**
+	 * @param aggregation must not be {@literal null}.
+	 * @param collectionName must not be {@literal null}.
+	 * @param outputType must not be {@literal null}.
+	 * @param context can be {@literal null} and will be defaulted to {@link Aggregation#DEFAULT_CONTEXT}.
+	 * @return never {@literal null}.
+	 */
+	protected <O> Flux<O> aggregate(Aggregation aggregation, String collectionName, Class<O> outputType,
+			@Nullable AggregationOperationContext context) {
 
 		Assert.notNull(aggregation, "Aggregation pipeline must not be null!");
 		Assert.hasText(collectionName, "Collection name must not be null or empty!");
 		Assert.notNull(outputType, "Output type must not be null!");
 
+		AggregationUtil aggregationUtil = new AggregationUtil(queryMapper, mappingContext);
+		AggregationOperationContext rootContext = aggregationUtil.prepareAggregationContext(aggregation, context);
+
 		AggregationOptions options = aggregation.getOptions();
+		List<Document> pipeline = aggregationUtil.createPipeline(aggregation, rootContext);
+
 		Assert.isTrue(!options.isExplain(), "Cannot use explain option with streaming!");
 
-		AggregationDefinition ctx = queryOperations.createAggregation(aggregation, inputType);
-
 		if (LOGGER.isDebugEnabled()) {
-			LOGGER.debug("Streaming aggregation: {} in collection {}", serializeToJsonSafely(ctx.getAggregationPipeline()),
-					collectionName);
+			LOGGER.debug("Streaming aggregation: {} in collection {}", serializeToJsonSafely(pipeline), collectionName);
 		}
 
 		ReadDocumentCallback<O> readCallback = new ReadDocumentCallback<>(mongoConverter, outputType, collectionName);
-		return execute(collectionName, collection -> aggregateAndMap(collection, ctx.getAggregationPipeline(),
-				ctx.isOutOrMerge(), options, readCallback, ctx.getInputType()));
+		return execute(collectionName,
+				collection -> aggregateAndMap(collection, pipeline, aggregation.getPipeline().isOutOrMerge(), options,
+						readCallback,
+						aggregation instanceof TypedAggregation ? ((TypedAggregation<?>) aggregation).getInputType() : null));
 	}
 
 	private <O> Flux<O> aggregateAndMap(MongoCollection<Document> collection, List<Document> pipeline,
-			boolean isOutOrMerge, AggregationOptions options, ReadDocumentCallback<O> readCallback,
-			@Nullable Class<?> inputType) {
+			boolean isOutOrMerge,
+			AggregationOptions options, ReadDocumentCallback<O> readCallback, @Nullable Class<?> inputType) {
 
 		AggregatePublisher<Document> cursor = collection.aggregate(pipeline, Document.class)
 				.allowDiskUse(options.isAllowDiskUse());
@@ -2506,20 +2522,6 @@ public class ReactiveMongoTemplate implements ReactiveMongoOperations, Applicati
 			result.validationOptions(validationOptions);
 		});
 
-		collectionOptions.getTimeSeriesOptions().map(operations.forType(entityType)::mapTimeSeriesOptions).ifPresent(it -> {
-
-			TimeSeriesOptions options = new TimeSeriesOptions(it.getTimeField());
-
-			if (StringUtils.hasText(it.getMetaField())) {
-				options.metaField(it.getMetaField());
-			}
-			if (!Granularity.DEFAULT.equals(it.getGranularity())) {
-				options.granularity(TimeSeriesGranularity.valueOf(it.getGranularity().name().toUpperCase()));
-			}
-
-			result.timeSeriesOptions(options);
-		});
-
 		return result;
 	}
 
@@ -2680,27 +2682,13 @@ public class ReactiveMongoTemplate implements ReactiveMongoOperations, Applicati
 		}
 	}
 
-	/**
-	 * Ensure the given {@literal source} is not an {@link java.lang.reflect.Array}, {@link Collection} or
-	 * {@link Iterator}.
-	 *
-	 * @param source can be {@literal null}.
-	 * @deprecated since 3.2. Call {@link #ensureNotCollectionLike(Object)} instead.
-	 */
-	protected void ensureNotIterable(@Nullable Object source) {
-		ensureNotCollectionLike(source);
-	}
+	protected void ensureNotIterable(Object o) {
 
-	/**
-	 * Ensure the given {@literal source} is not an {@link java.lang.reflect.Array}, {@link Collection} or
-	 * {@link Iterator}.
-	 *
-	 * @param source can be {@literal null}.
-	 * @since 3.2.
-	 */
-	protected void ensureNotCollectionLike(@Nullable Object source) {
+		boolean isIterable = o.getClass().isArray()
+				|| ITERABLE_CLASSES.stream().anyMatch(iterableClass -> iterableClass.isAssignableFrom(o.getClass())
+						|| o.getClass().getName().equals(iterableClass.getName()));
 
-		if (EntityOperations.isCollectionLike(source) || source instanceof Publisher) {
+		if (isIterable) {
 			throw new IllegalArgumentException("Cannot use a collection here.");
 		}
 	}
@@ -3177,14 +3165,13 @@ public class ReactiveMongoTemplate implements ReactiveMongoOperations, Applicati
 
 			maybeEmitEvent(new AfterLoadEvent<>(document, type, collectionName));
 
-			T entity = reader.read(type, document);
-
-			if (entity == null) {
-				throw new MappingException(String.format("EntityReader %s returned null", reader));
+			T source = reader.read(type, document);
+			if (source != null) {
+				maybeEmitEvent(new AfterConvertEvent<>(document, source, collectionName));
+				return maybeCallAfterConvert(source, document, collectionName);
 			}
 
-			maybeEmitEvent(new AfterConvertEvent<>(document, entity, collectionName));
-			return maybeCallAfterConvert(entity, document, collectionName);
+			return Mono.empty();
 		}
 	}
 
@@ -3222,17 +3209,16 @@ public class ReactiveMongoTemplate implements ReactiveMongoOperations, Applicati
 
 			maybeEmitEvent(new AfterLoadEvent<>(document, typeToRead, collectionName));
 
-			Object entity = reader.read(typeToRead, document);
-
-			if (entity == null) {
-				throw new MappingException(String.format("EntityReader %s returned null", reader));
-			}
-
-			Object result = targetType.isInterface() ? projectionFactory.createProjection(targetType, entity) : entity;
+			Object source = reader.read(typeToRead, document);
+			Object result = targetType.isInterface() ? projectionFactory.createProjection(targetType, source) : source;
 
 			T castEntity = (T) result;
-			maybeEmitEvent(new AfterConvertEvent<>(document, castEntity, collectionName));
-			return maybeCallAfterConvert(castEntity, document, collectionName);
+			if (castEntity != null) {
+				maybeEmitEvent(new AfterConvertEvent<>(document, castEntity, collectionName));
+				return maybeCallAfterConvert(castEntity, document, collectionName);
+			}
+
+			return Mono.empty();
 		}
 	}
 
@@ -3351,10 +3337,6 @@ public class ReactiveMongoTemplate implements ReactiveMongoOperations, Applicati
 					if (meta.getCursorBatchSize() != null) {
 						findPublisherToUse = findPublisherToUse.batchSize(meta.getCursorBatchSize());
 					}
-
-					if (meta.getAllowDiskUse() != null) {
-						findPublisherToUse = findPublisherToUse.allowDiskUse(meta.getAllowDiskUse());
-					}
 				}
 
 			} catch (RuntimeException e) {

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/aggregation/AggregationExpression.java

@@ -16,7 +16,6 @@
 package org.springframework.data.mongodb.core.aggregation;
 
 import org.bson.Document;
-import org.springframework.data.mongodb.MongoExpression;
 
 /**
  * An {@link AggregationExpression} can be used with field expressions in aggregation pipeline stages like
@@ -26,37 +25,7 @@ import org.springframework.data.mongodb.MongoExpression;
  * @author Oliver Gierke
  * @author Christoph Strobl
  */
-public interface AggregationExpression extends MongoExpression {
-
-	/**
-	 * Create an {@link AggregationExpression} out of a given {@link MongoExpression} to ensure the resulting
-	 * {@link MongoExpression#toDocument() Document} is mapped against the {@link AggregationOperationContext}. <br />
-	 * If the given expression is already an {@link AggregationExpression} the very same instance is returned.
-	 *
-	 * @param expression must not be {@literal null}.
-	 * @return never {@literal null}.
-	 * @since 3.2
-	 */
-	static AggregationExpression from(MongoExpression expression) {
-
-		if (expression instanceof AggregationExpression) {
-			return AggregationExpression.class.cast(expression);
-		}
-
-		return (context) -> context.getMappedObject(expression.toDocument());
-	}
-
-	/**
-	 * Obtain the as is (unmapped) representation of the {@link AggregationExpression}. Use
-	 * {@link #toDocument(AggregationOperationContext)} with a matching {@link AggregationOperationContext context} to
-	 * engage domain type mapping including field name resolution.
-	 *
-	 * @see org.springframework.data.mongodb.MongoExpression#toDocument()
-	 */
-	@Override
-	default Document toDocument() {
-		return toDocument(Aggregation.DEFAULT_CONTEXT);
-	}
+public interface AggregationExpression {
 
 	/**
 	 * Turns the {@link AggregationExpression} into a {@link Document} within the given

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/aggregation/AggregationOptions.java

@@ -56,7 +56,6 @@ public class AggregationOptions {
 	private final Optional<Document> hint;
 	private Duration maxTime = Duration.ZERO;
 	private ResultOptions resultOptions = ResultOptions.READ;
-	private DomainTypeMapping domainTypeMapping = DomainTypeMapping.RELAXED;
 
 	/**
 	 * Creates a new {@link AggregationOptions}.
@@ -262,14 +261,6 @@ public class AggregationOptions {
 		return ResultOptions.SKIP.equals(resultOptions);
 	}
 
-	/**
-	 * @return the domain type mapping strategy do apply. Never {@literal null}.
-	 * @since 3.2
-	 */
-	public DomainTypeMapping getDomainTypeMapping() {
-		return domainTypeMapping;
-	}
-
 	/**
 	 * Returns a new potentially adjusted copy for the given {@code aggregationCommandObject} with the configuration
 	 * applied.
@@ -367,7 +358,6 @@ public class AggregationOptions {
 		private @Nullable Document hint;
 		private @Nullable Duration maxTime;
 		private @Nullable ResultOptions resultOptions;
-		private @Nullable DomainTypeMapping domainTypeMapping;
 
 		/**
 		 * Defines whether to off-load intensive sort-operations to disk.
@@ -485,44 +475,6 @@ public class AggregationOptions {
 			return this;
 		}
 
-		/**
-		 * Apply a strict domain type mapping considering {@link org.springframework.data.mongodb.core.mapping.Field}
-		 * annotations throwing errors for non-existent, but referenced fields.
-		 *
-		 * @return this.
-		 * @since 3.2
-		 */
-		public Builder strictMapping() {
-
-			this.domainTypeMapping = DomainTypeMapping.STRICT;
-			return this;
-		}
-
-		/**
-		 * Apply a relaxed domain type mapping considering {@link org.springframework.data.mongodb.core.mapping.Field}
-		 * annotations using the user provided name if a referenced field does not exist.
-		 *
-		 * @return this.
-		 * @since 3.2
-		 */
-		public Builder relaxedMapping() {
-
-			this.domainTypeMapping = DomainTypeMapping.RELAXED;
-			return this;
-		}
-
-		/**
-		 * Apply no domain type mapping at all taking the pipeline as-is.
-		 *
-		 * @return this.
-		 * @since 3.2
-		 */
-		public Builder noMapping() {
-
-			this.domainTypeMapping = DomainTypeMapping.NONE;
-			return this;
-		}
-
 		/**
 		 * Returns a new {@link AggregationOptions} instance with the given configuration.
 		 *
@@ -537,9 +489,6 @@ public class AggregationOptions {
 			if (resultOptions != null) {
 				options.resultOptions = resultOptions;
 			}
-			if (domainTypeMapping != null) {
-				options.domainTypeMapping = domainTypeMapping;
-			}
 
 			return options;
 		}
@@ -559,27 +508,4 @@ public class AggregationOptions {
 		 */
 		READ;
 	}
-
-	/**
-	 * Aggregation pipeline Domain type mappings supported by the mapping layer.
-	 *
-	 * @since 3.2
-	 */
-	public enum DomainTypeMapping {
-
-		/**
-		 * Mapping throws errors for non-existent, but referenced fields.
-		 */
-		STRICT,
-
-		/**
-		 * Fields that do not exist in the model are treated as-is.
-		 */
-		RELAXED,
-
-		/**
-		 * Do not attempt to map fields against the model and treat the entire pipeline as-is.
-		 */
-		NONE
-	}
 }

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/aggregation/DateOperators.java

@@ -1835,7 +1835,7 @@ public class DateOperators {
 		 * @param millisecond must not be {@literal null}.
 		 * @return new instance.
 		 * @throws IllegalArgumentException if given {@literal millisecond} is {@literal null}
-		 * @deprecated since 3.2, use {@link #millisecond(Object)} instead.
+		 * @deprecated since 3.1.3, use {@link #millisecond(Object)} instead.
 		 */
 		@Deprecated
 		default T milliseconds(Object millisecond) {
@@ -1849,7 +1849,7 @@ public class DateOperators {
 		 * @param millisecond must not be {@literal null}.
 		 * @return new instance.
 		 * @throws IllegalArgumentException if given {@literal millisecond} is {@literal null}
-		 * @since 3.2
+		 * @since 3.1.3
 		 */
 		T millisecond(Object millisecond);
 
@@ -1859,7 +1859,7 @@ public class DateOperators {
 		 * @param fieldReference must not be {@literal null}.
 		 * @return new instance.
 		 * @throws IllegalArgumentException if given {@literal fieldReference} is {@literal null}.
-		 * @deprecated since 3.2,use {@link #millisecondOf(String)} instead.
+		 * @deprecated since 3.1.3,use {@link #millisecondOf(String)} instead.
 		 */
 		@Deprecated
 		default T millisecondsOf(String fieldReference) {
@@ -1872,7 +1872,7 @@ public class DateOperators {
 		 * @param fieldReference must not be {@literal null}.
 		 * @return new instance.
 		 * @throws IllegalArgumentException if given {@literal fieldReference} is {@literal null}.
-		 * @since 3.2
+		 * @since 3.1.3
 		 */
 		default T millisecondOf(String fieldReference) {
 			return milliseconds(Fields.field(fieldReference));
@@ -1884,7 +1884,7 @@ public class DateOperators {
 		 * @param expression must not be {@literal null}.
 		 * @return new instance.
 		 * @throws IllegalArgumentException if given {@literal expression} is {@literal null}.
-		 * @deprecated since 3.2, use {@link #millisecondOf(AggregationExpression)} instead.
+		 * @deprecated since 3.1.3, use {@link #millisecondOf(AggregationExpression)} instead.
 		 */
 		@Deprecated
 		default T millisecondsOf(AggregationExpression expression) {
@@ -1897,7 +1897,7 @@ public class DateOperators {
 		 * @param expression must not be {@literal null}.
 		 * @return new instance.
 		 * @throws IllegalArgumentException if given {@literal expression} is {@literal null}.
-		 * @since 3.2
+		 * @since 3.1.3
 		 */
 		default T millisecondOf(AggregationExpression expression) {
 			return milliseconds(expression);

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/aggregation/GroupOperation.java

@@ -23,7 +23,6 @@ import java.util.List;
 import org.bson.Document;
 import org.springframework.data.mongodb.core.aggregation.ExposedFields.ExposedField;
 import org.springframework.data.mongodb.core.aggregation.ExposedFields.FieldReference;
-import org.springframework.data.mongodb.core.aggregation.ScriptOperators.Accumulator;
 import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 
@@ -376,17 +375,6 @@ public class GroupOperation implements FieldsExposingAggregationOperation {
 		return newBuilder(GroupOps.STD_DEV_POP, null, expr);
 	}
 
-	/**
-	 * Generates an {@link GroupOperationBuilder} for an {@code $accumulator}-expression.
-	 *
-	 * @param accumulator must not be {@literal null}.
-	 * @return never {@literal null}.
-	 * @since 3.2
-	 */
-	public GroupOperationBuilder accumulate(Accumulator accumulator) {
-		return new GroupOperationBuilder(this, new Operation(accumulator));
-	}
-
 	private GroupOperationBuilder newBuilder(Keyword keyword, @Nullable String reference, @Nullable Object value) {
 		return new GroupOperationBuilder(this, new Operation(keyword, null, reference, value));
 	}
@@ -477,16 +465,12 @@ public class GroupOperation implements FieldsExposingAggregationOperation {
 
 	static class Operation implements AggregationOperation {
 
-		private final @Nullable Keyword op;
+		private final Keyword op;
 		private final @Nullable String key;
 		private final @Nullable String reference;
 		private final @Nullable Object value;
 
-		Operation(AggregationExpression expression) {
-			this(null, null, null, expression);
-		}
-
-		public Operation(@Nullable Keyword op, @Nullable String key, @Nullable String reference, @Nullable Object value) {
+		public Operation(Keyword op, @Nullable String key, @Nullable String reference, @Nullable Object value) {
 
 			this.op = op;
 			this.key = key;
@@ -503,12 +487,7 @@ public class GroupOperation implements FieldsExposingAggregationOperation {
 		}
 
 		public Document toDocument(AggregationOperationContext context) {
-
-			Object value = getValue(context);
-			if(op == null && value instanceof Document) {
-				return new Document(key, value);
-			}
-			return new Document(key, new Document(op.toString(), value));
+			return new Document(key, new Document(op.toString(), getValue(context)));
 		}
 
 		public Object getValue(AggregationOperationContext context) {

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/aggregation/RelaxedTypeBasedAggregationOperationContext.java

@@ -15,7 +15,6 @@
  */
 package org.springframework.data.mongodb.core.aggregation;
 
-import org.springframework.data.mapping.MappingException;
 import org.springframework.data.mapping.context.InvalidPersistentPropertyPath;
 import org.springframework.data.mapping.context.MappingContext;
 import org.springframework.data.mongodb.core.aggregation.ExposedFields.DirectFieldReference;
@@ -56,7 +55,7 @@ public class RelaxedTypeBasedAggregationOperationContext extends TypeBasedAggreg
 
 		try {
 			return super.getReferenceFor(field);
-		} catch (MappingException e) {
+		} catch (InvalidPersistentPropertyPath e) {
 			return new DirectFieldReference(new ExposedField(field, true));
 		}
 	}

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/aggregation/TypeBasedAggregationOperationContext.java

@@ -166,8 +166,4 @@ public class TypeBasedAggregationOperationContext implements AggregationOperatio
 
 		return new DirectFieldReference(new ExposedField(mappedField, true));
 	}
-
-	public Class<?> getType() {
-		return type;
-	}
 }

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/convert/DbRefResolver.java

@@ -35,7 +35,7 @@ import com.mongodb.DBRef;
  * @author Mark Paluch
  * @since 1.4
  */
-public interface DbRefResolver extends ReferenceResolver {
+public interface DbRefResolver {
 
 	/**
 	 * Resolves the given {@link DBRef} into an object of the given {@link MongoPersistentProperty}'s type. The method

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/convert/DefaultDbRefResolver.java

@@ -15,6 +15,13 @@
  */
 package org.springframework.data.mongodb.core.convert;
 
+import static org.springframework.util.ReflectionUtils.*;
+
+import java.io.IOException;
+import java.io.ObjectInputStream;
+import java.io.ObjectOutputStream;
+import java.io.Serializable;
+import java.lang.reflect.Method;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Collections;
@@ -22,18 +29,28 @@ import java.util.List;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
 
+import org.aopalliance.intercept.MethodInterceptor;
+import org.aopalliance.intercept.MethodInvocation;
 import org.bson.Document;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
-
+import org.springframework.aop.framework.ProxyFactory;
+import org.springframework.cglib.proxy.Callback;
+import org.springframework.cglib.proxy.Enhancer;
+import org.springframework.cglib.proxy.Factory;
+import org.springframework.cglib.proxy.MethodProxy;
+import org.springframework.dao.DataAccessException;
 import org.springframework.dao.InvalidDataAccessApiUsageException;
+import org.springframework.dao.support.PersistenceExceptionTranslator;
+import org.springframework.data.mongodb.ClientSessionException;
+import org.springframework.data.mongodb.LazyLoadingException;
 import org.springframework.data.mongodb.MongoDatabaseFactory;
 import org.springframework.data.mongodb.MongoDatabaseUtils;
-import org.springframework.data.mongodb.core.convert.ReferenceLoader.DocumentReferenceQuery;
-import org.springframework.data.mongodb.core.mapping.BasicMongoPersistentProperty;
 import org.springframework.data.mongodb.core.mapping.MongoPersistentProperty;
 import org.springframework.lang.Nullable;
+import org.springframework.objenesis.ObjenesisStd;
 import org.springframework.util.Assert;
+import org.springframework.util.ReflectionUtils;
 import org.springframework.util.StringUtils;
 
 import com.mongodb.DBRef;
@@ -50,11 +67,13 @@ import com.mongodb.client.model.Filters;
  * @author Mark Paluch
  * @since 1.4
  */
-public class DefaultDbRefResolver extends DefaultReferenceResolver implements DbRefResolver, ReferenceResolver {
+public class DefaultDbRefResolver implements DbRefResolver {
 
 	private static final Logger LOGGER = LoggerFactory.getLogger(DefaultDbRefResolver.class);
 
 	private final MongoDatabaseFactory mongoDbFactory;
+	private final PersistenceExceptionTranslator exceptionTranslator;
+	private final ObjenesisStd objenesis;
 
 	/**
 	 * Creates a new {@link DefaultDbRefResolver} with the given {@link MongoDatabaseFactory}.
@@ -63,11 +82,11 @@ public class DefaultDbRefResolver extends DefaultReferenceResolver implements Db
 	 */
 	public DefaultDbRefResolver(MongoDatabaseFactory mongoDbFactory) {
 
-		super(new MongoDatabaseFactoryReferenceLoader(mongoDbFactory), mongoDbFactory.getExceptionTranslator());
-
 		Assert.notNull(mongoDbFactory, "MongoDbFactory translator must not be null!");
 
 		this.mongoDbFactory = mongoDbFactory;
+		this.exceptionTranslator = mongoDbFactory.getExceptionTranslator();
+		this.objenesis = new ObjenesisStd(true);
 	}
 
 	/*
@@ -95,8 +114,17 @@ public class DefaultDbRefResolver extends DefaultReferenceResolver implements Db
 	 */
 	@Override
 	public Document fetch(DBRef dbRef) {
-		return getReferenceLoader().fetchOne(DocumentReferenceQuery.forSingleDocument(Filters.eq("_id", dbRef.getId())),
-				ReferenceCollection.fromDBRef(dbRef));
+
+		MongoCollection<Document> mongoCollection = getCollection(dbRef);
+
+		if (LOGGER.isTraceEnabled()) {
+			LOGGER.trace("Fetching DBRef '{}' from {}.{}.", dbRef.getId(),
+					StringUtils.hasText(dbRef.getDatabaseName()) ? dbRef.getDatabaseName()
+							: mongoCollection.getNamespace().getDatabaseName(),
+					dbRef.getCollectionName());
+		}
+
+		return mongoCollection.find(Filters.eq("_id", dbRef.getId())).first();
 	}
 
 	/*
@@ -137,7 +165,7 @@ public class DefaultDbRefResolver extends DefaultReferenceResolver implements Db
 		}
 
 		List<Document> result = mongoCollection //
-				.find(new Document(BasicMongoPersistentProperty.ID_FIELD_NAME, new Document("$in", ids))) //
+				.find(new Document("_id", new Document("$in", ids))) //
 				.into(new ArrayList<>());
 
 		return ids.stream() //
@@ -157,9 +185,44 @@ public class DefaultDbRefResolver extends DefaultReferenceResolver implements Db
 	private Object createLazyLoadingProxy(MongoPersistentProperty property, @Nullable DBRef dbref,
 			DbRefResolverCallback callback, DbRefProxyHandler handler) {
 
-		Object lazyLoadingProxy = getProxyFactory().createLazyLoadingProxy(property, callback, dbref);
+		Class<?> propertyType = property.getType();
+		LazyLoadingInterceptor interceptor = new LazyLoadingInterceptor(property, dbref, exceptionTranslator, callback);
 
-		return handler.populateId(property, dbref, lazyLoadingProxy);
+		if (!propertyType.isInterface()) {
+
+			Factory factory = (Factory) objenesis.newInstance(getEnhancedTypeFor(propertyType));
+			factory.setCallbacks(new Callback[] { interceptor });
+
+			return handler.populateId(property, dbref, factory);
+		}
+
+		ProxyFactory proxyFactory = new ProxyFactory();
+
+		for (Class<?> type : propertyType.getInterfaces()) {
+			proxyFactory.addInterface(type);
+		}
+
+		proxyFactory.addInterface(LazyLoadingProxy.class);
+		proxyFactory.addInterface(propertyType);
+		proxyFactory.addAdvice(interceptor);
+
+		return handler.populateId(property, dbref, proxyFactory.getProxy(LazyLoadingProxy.class.getClassLoader()));
+	}
+
+	/**
+	 * Returns the CGLib enhanced type for the given source type.
+	 *
+	 * @param type
+	 * @return
+	 */
+	private Class<?> getEnhancedTypeFor(Class<?> type) {
+
+		Enhancer enhancer = new Enhancer();
+		enhancer.setSuperclass(type);
+		enhancer.setCallbackType(org.springframework.cglib.proxy.MethodInterceptor.class);
+		enhancer.setInterfaces(new Class[] { LazyLoadingProxy.class });
+
+		return enhancer.createClass();
 	}
 
 	/**
@@ -182,10 +245,253 @@ public class DefaultDbRefResolver extends DefaultReferenceResolver implements Db
 	private static Stream<Document> documentWithId(Object identifier, Collection<Document> documents) {
 
 		return documents.stream() //
-				.filter(it -> it.get(BasicMongoPersistentProperty.ID_FIELD_NAME).equals(identifier)) //
+				.filter(it -> it.get("_id").equals(identifier)) //
 				.limit(1);
 	}
 
+	/**
+	 * A {@link MethodInterceptor} that is used within a lazy loading proxy. The property resolving is delegated to a
+	 * {@link DbRefResolverCallback}. The resolving process is triggered by a method invocation on the proxy and is
+	 * guaranteed to be performed only once.
+	 *
+	 * @author Thomas Darimont
+	 * @author Oliver Gierke
+	 * @author Christoph Strobl
+	 */
+	static class LazyLoadingInterceptor
+			implements MethodInterceptor, org.springframework.cglib.proxy.MethodInterceptor, Serializable {
+
+		private static final Method INITIALIZE_METHOD, TO_DBREF_METHOD, FINALIZE_METHOD;
+
+		private final DbRefResolverCallback callback;
+		private final MongoPersistentProperty property;
+		private final PersistenceExceptionTranslator exceptionTranslator;
+
+		private volatile boolean resolved;
+		private final @Nullable DBRef dbref;
+		private @Nullable Object result;
+
+		static {
+			try {
+				INITIALIZE_METHOD = LazyLoadingProxy.class.getMethod("getTarget");
+				TO_DBREF_METHOD = LazyLoadingProxy.class.getMethod("toDBRef");
+				FINALIZE_METHOD = Object.class.getDeclaredMethod("finalize");
+			} catch (Exception e) {
+				throw new RuntimeException(e);
+			}
+		}
+
+		/**
+		 * Creates a new {@link LazyLoadingInterceptor} for the given {@link MongoPersistentProperty},
+		 * {@link PersistenceExceptionTranslator} and {@link DbRefResolverCallback}.
+		 *
+		 * @param property must not be {@literal null}.
+		 * @param dbref can be {@literal null}.
+		 * @param callback must not be {@literal null}.
+		 */
+		public LazyLoadingInterceptor(MongoPersistentProperty property, @Nullable DBRef dbref,
+				PersistenceExceptionTranslator exceptionTranslator, DbRefResolverCallback callback) {
+
+			Assert.notNull(property, "Property must not be null!");
+			Assert.notNull(exceptionTranslator, "Exception translator must not be null!");
+			Assert.notNull(callback, "Callback must not be null!");
+
+			this.dbref = dbref;
+			this.callback = callback;
+			this.exceptionTranslator = exceptionTranslator;
+			this.property = property;
+		}
+
+		/*
+		 * (non-Javadoc)
+		 * @see org.aopalliance.intercept.MethodInterceptor#invoke(org.aopalliance.intercept.MethodInvocation)
+		 */
+		@Override
+		public Object invoke(@Nullable MethodInvocation invocation) throws Throwable {
+			return intercept(invocation.getThis(), invocation.getMethod(), invocation.getArguments(), null);
+		}
+
+		/*
+		 * (non-Javadoc)
+		 * @see org.springframework.cglib.proxy.MethodInterceptor#intercept(java.lang.Object, java.lang.reflect.Method, java.lang.Object[], org.springframework.cglib.proxy.MethodProxy)
+		 */
+		@Nullable
+		@Override
+		public Object intercept(Object obj, Method method, Object[] args, @Nullable MethodProxy proxy) throws Throwable {
+
+			if (INITIALIZE_METHOD.equals(method)) {
+				return ensureResolved();
+			}
+
+			if (TO_DBREF_METHOD.equals(method)) {
+				return this.dbref;
+			}
+
+			if (isObjectMethod(method) && Object.class.equals(method.getDeclaringClass())) {
+
+				if (ReflectionUtils.isToStringMethod(method)) {
+					return proxyToString(proxy);
+				}
+
+				if (ReflectionUtils.isEqualsMethod(method)) {
+					return proxyEquals(proxy, args[0]);
+				}
+
+				if (ReflectionUtils.isHashCodeMethod(method)) {
+					return proxyHashCode(proxy);
+				}
+
+				// DATAMONGO-1076 - finalize methods should not trigger proxy initialization
+				if (FINALIZE_METHOD.equals(method)) {
+					return null;
+				}
+			}
+
+			Object target = ensureResolved();
+
+			if (target == null) {
+				return null;
+			}
+
+			ReflectionUtils.makeAccessible(method);
+
+			return method.invoke(target, args);
+		}
+
+		/**
+		 * Returns a to string representation for the given {@code proxy}.
+		 *
+		 * @param proxy
+		 * @return
+		 */
+		private String proxyToString(@Nullable Object proxy) {
+
+			StringBuilder description = new StringBuilder();
+			if (dbref != null) {
+				description.append(dbref.getCollectionName());
+				description.append(":");
+				description.append(dbref.getId());
+			} else {
+				description.append(System.identityHashCode(proxy));
+			}
+			description.append("$").append(LazyLoadingProxy.class.getSimpleName());
+
+			return description.toString();
+		}
+
+		/**
+		 * Returns the hashcode for the given {@code proxy}.
+		 *
+		 * @param proxy
+		 * @return
+		 */
+		private int proxyHashCode(@Nullable Object proxy) {
+			return proxyToString(proxy).hashCode();
+		}
+
+		/**
+		 * Performs an equality check for the given {@code proxy}.
+		 *
+		 * @param proxy
+		 * @param that
+		 * @return
+		 */
+		private boolean proxyEquals(@Nullable Object proxy, Object that) {
+
+			if (!(that instanceof LazyLoadingProxy)) {
+				return false;
+			}
+
+			if (that == proxy) {
+				return true;
+			}
+
+			return proxyToString(proxy).equals(that.toString());
+		}
+
+		/**
+		 * Will trigger the resolution if the proxy is not resolved already or return a previously resolved result.
+		 *
+		 * @return
+		 */
+		@Nullable
+		private Object ensureResolved() {
+
+			if (!resolved) {
+				this.result = resolve();
+				this.resolved = true;
+			}
+
+			return this.result;
+		}
+
+		/**
+		 * Callback method for serialization.
+		 *
+		 * @param out
+		 * @throws IOException
+		 */
+		private void writeObject(ObjectOutputStream out) throws IOException {
+
+			ensureResolved();
+			out.writeObject(this.result);
+		}
+
+		/**
+		 * Callback method for deserialization.
+		 *
+		 * @param in
+		 * @throws IOException
+		 */
+		private void readObject(ObjectInputStream in) throws IOException {
+
+			try {
+				this.resolved = true;
+				this.result = in.readObject();
+			} catch (ClassNotFoundException e) {
+				throw new LazyLoadingException("Could not deserialize result", e);
+			}
+		}
+
+		/**
+		 * Resolves the proxy into its backing object.
+		 *
+		 * @return
+		 */
+		@Nullable
+		private synchronized Object resolve() {
+
+			if (resolved) {
+
+				if (LOGGER.isTraceEnabled()) {
+					LOGGER.trace("Accessing already resolved lazy loading property {}.{}",
+							property.getOwner() != null ? property.getOwner().getName() : "unknown", property.getName());
+				}
+				return result;
+			}
+
+			try {
+				if (LOGGER.isTraceEnabled()) {
+					LOGGER.trace("Resolving lazy loading property {}.{}",
+							property.getOwner() != null ? property.getOwner().getName() : "unknown", property.getName());
+				}
+
+				return callback.resolve(property);
+
+			} catch (RuntimeException ex) {
+
+				DataAccessException translatedException = this.exceptionTranslator.translateExceptionIfPossible(ex);
+
+				if (translatedException instanceof ClientSessionException) {
+					throw new LazyLoadingException("Unable to lazily resolve DBRef! Invalid session state.", ex);
+				}
+
+				throw new LazyLoadingException("Unable to lazily resolve DBRef!",
+						translatedException != null ? translatedException : ex);
+			}
+		}
+	}
+
 	/**
 	 * Customization hook for obtaining the {@link MongoCollection} for a given {@link DBRef}.
 	 *
@@ -198,10 +504,4 @@ public class DefaultDbRefResolver extends DefaultReferenceResolver implements Db
 		return MongoDatabaseUtils.getDatabase(dbref.getDatabaseName(), mongoDbFactory)
 				.getCollection(dbref.getCollectionName(), Document.class);
 	}
-
-	protected MongoCollection<Document> getCollection(ReferenceCollection context) {
-
-		return MongoDatabaseUtils.getDatabase(context.getDatabase(), mongoDbFactory).getCollection(context.getCollection(),
-				Document.class);
-	}
 }

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/convert/DefaultReferenceResolver.java

@@ -1,113 +0,0 @@
-/*
- * Copyright 2021 the original author or authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      https://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.springframework.data.mongodb.core.convert;
-
-import static org.springframework.data.mongodb.core.convert.ReferenceLookupDelegate.*;
-
-import java.util.Collections;
-
-import org.springframework.dao.support.PersistenceExceptionTranslator;
-import org.springframework.data.mongodb.core.mapping.DBRef;
-import org.springframework.data.mongodb.core.mapping.DocumentReference;
-import org.springframework.data.mongodb.core.mapping.MongoPersistentProperty;
-import org.springframework.util.Assert;
-
-/**
- * {@link ReferenceResolver} implementation that uses a given {@link ReferenceLookupDelegate} to load and convert entity
- * associations expressed via a {@link MongoPersistentProperty persitent property}. Creates {@link LazyLoadingProxy
- * proxies} for associations that should be lazily loaded.
- *
- * @author Christoph Strobl
- * @author Mark Paluch
- * @since 3.3
- */
-public class DefaultReferenceResolver implements ReferenceResolver {
-
-	private final ReferenceLoader referenceLoader;
-	private final LazyLoadingProxyFactory proxyFactory;
-
-	private final LookupFunction collectionLookupFunction = (filter, ctx) -> getReferenceLoader().fetchMany(filter, ctx);
-	private final LookupFunction singleValueLookupFunction = (filter, ctx) -> {
-		Object target = getReferenceLoader().fetchOne(filter, ctx);
-		return target == null ? Collections.emptyList() : Collections.singleton(getReferenceLoader().fetchOne(filter, ctx));
-	};
-
-	/**
-	 * Create a new instance of {@link DefaultReferenceResolver}.
-	 *
-	 * @param referenceLoader must not be {@literal null}.
-	 * @param exceptionTranslator must not be {@literal null}.
-	 */
-	public DefaultReferenceResolver(ReferenceLoader referenceLoader, PersistenceExceptionTranslator exceptionTranslator) {
-
-		Assert.notNull(referenceLoader, "ReferenceLoader must not be null!");
-		Assert.notNull(exceptionTranslator, "ExceptionTranslator must not be null!");
-
-		this.referenceLoader = referenceLoader;
-		this.proxyFactory = new LazyLoadingProxyFactory(exceptionTranslator);
-	}
-
-	@Override
-	public Object resolveReference(MongoPersistentProperty property, Object source,
-			ReferenceLookupDelegate referenceLookupDelegate, MongoEntityReader entityReader) {
-
-		LookupFunction lookupFunction = (property.isCollectionLike() || property.isMap()) ? collectionLookupFunction
-				: singleValueLookupFunction;
-
-		if (isLazyReference(property)) {
-			return createLazyLoadingProxy(property, source, referenceLookupDelegate, lookupFunction, entityReader);
-		}
-
-		return referenceLookupDelegate.readReference(property, source, lookupFunction, entityReader);
-	}
-
-	/**
-	 * Check if the association expressed by the given {@link MongoPersistentProperty property} should be resolved lazily.
-	 *
-	 * @param property
-	 * @return return {@literal true} if the defined association is lazy.
-	 * @see DBRef#lazy()
-	 * @see DocumentReference#lazy()
-	 */
-	protected boolean isLazyReference(MongoPersistentProperty property) {
-
-		if (property.isDocumentReference()) {
-			return property.getDocumentReference().lazy();
-		}
-
-		return property.getDBRef() != null && property.getDBRef().lazy();
-	}
-
-	/**
-	 * The {@link ReferenceLoader} executing the lookup.
-	 *
-	 * @return never {@literal null}.
-	 */
-	protected ReferenceLoader getReferenceLoader() {
-		return referenceLoader;
-	}
-
-	LazyLoadingProxyFactory getProxyFactory() {
-		return proxyFactory;
-	}
-
-	private Object createLazyLoadingProxy(MongoPersistentProperty property, Object source,
-			ReferenceLookupDelegate referenceLookupDelegate, LookupFunction lookupFunction, MongoEntityReader entityReader) {
-		return proxyFactory.createLazyLoadingProxy(property, it -> {
-			return referenceLookupDelegate.readReference(it, source, lookupFunction, entityReader);
-		}, source);
-	}
-}

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/convert/DocumentAccessor.java

@@ -17,7 +17,6 @@ package org.springframework.data.mongodb.core.convert;
 
 import java.util.Arrays;
 import java.util.Iterator;
-import java.util.Map;
 
 import org.bson.Document;
 import org.bson.conversions.Bson;
@@ -67,19 +66,6 @@ class DocumentAccessor {
 		return this.document;
 	}
 
-	/**
-	 * Copies all of the mappings from the given {@link Document} to the underlying target {@link Document}. These
-	 * mappings will replace any mappings that the target document had for any of the keys currently in the specified map.
-	 *
-	 * @param source
-	 */
-	public void putAll(Document source) {
-
-		Map<String, Object> target = BsonUtils.asMap(document);
-
-		target.putAll(source);
-	}
-
 	/**
 	 * Puts the given value into the backing {@link Document} based on the coordinates defined through the given
 	 * {@link MongoPersistentProperty}. By default this will be the plain field name. But field names might also consist
@@ -133,7 +119,6 @@ class DocumentAccessor {
 	 * @param entity must not be {@literal null}.
 	 * @return
 	 */
-	@Nullable
 	public Object getRawId(MongoPersistentEntity<?> entity) {
 		return entity.hasIdProperty() ? get(entity.getRequiredIdProperty()) : BsonUtils.asMap(document).get("_id");
 	}

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/convert/DocumentPointerFactory.java

@@ -1,237 +0,0 @@
-/*
- * Copyright 2021 the original author or authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      https://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.springframework.data.mongodb.core.convert;
-
-import java.util.LinkedHashMap;
-import java.util.Map;
-import java.util.Map.Entry;
-import java.util.WeakHashMap;
-import java.util.regex.Matcher;
-import java.util.regex.Pattern;
-
-import org.bson.Document;
-import org.springframework.core.convert.ConversionService;
-import org.springframework.dao.InvalidDataAccessApiUsageException;
-import org.springframework.data.annotation.Reference;
-import org.springframework.data.mapping.PersistentPropertyAccessor;
-import org.springframework.data.mapping.PersistentPropertyPath;
-import org.springframework.data.mapping.PropertyPath;
-import org.springframework.data.mapping.context.MappingContext;
-import org.springframework.data.mapping.model.BeanWrapperPropertyAccessorFactory;
-import org.springframework.data.mongodb.core.mapping.DocumentPointer;
-import org.springframework.data.mongodb.core.mapping.MongoPersistentEntity;
-import org.springframework.data.mongodb.core.mapping.MongoPersistentProperty;
-
-/**
- * Internal API to construct {@link DocumentPointer} for a given property. Considers {@link LazyLoadingProxy},
- * registered {@link Object} to {@link DocumentPointer} {@link org.springframework.core.convert.converter.Converter},
- * simple {@literal _id} lookups and cases where the {@link DocumentPointer} needs to be computed via a lookup query.
- *
- * @author Christoph Strobl
- * @since 3.3
- */
-class DocumentPointerFactory {
-
-	private final ConversionService conversionService;
-	private final MappingContext<? extends MongoPersistentEntity<?>, MongoPersistentProperty> mappingContext;
-	private final Map<String, LinkageDocument> cache;
-
-	/**
-	 * A {@link Pattern} matching quoted and unquoted variants (with/out whitespaces) of
-	 * <code>{'_id' : ?#{#target} }</code>.
-	 */
-	private static final Pattern DEFAULT_LOOKUP_PATTERN = Pattern.compile("\\{\\s?" + // document start (whitespace opt)
-			"['\"]?_id['\"]?" + // followed by an optionally quoted _id. Like: _id, '_id' or "_id"
-			"?\\s?:\\s?" + // then a colon optionally wrapped inside whitespaces
-			"['\"]?\\?#\\{#target\\}['\"]?" + // leading to the potentially quoted ?#{#target} expression
-			"\\s*}"); // some optional whitespaces and document close
-
-	DocumentPointerFactory(ConversionService conversionService,
-			MappingContext<? extends MongoPersistentEntity<?>, MongoPersistentProperty> mappingContext) {
-
-		this.conversionService = conversionService;
-		this.mappingContext = mappingContext;
-		this.cache = new WeakHashMap<>();
-	}
-
-	DocumentPointer<?> computePointer(
-			MappingContext<? extends MongoPersistentEntity<?>, MongoPersistentProperty> mappingContext,
-			MongoPersistentProperty property, Object value, Class<?> typeHint) {
-
-		if (value instanceof LazyLoadingProxy) {
-			return () -> ((LazyLoadingProxy) value).getSource();
-		}
-
-		if (conversionService.canConvert(typeHint, DocumentPointer.class)) {
-			return conversionService.convert(value, DocumentPointer.class);
-		}
-
-		MongoPersistentEntity<?> persistentEntity = mappingContext
-				.getRequiredPersistentEntity(property.getAssociationTargetType());
-
-		if (usesDefaultLookup(property)) {
-			return () -> persistentEntity.getIdentifierAccessor(value).getIdentifier();
-		}
-
-		MongoPersistentEntity<?> valueEntity = mappingContext.getPersistentEntity(value.getClass());
-		PersistentPropertyAccessor<Object> propertyAccessor;
-		if (valueEntity == null) {
-			propertyAccessor = BeanWrapperPropertyAccessorFactory.INSTANCE.getPropertyAccessor(property.getOwner(), value);
-		} else {
-			propertyAccessor = valueEntity.getPropertyPathAccessor(value);
-		}
-
-		return cache.computeIfAbsent(property.getDocumentReference().lookup(), LinkageDocument::from)
-				.getDocumentPointer(mappingContext, persistentEntity, propertyAccessor);
-	}
-
-	private boolean usesDefaultLookup(MongoPersistentProperty property) {
-
-		if (property.isDocumentReference()) {
-			return DEFAULT_LOOKUP_PATTERN.matcher(property.getDocumentReference().lookup()).matches();
-		}
-
-		Reference atReference = property.findAnnotation(Reference.class);
-		if (atReference != null) {
-			return true;
-		}
-
-		throw new IllegalStateException(String.format("%s does not seem to be define Reference", property));
-	}
-
-	/**
-	 * Value object that computes a document pointer from a given lookup query by identifying SpEL expressions and
-	 * inverting it.
-	 * 
-	 * <pre class="code">
-	 * // source
-	 * { 'firstname' : ?#{fn}, 'lastname' : '?#{ln} }
-	 * 
-	 * // target
-	 * { 'fn' : ..., 'ln' : ... }
-	 * </pre>
-	 * 
-	 * The actual pointer is the computed via
-	 * {@link #getDocumentPointer(MappingContext, MongoPersistentEntity, PersistentPropertyAccessor)} applying values from
-	 * the provided {@link PersistentPropertyAccessor} to the target document by looking at the keys of the expressions
-	 * from the source.
-	 */
-	static class LinkageDocument {
-
-		static final Pattern EXPRESSION_PATTERN = Pattern.compile("\\?#\\{#?(?<fieldName>[\\w\\d\\.\\-)]*)\\}");
-		static final Pattern PLACEHOLDER_PATTERN = Pattern.compile("###_(?<index>\\d*)_###");
-
-		private final String lookup;
-		private final org.bson.Document documentPointer;
-		private final Map<String, String> placeholderMap;
-
-		static LinkageDocument from(String lookup) {
-			return new LinkageDocument(lookup);
-		}
-
-		private LinkageDocument(String lookup) {
-
-			this.lookup = lookup;
-			this.placeholderMap = new LinkedHashMap<>();
-
-			int index = 0;
-			Matcher matcher = EXPRESSION_PATTERN.matcher(lookup);
-			String targetLookup = lookup;
-
-			while (matcher.find()) {
-
-				String expression = matcher.group();
-				String fieldName = matcher.group("fieldName").replace("target.", "");
-
-				String placeholder = placeholder(index);
-				placeholderMap.put(placeholder, fieldName);
-				targetLookup = targetLookup.replace(expression, "'" + placeholder + "'");
-				index++;
-			}
-
-			this.documentPointer = org.bson.Document.parse(targetLookup);
-		}
-
-		private String placeholder(int index) {
-			return "###_" + index + "_###";
-		}
-
-		private boolean isPlaceholder(String key) {
-			return PLACEHOLDER_PATTERN.matcher(key).matches();
-		}
-
-		DocumentPointer<Object> getDocumentPointer(
-				MappingContext<? extends MongoPersistentEntity<?>, MongoPersistentProperty> mappingContext,
-				MongoPersistentEntity<?> persistentEntity, PersistentPropertyAccessor<?> propertyAccessor) {
-			return () -> updatePlaceholders(documentPointer, new Document(), mappingContext, persistentEntity,
-					propertyAccessor);
-		}
-
-		Document updatePlaceholders(org.bson.Document source, org.bson.Document target,
-				MappingContext<? extends MongoPersistentEntity<?>, MongoPersistentProperty> mappingContext,
-				MongoPersistentEntity<?> persistentEntity, PersistentPropertyAccessor<?> propertyAccessor) {
-
-			for (Entry<String, Object> entry : source.entrySet()) {
-
-				if (entry.getKey().startsWith("$")) {
-					throw new InvalidDataAccessApiUsageException(String.format(
-							"Cannot derive document pointer from lookup '%s' using query operator (%s). Please consider registering a custom converter.",
-							lookup, entry.getKey()));
-				}
-
-				if (entry.getValue() instanceof Document) {
-
-					MongoPersistentProperty persistentProperty = persistentEntity.getPersistentProperty(entry.getKey());
-					if (persistentProperty != null && persistentProperty.isEntity()) {
-
-						MongoPersistentEntity<?> nestedEntity = mappingContext.getPersistentEntity(persistentProperty.getType());
-						target.put(entry.getKey(), updatePlaceholders((Document) entry.getValue(), new Document(), mappingContext,
-								nestedEntity, nestedEntity.getPropertyAccessor(propertyAccessor.getProperty(persistentProperty))));
-					} else {
-						target.put(entry.getKey(), updatePlaceholders((Document) entry.getValue(), new Document(), mappingContext,
-								persistentEntity, propertyAccessor));
-					}
-					continue;
-				}
-
-				if (placeholderMap.containsKey(entry.getValue())) {
-
-					String attribute = placeholderMap.get(entry.getValue());
-					if (attribute.contains(".")) {
-						attribute = attribute.substring(attribute.lastIndexOf('.') + 1);
-					}
-
-					String fieldName = entry.getKey().equals("_id") ? "id" : entry.getKey();
-					if (!fieldName.contains(".")) {
-
-						Object targetValue = propertyAccessor.getProperty(persistentEntity.getPersistentProperty(fieldName));
-						target.put(attribute, targetValue);
-						continue;
-					}
-
-					PersistentPropertyPath<?> path = mappingContext
-							.getPersistentPropertyPath(PropertyPath.from(fieldName, persistentEntity.getTypeInformation()));
-					Object targetValue = propertyAccessor.getProperty(path);
-					target.put(attribute, targetValue);
-					continue;
-				}
-
-				target.put(entry.getKey(), entry.getValue());
-			}
-			return target;
-		}
-	}
-}

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/convert/LazyLoadingProxy.java

@@ -15,18 +15,18 @@
  */
 package org.springframework.data.mongodb.core.convert;
 
+import org.springframework.data.mongodb.core.convert.DefaultDbRefResolver.LazyLoadingInterceptor;
 import org.springframework.lang.Nullable;
 
 import com.mongodb.DBRef;
 
 /**
- * Allows direct interaction with the underlying {@code LazyLoadingInterceptor}.
+ * Allows direct interaction with the underlying {@link LazyLoadingInterceptor}.
  *
  * @author Thomas Darimont
  * @author Christoph Strobl
  * @author Mark Paluch
  * @since 1.5
- * @see LazyLoadingProxyFactory
  */
 public interface LazyLoadingProxy {
 
@@ -46,15 +46,4 @@ public interface LazyLoadingProxy {
 	 */
 	@Nullable
 	DBRef toDBRef();
-
-	/**
-	 * Returns the raw {@literal source} object that defines the reference.
-	 *
-	 * @return can be {@literal null}.
-	 * @since 3.3
-	 */
-	@Nullable
-	default Object getSource() {
-		return toDBRef();
-	}
 }

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/convert/LazyLoadingProxyFactory.java

@@ -1,303 +0,0 @@
-/*
- * Copyright 2021 the original author or authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      https://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.springframework.data.mongodb.core.convert;
-
-import static org.springframework.util.ReflectionUtils.*;
-
-import java.io.IOException;
-import java.io.ObjectInputStream;
-import java.io.ObjectOutputStream;
-import java.io.Serializable;
-import java.lang.reflect.Method;
-
-import org.aopalliance.intercept.MethodInterceptor;
-import org.aopalliance.intercept.MethodInvocation;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
-import org.springframework.aop.framework.ProxyFactory;
-import org.springframework.cglib.proxy.Callback;
-import org.springframework.cglib.proxy.Enhancer;
-import org.springframework.cglib.proxy.Factory;
-import org.springframework.cglib.proxy.MethodProxy;
-import org.springframework.dao.DataAccessException;
-import org.springframework.dao.support.PersistenceExceptionTranslator;
-import org.springframework.data.mongodb.ClientSessionException;
-import org.springframework.data.mongodb.LazyLoadingException;
-import org.springframework.data.mongodb.core.mapping.MongoPersistentProperty;
-import org.springframework.lang.Nullable;
-import org.springframework.objenesis.ObjenesisStd;
-import org.springframework.util.ReflectionUtils;
-
-import com.mongodb.DBRef;
-
-/**
- * {@link ProxyFactory} to create a proxy for {@link MongoPersistentProperty#getType()} to resolve a reference lazily.
- *
- * @author Christoph Strobl
- * @author Mark Paluch
- */
-class LazyLoadingProxyFactory {
-
-	private static final Logger LOGGER = LoggerFactory.getLogger(LazyLoadingProxyFactory.class);
-
-	private final ObjenesisStd objenesis;
-
-	private final PersistenceExceptionTranslator exceptionTranslator;
-
-	public LazyLoadingProxyFactory(PersistenceExceptionTranslator exceptionTranslator) {
-		this.exceptionTranslator = exceptionTranslator;
-		this.objenesis = new ObjenesisStd(true);
-	}
-
-	public Object createLazyLoadingProxy(MongoPersistentProperty property, DbRefResolverCallback callback,
-			Object source) {
-
-		Class<?> propertyType = property.getType();
-		LazyLoadingInterceptor interceptor = new LazyLoadingInterceptor(property, callback, source, exceptionTranslator);
-
-		if (!propertyType.isInterface()) {
-
-			Factory factory = (Factory) objenesis.newInstance(getEnhancedTypeFor(propertyType));
-			factory.setCallbacks(new Callback[] { interceptor });
-
-			return factory;
-		}
-
-		ProxyFactory proxyFactory = new ProxyFactory();
-
-		for (Class<?> type : propertyType.getInterfaces()) {
-			proxyFactory.addInterface(type);
-		}
-
-		proxyFactory.addInterface(LazyLoadingProxy.class);
-		proxyFactory.addInterface(propertyType);
-		proxyFactory.addAdvice(interceptor);
-
-		return proxyFactory.getProxy(LazyLoadingProxy.class.getClassLoader());
-	}
-
-	/**
-	 * Returns the CGLib enhanced type for the given source type.
-	 *
-	 * @param type
-	 * @return
-	 */
-	private Class<?> getEnhancedTypeFor(Class<?> type) {
-
-		Enhancer enhancer = new Enhancer();
-		enhancer.setSuperclass(type);
-		enhancer.setCallbackType(org.springframework.cglib.proxy.MethodInterceptor.class);
-		enhancer.setInterfaces(new Class[] { LazyLoadingProxy.class });
-
-		return enhancer.createClass();
-	}
-
-	public static class LazyLoadingInterceptor
-			implements MethodInterceptor, org.springframework.cglib.proxy.MethodInterceptor, Serializable {
-
-		private static final Method INITIALIZE_METHOD, TO_DBREF_METHOD, FINALIZE_METHOD, GET_SOURCE_METHOD;
-
-		static {
-			try {
-				INITIALIZE_METHOD = LazyLoadingProxy.class.getMethod("getTarget");
-				TO_DBREF_METHOD = LazyLoadingProxy.class.getMethod("toDBRef");
-				FINALIZE_METHOD = Object.class.getDeclaredMethod("finalize");
-				GET_SOURCE_METHOD = LazyLoadingProxy.class.getMethod("getSource");
-			} catch (Exception e) {
-				throw new RuntimeException(e);
-			}
-		}
-
-		private final MongoPersistentProperty property;
-		private final DbRefResolverCallback callback;
-		private final Object source;
-		private final PersistenceExceptionTranslator exceptionTranslator;
-		private volatile boolean resolved;
-		private @Nullable Object result;
-
-		public LazyLoadingInterceptor(MongoPersistentProperty property, DbRefResolverCallback callback, Object source,
-				PersistenceExceptionTranslator exceptionTranslator) {
-
-			this.property = property;
-			this.callback = callback;
-			this.source = source;
-			this.exceptionTranslator = exceptionTranslator;
-		}
-
-		@Nullable
-		@Override
-		public Object invoke(MethodInvocation invocation) throws Throwable {
-			return intercept(invocation.getThis(), invocation.getMethod(), invocation.getArguments(), null);
-		}
-
-		@Nullable
-		@Override
-		public Object intercept(Object o, Method method, Object[] args, MethodProxy proxy) throws Throwable {
-
-			if (INITIALIZE_METHOD.equals(method)) {
-				return ensureResolved();
-			}
-
-			if (TO_DBREF_METHOD.equals(method)) {
-				return source instanceof DBRef ? source : null;
-			}
-
-			if (GET_SOURCE_METHOD.equals(method)) {
-				return source;
-			}
-
-			if (isObjectMethod(method) && Object.class.equals(method.getDeclaringClass())) {
-
-				if (ReflectionUtils.isToStringMethod(method)) {
-					return proxyToString(source);
-				}
-
-				if (ReflectionUtils.isEqualsMethod(method)) {
-					return proxyEquals(o, args[0]);
-				}
-
-				if (ReflectionUtils.isHashCodeMethod(method)) {
-					return proxyHashCode();
-				}
-
-				// DATAMONGO-1076 - finalize methods should not trigger proxy initialization
-				if (FINALIZE_METHOD.equals(method)) {
-					return null;
-				}
-			}
-
-			Object target = ensureResolved();
-
-			if (target == null) {
-				return null;
-			}
-
-			ReflectionUtils.makeAccessible(method);
-
-			return method.invoke(target, args);
-		}
-
-		@Nullable
-		private Object ensureResolved() {
-
-			if (!resolved) {
-				this.result = resolve();
-				this.resolved = true;
-			}
-
-			return this.result;
-		}
-
-		private String proxyToString(@Nullable Object source) {
-
-			StringBuilder description = new StringBuilder();
-			if (source != null) {
-				if (source instanceof DBRef) {
-					description.append(((DBRef) source).getCollectionName());
-					description.append(":");
-					description.append(((DBRef) source).getId());
-				} else {
-					description.append(source);
-				}
-			} else {
-				description.append(System.identityHashCode(source));
-			}
-			description.append("$").append(LazyLoadingProxy.class.getSimpleName());
-
-			return description.toString();
-		}
-
-		private boolean proxyEquals(@Nullable Object proxy, Object that) {
-
-			if (!(that instanceof LazyLoadingProxy)) {
-				return false;
-			}
-
-			if (that == proxy) {
-				return true;
-			}
-
-			return proxyToString(proxy).equals(that.toString());
-		}
-
-		private int proxyHashCode() {
-			return proxyToString(source).hashCode();
-		}
-
-		/**
-		 * Callback method for serialization.
-		 *
-		 * @param out
-		 * @throws IOException
-		 */
-		private void writeObject(ObjectOutputStream out) throws IOException {
-
-			ensureResolved();
-			out.writeObject(this.result);
-		}
-
-		/**
-		 * Callback method for deserialization.
-		 *
-		 * @param in
-		 * @throws IOException
-		 */
-		private void readObject(ObjectInputStream in) throws IOException {
-
-			try {
-				this.resolved = true;
-				this.result = in.readObject();
-			} catch (ClassNotFoundException e) {
-				throw new LazyLoadingException("Could not deserialize result", e);
-			}
-		}
-
-		@Nullable
-		private synchronized Object resolve() {
-
-			if (resolved) {
-
-				if (LOGGER.isTraceEnabled()) {
-					LOGGER.trace("Accessing already resolved lazy loading property {}.{}",
-							property.getOwner() != null ? property.getOwner().getName() : "unknown", property.getName());
-				}
-				return result;
-			}
-
-			try {
-				if (LOGGER.isTraceEnabled()) {
-					LOGGER.trace("Resolving lazy loading property {}.{}",
-							property.getOwner() != null ? property.getOwner().getName() : "unknown", property.getName());
-				}
-
-				return callback.resolve(property);
-
-			} catch (RuntimeException ex) {
-
-				DataAccessException translatedException = exceptionTranslator.translateExceptionIfPossible(ex);
-
-				if (translatedException instanceof ClientSessionException) {
-					throw new LazyLoadingException("Unable to lazily resolve DBRef! Invalid session state.", ex);
-				}
-
-				throw new LazyLoadingException("Unable to lazily resolve DBRef!",
-						translatedException != null ? translatedException : ex);
-			}
-		}
-	}
-
-}

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/convert/MongoConverter.java

@@ -26,7 +26,6 @@ import org.springframework.data.convert.TypeMapper;
 import org.springframework.data.mongodb.core.mapping.MongoPersistentEntity;
 import org.springframework.data.mongodb.core.mapping.MongoPersistentProperty;
 import org.springframework.data.mongodb.util.BsonUtils;
-import org.springframework.data.util.TypeInformation;
 import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 import org.springframework.util.ClassUtils;
@@ -145,9 +144,9 @@ public interface MongoConverter
 		try {
 			return getConversionService().canConvert(id.getClass(), targetType)
 					? getConversionService().convert(id, targetType)
-					: convertToMongoType(id, (TypeInformation<?>) null);
+					: convertToMongoType(id, null);
 		} catch (ConversionException o_O) {
-			return convertToMongoType(id,(TypeInformation<?>)  null);
+			return convertToMongoType(id, null);
 		}
 	}
 }

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/convert/MongoConverters.java

@@ -27,18 +27,14 @@ import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Currency;
 import java.util.List;
-import java.util.UUID;
 import java.util.concurrent.atomic.AtomicInteger;
 import java.util.concurrent.atomic.AtomicLong;
 
-import org.bson.BsonReader;
 import org.bson.BsonTimestamp;
-import org.bson.BsonWriter;
 import org.bson.Document;
+import org.bson.UuidRepresentation;
 import org.bson.codecs.Codec;
-import org.bson.codecs.DecoderContext;
-import org.bson.codecs.EncoderContext;
-import org.bson.codecs.configuration.CodecRegistries;
+import org.bson.internal.CodecRegistryHelper;
 import org.bson.types.Binary;
 import org.bson.types.Code;
 import org.bson.types.Decimal128;
@@ -244,23 +240,9 @@ abstract class MongoConverters {
 
 		INSTANCE;
 
-		private final Codec<Document> codec = CodecRegistries.fromRegistries(CodecRegistries.fromCodecs(new Codec<UUID>() {
-
-			@Override
-			public void encode(BsonWriter writer, UUID value, EncoderContext encoderContext) {
-				writer.writeString(value.toString());
-			}
-
-			@Override
-			public Class<UUID> getEncoderClass() {
-				return UUID.class;
-			}
-
-			@Override
-			public UUID decode(BsonReader reader, DecoderContext decoderContext) {
-				throw new IllegalStateException("decode not supported");
-			}
-		}), MongoClientSettings.getDefaultCodecRegistry()).get(Document.class);
+		private final Codec<Document> codec = CodecRegistryHelper
+				.createRegistry(MongoClientSettings.getDefaultCodecRegistry(), UuidRepresentation.JAVA_LEGACY)
+				.get(Document.class);
 
 		@Override
 		public String convert(Document source) {
@@ -294,7 +276,7 @@ abstract class MongoConverters {
 		@Override
 		public NamedMongoScript convert(Document source) {
 
-			if (source.isEmpty()) {
+			if(source.isEmpty()) {
 				return null;
 			}
 

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/convert/MongoDatabaseFactoryReferenceLoader.java

@@ -1,79 +0,0 @@
-/*
- * Copyright 2021 the original author or authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      https://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.springframework.data.mongodb.core.convert;
-
-import org.bson.Document;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-import org.springframework.data.mongodb.MongoDatabaseFactory;
-import org.springframework.data.mongodb.MongoDatabaseUtils;
-import org.springframework.data.mongodb.core.convert.ReferenceResolver.ReferenceCollection;
-import org.springframework.util.Assert;
-import org.springframework.util.StringUtils;
-
-import com.mongodb.client.MongoCollection;
-
-/**
- * {@link ReferenceLoader} implementation using a {@link MongoDatabaseFactory} to obtain raw {@link Document documents}
- * for linked entities via a {@link ReferenceLoader.DocumentReferenceQuery}.
- *
- * @author Christoph Strobl
- * @since 3.3
- */
-public class MongoDatabaseFactoryReferenceLoader implements ReferenceLoader {
-
-	private static final Logger LOGGER = LoggerFactory.getLogger(MongoDatabaseFactoryReferenceLoader.class);
-
-	private final MongoDatabaseFactory mongoDbFactory;
-
-	/**
-	 * @param mongoDbFactory must not be {@literal null}.
-	 */
-	public MongoDatabaseFactoryReferenceLoader(MongoDatabaseFactory mongoDbFactory) {
-
-		Assert.notNull(mongoDbFactory, "MongoDbFactory translator must not be null!");
-
-		this.mongoDbFactory = mongoDbFactory;
-	}
-
-	@Override
-	public Iterable<Document> fetchMany(DocumentReferenceQuery referenceQuery, ReferenceCollection context) {
-
-		MongoCollection<Document> collection = getCollection(context);
-
-		if (LOGGER.isTraceEnabled()) {
-			LOGGER.trace("Bulk fetching {} from {}.{}.", referenceQuery,
-					StringUtils.hasText(context.getDatabase()) ? context.getDatabase()
-							: collection.getNamespace().getDatabaseName(),
-					context.getCollection());
-		}
-
-		return referenceQuery.apply(collection);
-	}
-
-	/**
-	 * Obtain the {@link MongoCollection} for a given {@link ReferenceCollection} from the underlying
-	 * {@link MongoDatabaseFactory}.
-	 *
-	 * @param context must not be {@literal null}.
-	 * @return the {@link MongoCollection} targeted by the {@link ReferenceCollection}.
-	 */
-	protected MongoCollection<Document> getCollection(ReferenceCollection context) {
-
-		return MongoDatabaseUtils.getDatabase(context.getDatabase(), mongoDbFactory).getCollection(context.getCollection(),
-				Document.class);
-	}
-}

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/convert/MongoExampleMapper.java

@@ -40,7 +40,6 @@ import org.springframework.data.mongodb.core.query.MongoRegexCreator;
 import org.springframework.data.mongodb.core.query.MongoRegexCreator.MatchMode;
 import org.springframework.data.mongodb.core.query.SerializationUtils;
 import org.springframework.data.mongodb.core.query.UntypedExampleMatcher;
-import org.springframework.data.mongodb.util.DotPath;
 import org.springframework.data.support.ExampleMatcherAccessor;
 import org.springframework.data.util.TypeInformation;
 import org.springframework.util.Assert;
@@ -135,7 +134,7 @@ public class MongoExampleMapper {
 		while (iter.hasNext()) {
 
 			Map.Entry<String, Object> entry = iter.next();
-			String propertyPath = DotPath.from(path).append(entry.getKey()).toString();
+			String propertyPath = StringUtils.hasText(path) ? path + "." + entry.getKey() : entry.getKey();
 			String mappedPropertyPath = getMappedPropertyPath(propertyPath, probeType);
 
 			if (isEmptyIdProperty(entry)) {

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/convert/MongoWriter.java

@@ -17,9 +17,6 @@ package org.springframework.data.mongodb.core.convert;
 
 import org.bson.conversions.Bson;
 import org.springframework.data.convert.EntityWriter;
-import org.springframework.data.mongodb.core.mapping.DocumentPointer;
-import org.springframework.data.mongodb.core.mapping.DocumentReference;
-import org.springframework.data.mongodb.core.mapping.MongoPersistentEntity;
 import org.springframework.data.mongodb.core.mapping.MongoPersistentProperty;
 import org.springframework.data.util.TypeInformation;
 import org.springframework.lang.Nullable;
@@ -46,7 +43,7 @@ public interface MongoWriter<T> extends EntityWriter<T, Bson> {
 	 */
 	@Nullable
 	default Object convertToMongoType(@Nullable Object obj) {
-		return convertToMongoType(obj, (TypeInformation<?>) null);
+		return convertToMongoType(obj, null);
 	}
 
 	/**
@@ -60,10 +57,6 @@ public interface MongoWriter<T> extends EntityWriter<T, Bson> {
 	@Nullable
 	Object convertToMongoType(@Nullable Object obj, @Nullable TypeInformation<?> typeInformation);
 
-	default Object convertToMongoType(@Nullable Object obj, MongoPersistentEntity<?> entity) {
-		return convertToMongoType(obj, entity.getTypeInformation());
-	}
-
 	/**
 	 * Creates a {@link DBRef} to refer to the given object.
 	 *
@@ -73,17 +66,4 @@ public interface MongoWriter<T> extends EntityWriter<T, Bson> {
 	 * @return will never be {@literal null}.
 	 */
 	DBRef toDBRef(Object object, @Nullable MongoPersistentProperty referingProperty);
-
-	/**
-	 * Creates a the {@link DocumentPointer} representing the link to another entity.
-	 *
-	 * @param source the object to create a document link to.
-	 * @param referringProperty the client-side property referring to the object which might carry additional metadata for
-	 *          the {@link DBRef} object to create. Can be {@literal null}.
-	 * @return will never be {@literal null}.
-	 * @since 3.3
-	 */
-	default DocumentPointer<?> toDocumentPointer(Object source, @Nullable MongoPersistentProperty referringProperty) {
-		return () -> toDBRef(source, referringProperty);
-	}
 }

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/convert/NoOpDbRefResolver.java

@@ -18,7 +18,6 @@ package org.springframework.data.mongodb.core.convert;
 import java.util.List;
 
 import org.bson.Document;
-
 import org.springframework.data.mongodb.core.mapping.MongoPersistentProperty;
 import org.springframework.lang.Nullable;
 
@@ -70,11 +69,4 @@ public enum NoOpDbRefResolver implements DbRefResolver {
 	private <T> T handle() throws UnsupportedOperationException {
 		throw new UnsupportedOperationException("DBRef resolution is not supported!");
 	}
-
-	@Nullable
-	@Override
-	public Object resolveReference(MongoPersistentProperty property, Object source,
-			ReferenceLookupDelegate referenceLookupDelegate, MongoEntityReader entityReader) {
-		return null;
-	}
 }

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/convert/QueryMapper.java

@@ -29,7 +29,6 @@ import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.core.convert.ConversionService;
 import org.springframework.core.convert.converter.Converter;
-import org.springframework.data.annotation.Reference;
 import org.springframework.data.domain.Example;
 import org.springframework.data.mapping.Association;
 import org.springframework.data.mapping.MappingException;
@@ -40,14 +39,12 @@ import org.springframework.data.mapping.PropertyPath;
 import org.springframework.data.mapping.PropertyReferenceException;
 import org.springframework.data.mapping.context.InvalidPersistentPropertyPath;
 import org.springframework.data.mapping.context.MappingContext;
-import org.springframework.data.mongodb.MongoExpression;
 import org.springframework.data.mongodb.core.convert.MappingMongoConverter.NestedDocument;
 import org.springframework.data.mongodb.core.mapping.MongoPersistentEntity;
 import org.springframework.data.mongodb.core.mapping.MongoPersistentProperty;
 import org.springframework.data.mongodb.core.mapping.MongoPersistentProperty.PropertyToFieldNameConverter;
 import org.springframework.data.mongodb.core.query.Query;
 import org.springframework.data.mongodb.util.BsonUtils;
-import org.springframework.data.mongodb.util.DotPath;
 import org.springframework.data.util.ClassTypeInformation;
 import org.springframework.data.util.TypeInformation;
 import org.springframework.lang.Nullable;
@@ -149,23 +146,9 @@ public class QueryMapper {
 			try {
 
 				Field field = createPropertyField(entity, key, mappingContext);
+				Entry<String, Object> entry = getMappedObjectForField(field, BsonUtils.get(query, key));
 
-				// TODO: move to dedicated method
-				if (field.getProperty() != null && field.getProperty().isUnwrapped()) {
-
-					Object theNestedObject = BsonUtils.get(query, key);
-					Document mappedValue = (Document) getMappedValue(field, theNestedObject);
-					if (!StringUtils.hasText(field.getMappedKey())) {
-						result.putAll(mappedValue);
-					} else {
-						result.put(field.getMappedKey(), mappedValue);
-					}
-				} else {
-
-					Entry<String, Object> entry = getMappedObjectForField(field, BsonUtils.get(query, key));
-
-					result.put(entry.getKey(), entry.getValue());
-				}
+				result.put(entry.getKey(), entry.getValue());
 			} catch (InvalidPersistentPropertyPath invalidPathException) {
 
 				// in case the object has not already been mapped
@@ -196,7 +179,13 @@ public class QueryMapper {
 			return new Document();
 		}
 
-		Document mappedSort = mapFieldsToPropertyNames(sortObject, entity);
+		Document mappedSort = new Document();
+		for (Map.Entry<String, Object> entry : BsonUtils.asMap(sortObject).entrySet()) {
+
+			Field field = createPropertyField(entity, entry.getKey(), mappingContext);
+			mappedSort.put(field.getMappedKey(), entry.getValue());
+		}
+
 		mapMetaAttributes(mappedSort, entity, MetaMapping.WHEN_PRESENT);
 		return mappedSort;
 	}
@@ -214,30 +203,11 @@ public class QueryMapper {
 
 		Assert.notNull(fieldsObject, "FieldsObject must not be null!");
 
-		Document mappedFields = mapFieldsToPropertyNames(fieldsObject, entity);
+		Document mappedFields = fieldsObject.isEmpty() ? new Document() : getMappedObject(fieldsObject, entity);
 		mapMetaAttributes(mappedFields, entity, MetaMapping.FORCE);
 		return mappedFields;
 	}
 
-	private Document mapFieldsToPropertyNames(Document fields, @Nullable MongoPersistentEntity<?> entity) {
-
-		if (fields.isEmpty()) {
-			return new Document();
-
-		}
-		Document target = new Document();
-		for (Map.Entry<String, Object> entry : BsonUtils.asMap(filterUnwrappedObjects(fields, entity)).entrySet()) {
-
-			Field field = createPropertyField(entity, entry.getKey(), mappingContext);
-			if (field.getProperty() != null && field.getProperty().isUnwrapped()) {
-				continue;
-			}
-
-			target.put(field.getMappedKey(), entry.getValue());
-		}
-		return target;
-	}
-
 	private void mapMetaAttributes(Document source, @Nullable MongoPersistentEntity<?> entity, MetaMapping metaMapping) {
 
 		if (entity == null) {
@@ -253,44 +223,6 @@ public class QueryMapper {
 		}
 	}
 
-	private Document filterUnwrappedObjects(Document fieldsObject, @Nullable MongoPersistentEntity<?> entity) {
-
-		if (fieldsObject.isEmpty() || entity == null) {
-			return fieldsObject;
-		}
-
-		Document target = new Document();
-
-		for (Entry<String, Object> field : fieldsObject.entrySet()) {
-
-			try {
-
-				PropertyPath path = PropertyPath.from(field.getKey(), entity.getTypeInformation());
-				PersistentPropertyPath<MongoPersistentProperty> persistentPropertyPath = mappingContext
-						.getPersistentPropertyPath(path);
-				MongoPersistentProperty property = mappingContext.getPersistentPropertyPath(path).getRequiredLeafProperty();
-
-				if (property.isUnwrapped() && property.isEntity()) {
-
-					MongoPersistentEntity<?> unwrappedEntity = mappingContext.getRequiredPersistentEntity(property);
-
-					for (MongoPersistentProperty unwrappedProperty : unwrappedEntity) {
-
-						DotPath dotPath = DotPath.from(persistentPropertyPath.toDotPath()).append(unwrappedProperty.getName());
-						target.put(dotPath.toString(), field.getValue());
-					}
-
-				} else {
-					target.put(field.getKey(), field.getValue());
-				}
-			} catch (RuntimeException e) {
-				target.put(field.getKey(), field.getValue());
-			}
-
-		}
-		return target;
-	}
-
 	private Document getMappedTextScoreField(MongoPersistentProperty property) {
 		return new Document(property.getFieldName(), META_TEXT_SCORE);
 	}
@@ -307,10 +239,6 @@ public class QueryMapper {
 		String key = field.getMappedKey();
 		Object value;
 
-		if (rawValue instanceof MongoExpression) {
-			return createMapEntry(key, getMappedObject(((MongoExpression) rawValue).toDocument(), field.getEntity()));
-		}
-
 		if (isNestedKeyword(rawValue) && !field.isIdField()) {
 			Keyword keyword = new Keyword((Document) rawValue);
 			value = getMappedKeyword(field, keyword);
@@ -579,11 +507,6 @@ public class QueryMapper {
 	 */
 	@Nullable
 	protected Object delegateConvertToMongoType(Object source, @Nullable MongoPersistentEntity<?> entity) {
-
-		if (entity != null && entity.isUnwrapped()) {
-			return converter.convertToMongoType(source, entity);
-		}
-
 		return converter.convertToMongoType(source, entity == null ? null : entity.getTypeInformation());
 	}
 
@@ -621,7 +544,7 @@ public class QueryMapper {
 		if (source instanceof Iterable) {
 			BasicDBList result = new BasicDBList();
 			for (Object element : (Iterable<?>) source) {
-				result.add(createReferenceFor(element, property));
+				result.add(createDbRefFor(element, property));
 			}
 			return result;
 		}
@@ -630,12 +553,12 @@ public class QueryMapper {
 			Document result = new Document();
 			Document dbObject = (Document) source;
 			for (String key : dbObject.keySet()) {
-				result.put(key, createReferenceFor(dbObject.get(key), property));
+				result.put(key, createDbRefFor(dbObject.get(key), property));
 			}
 			return result;
 		}
 
-		return createReferenceFor(source, property);
+		return createDbRefFor(source, property);
 	}
 
 	/**
@@ -682,17 +605,12 @@ public class QueryMapper {
 		return Collections.singletonMap(key, value).entrySet().iterator().next();
 	}
 
-	private Object createReferenceFor(Object source, MongoPersistentProperty property) {
+	private DBRef createDbRefFor(Object source, MongoPersistentProperty property) {
 
 		if (source instanceof DBRef) {
 			return (DBRef) source;
 		}
 
-		if (property != null && (property.isDocumentReference()
-				|| (!property.isDbReference() && property.findAnnotation(Reference.class) != null))) {
-			return converter.toDocumentPointer(source, property).getPointer();
-		}
-
 		return converter.toDBRef(source, property);
 	}
 
@@ -959,11 +877,6 @@ public class QueryMapper {
 			return null;
 		}
 
-		@Nullable
-		MongoPersistentEntity<?> getEntity() {
-			return null;
-		}
-
 		/**
 		 * Returns whether the field represents an association.
 		 *
@@ -1009,7 +922,6 @@ public class QueryMapper {
 		public TypeInformation<?> getTypeHint() {
 			return ClassTypeInformation.OBJECT;
 		}
-
 	}
 
 	/**
@@ -1116,12 +1028,6 @@ public class QueryMapper {
 			return property == null ? null : mappingContext.getPersistentEntity(property);
 		}
 
-		@Nullable
-		@Override
-		public MongoPersistentEntity<?> getEntity() {
-			return entity;
-		}
-
 		/*
 		 * (non-Javadoc)
 		 * @see org.springframework.data.mongodb.core.convert.QueryMapper.Field#isAssociation()

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/convert/ReferenceLoader.java

@@ -1,130 +0,0 @@
-/*
- * Copyright 2021 the original author or authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      https://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.springframework.data.mongodb.core.convert;
-
-import java.util.Collections;
-import java.util.Iterator;
-
-import org.bson.Document;
-import org.bson.conversions.Bson;
-import org.springframework.data.mongodb.core.convert.ReferenceResolver.ReferenceCollection;
-import org.springframework.lang.Nullable;
-
-import com.mongodb.client.MongoCollection;
-
-/**
- * The {@link ReferenceLoader} obtains raw {@link Document documents} for linked entities via a
- * {@link ReferenceLoader.DocumentReferenceQuery}.
- *
- * @author Christoph Strobl
- * @since 3.3
- */
-public interface ReferenceLoader {
-
-	/**
-	 * Obtain a single {@link Document} matching the given {@literal referenceQuery} in the {@literal context}.
-	 *
-	 * @param referenceQuery must not be {@literal null}.
-	 * @param context must not be {@literal null}.
-	 * @return the matching {@link Document} or {@literal null} if none found.
-	 */
-	@Nullable
-	default Document fetchOne(DocumentReferenceQuery referenceQuery, ReferenceCollection context) {
-
-		Iterator<Document> it = fetchMany(referenceQuery, context).iterator();
-		return it.hasNext() ? it.next() : null;
-	}
-
-	/**
-	 * Obtain multiple {@link Document} matching the given {@literal referenceQuery} in the {@literal context}.
-	 *
-	 * @param referenceQuery must not be {@literal null}.
-	 * @param context must not be {@literal null}.
-	 * @return the matching {@link Document} or {@literal null} if none found.
-	 */
-	Iterable<Document> fetchMany(DocumentReferenceQuery referenceQuery, ReferenceCollection context);
-
-	/**
-	 * The {@link DocumentReferenceQuery} defines the criteria by which {@link Document documents} should be matched
-	 * applying potentially given order criteria.
-	 */
-	interface DocumentReferenceQuery {
-
-		/**
-		 * Get the query to obtain matching {@link Document documents}.
-		 *
-		 * @return never {@literal null}.
-		 */
-		Bson getQuery();
-
-		/**
-		 * Get the sort criteria for ordering results.
-		 *
-		 * @return an empty {@link Document} by default. Never {@literal null}.
-		 */
-		default Bson getSort() {
-			return new Document();
-		}
-
-		default Iterable<Document> apply(MongoCollection<Document> collection) {
-			return restoreOrder(collection.find(getQuery()).sort(getSort()));
-		}
-
-		/**
-		 * Restore the order of fetched documents.
-		 *
-		 * @param documents must not be {@literal null}.
-		 * @return never {@literal null}.
-		 */
-		default Iterable<Document> restoreOrder(Iterable<Document> documents) {
-			return documents;
-		}
-
-		static DocumentReferenceQuery forSingleDocument(Bson bson) {
-
-			return new DocumentReferenceQuery() {
-
-				@Override
-				public Bson getQuery() {
-					return bson;
-				}
-
-				@Override
-				public Iterable<Document> apply(MongoCollection<Document> collection) {
-
-					Document result = collection.find(getQuery()).sort(getSort()).limit(1).first();
-					return result != null ? Collections.singleton(result) : Collections.emptyList();
-				}
-			};
-		}
-
-		static DocumentReferenceQuery forManyDocuments(Bson bson) {
-
-			return new DocumentReferenceQuery() {
-
-				@Override
-				public Bson getQuery() {
-					return bson;
-				}
-
-				@Override
-				public Iterable<Document> apply(MongoCollection<Document> collection) {
-					return collection.find(getQuery()).sort(getSort());
-				}
-			};
-		}
-	}
-}

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/convert/ReferenceLookupDelegate.java

@@ -1,451 +0,0 @@
-/*
- * Copyright 2021 the original author or authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      https://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.springframework.data.mongodb.core.convert;
-
-import java.lang.annotation.Annotation;
-import java.util.ArrayList;
-import java.util.Collection;
-import java.util.Collections;
-import java.util.LinkedHashMap;
-import java.util.List;
-import java.util.Map;
-import java.util.Map.Entry;
-import java.util.Optional;
-import java.util.Set;
-import java.util.function.Supplier;
-import java.util.stream.Collectors;
-
-import org.bson.Document;
-import org.bson.conversions.Bson;
-import org.springframework.data.mapping.context.MappingContext;
-import org.springframework.data.mapping.model.SpELContext;
-import org.springframework.data.mongodb.core.convert.ReferenceLoader.DocumentReferenceQuery;
-import org.springframework.data.mongodb.core.convert.ReferenceResolver.MongoEntityReader;
-import org.springframework.data.mongodb.core.convert.ReferenceResolver.ReferenceCollection;
-import org.springframework.data.mongodb.core.mapping.DocumentReference;
-import org.springframework.data.mongodb.core.mapping.MongoPersistentEntity;
-import org.springframework.data.mongodb.core.mapping.MongoPersistentProperty;
-import org.springframework.data.mongodb.util.BsonUtils;
-import org.springframework.data.mongodb.util.json.ParameterBindingContext;
-import org.springframework.data.mongodb.util.json.ParameterBindingDocumentCodec;
-import org.springframework.data.mongodb.util.json.ValueProvider;
-import org.springframework.data.util.Streamable;
-import org.springframework.expression.EvaluationContext;
-import org.springframework.lang.Nullable;
-import org.springframework.util.Assert;
-import org.springframework.util.StringUtils;
-
-import com.mongodb.DBRef;
-import com.mongodb.client.MongoCollection;
-
-/**
- * A common delegate for {@link ReferenceResolver} implementations to resolve a reference to one/many target documents
- * that are converted to entities.
- *
- * @author Christoph Strobl
- * @author Mark Paluch
- * @since 3.3
- */
-public final class ReferenceLookupDelegate {
-
-	private final MappingContext<? extends MongoPersistentEntity<?>, MongoPersistentProperty> mappingContext;
-	private final SpELContext spELContext;
-	private final ParameterBindingDocumentCodec codec;
-
-	/**
-	 * Create a new {@link ReferenceLookupDelegate}.
-	 *
-	 * @param mappingContext must not be {@literal null}.
-	 * @param spELContext must not be {@literal null}.
-	 */
-	public ReferenceLookupDelegate(
-			MappingContext<? extends MongoPersistentEntity<?>, MongoPersistentProperty> mappingContext,
-			SpELContext spELContext) {
-
-		Assert.notNull(mappingContext, "MappingContext must not be null");
-		Assert.notNull(spELContext, "SpELContext must not be null");
-
-		this.mappingContext = mappingContext;
-		this.spELContext = spELContext;
-		this.codec = new ParameterBindingDocumentCodec();
-	}
-
-	/**
-	 * Read the reference expressed by the given property.
-	 *
-	 * @param property the reference defining property. Must not be {@literal null}. THe
-	 * @param value the source value identifying to the referenced entity. Must not be {@literal null}.
-	 * @param lookupFunction to execute a lookup query. Must not be {@literal null}.
-	 * @param entityReader the callback to convert raw source values into actual domain types. Must not be
-	 *          {@literal null}.
-	 * @return can be {@literal null}.
-	 */
-	@Nullable
-	public Object readReference(MongoPersistentProperty property, Object value, LookupFunction lookupFunction,
-			MongoEntityReader entityReader) {
-
-		DocumentReferenceQuery filter = computeFilter(property, value, spELContext);
-		ReferenceCollection referenceCollection = computeReferenceContext(property, value, spELContext);
-
-		Iterable<Document> result = lookupFunction.apply(filter, referenceCollection);
-
-		if (property.isCollectionLike()) {
-			return entityReader.read(result, property.getTypeInformation());
-		}
-
-		if (!result.iterator().hasNext()) {
-			return null;
-		}
-
-		Object resultValue = result.iterator().next();
-		return resultValue != null ? entityReader.read(resultValue, property.getTypeInformation()) : null;
-	}
-
-	private ReferenceCollection computeReferenceContext(MongoPersistentProperty property, Object value,
-			SpELContext spELContext) {
-
-		// Use the first value as a reference for others in case of collection like
-		if (value instanceof Iterable) {
-			value = ((Iterable<?>) value).iterator().next();
-		}
-
-		// handle DBRef value
-		if (value instanceof DBRef) {
-			return ReferenceCollection.fromDBRef((DBRef) value);
-		}
-
-		String collection = mappingContext.getRequiredPersistentEntity(property.getAssociationTargetType()).getCollection();
-
-		if (value instanceof Document) {
-
-			Document documentPointer = (Document) value;
-
-			if (property.isDocumentReference()) {
-
-				ParameterBindingContext bindingContext = bindingContext(property, value, spELContext);
-				DocumentReference documentReference = property.getDocumentReference();
-
-				String targetDatabase = parseValueOrGet(documentReference.db(), bindingContext,
-						() -> documentPointer.get("db", String.class));
-				String targetCollection = parseValueOrGet(documentReference.collection(), bindingContext,
-						() -> documentPointer.get("collection", collection));
-				return new ReferenceCollection(targetDatabase, targetCollection);
-			}
-
-			return new ReferenceCollection(documentPointer.getString("db"), documentPointer.get("collection", collection));
-		}
-
-		if (property.isDocumentReference()) {
-
-			ParameterBindingContext bindingContext = bindingContext(property, value, spELContext);
-			DocumentReference documentReference = property.getDocumentReference();
-
-			String targetDatabase = parseValueOrGet(documentReference.db(), bindingContext, () -> null);
-			String targetCollection = parseValueOrGet(documentReference.collection(), bindingContext, () -> collection);
-
-			return new ReferenceCollection(targetDatabase, targetCollection);
-		}
-
-		return new ReferenceCollection(null, collection);
-	}
-
-	/**
-	 * Use the given {@link ParameterBindingContext} to compute potential expressions against the value.
-	 *
-	 * @param value must not be {@literal null}.
-	 * @param bindingContext must not be {@literal null}.
-	 * @param defaultValue
-	 * @param <T>
-	 * @return can be {@literal null}.
-	 */
-	@Nullable
-	@SuppressWarnings("unchecked")
-	private <T> T parseValueOrGet(String value, ParameterBindingContext bindingContext, Supplier<T> defaultValue) {
-
-		if (!StringUtils.hasText(value)) {
-			return defaultValue.get();
-		}
-
-		// parameter binding requires a document, since we do not have one, construct it.
-		if (!BsonUtils.isJsonDocument(value) && value.contains("?#{")) {
-			String s = "{ 'target-value' : " + value + "}";
-			T evaluated = (T) codec.decode(s, bindingContext).get("target-value");
-			return evaluated != null ? evaluated : defaultValue.get();
-		}
-
-		if (BsonUtils.isJsonDocument(value)) {
-			return (T) codec.decode(value, bindingContext);
-		}
-
-		T evaluated = (T) bindingContext.evaluateExpression(value);
-		return evaluated != null ? evaluated : defaultValue.get();
-	}
-
-	ParameterBindingContext bindingContext(MongoPersistentProperty property, Object source, SpELContext spELContext) {
-
-		return new ParameterBindingContext(valueProviderFor(source), spELContext.getParser(),
-				() -> evaluationContextFor(property, source, spELContext));
-	}
-
-	ValueProvider valueProviderFor(Object source) {
-
-		return (index) -> {
-			if (source instanceof Document) {
-				return Streamable.of(((Document) source).values()).toList().get(index);
-			}
-			return source;
-		};
-	}
-
-	EvaluationContext evaluationContextFor(MongoPersistentProperty property, Object source, SpELContext spELContext) {
-
-		EvaluationContext ctx = spELContext.getEvaluationContext(source);
-		ctx.setVariable("target", source);
-		ctx.setVariable(property.getName(), source);
-
-		return ctx;
-	}
-
-	/**
-	 * Compute the query to retrieve linked documents.
-	 *
-	 * @param property must not be {@literal null}.
-	 * @param value must not be {@literal null}.
-	 * @param spELContext must not be {@literal null}.
-	 * @return never {@literal null}.
-	 */
-	@SuppressWarnings("unchecked")
-	DocumentReferenceQuery computeFilter(MongoPersistentProperty property, Object value, SpELContext spELContext) {
-
-		DocumentReference documentReference = property.isDocumentReference() ? property.getDocumentReference()
-				: ReferenceEmulatingDocumentReference.INSTANCE;
-
-		String lookup = documentReference.lookup();
-
-		Document sort = parseValueOrGet(documentReference.sort(), bindingContext(property, value, spELContext),
-				() -> new Document());
-
-		if (property.isCollectionLike() && value instanceof Collection) {
-
-			List<Document> ors = new ArrayList<>();
-			for (Object entry : (Collection<Object>) value) {
-
-				Document decoded = codec.decode(lookup, bindingContext(property, entry, spELContext));
-				ors.add(decoded);
-			}
-
-			return new ListDocumentReferenceQuery(new Document("$or", ors), sort);
-		}
-
-		if (property.isMap() && value instanceof Map) {
-
-			Map<Object, Document> filterMap = new LinkedHashMap<>();
-
-			for (Entry<Object, Object> entry : ((Map<Object, Object>) value).entrySet()) {
-
-				Document decoded = codec.decode(lookup, bindingContext(property, entry.getValue(), spELContext));
-				filterMap.put(entry.getKey(), decoded);
-			}
-
-			return new MapDocumentReferenceQuery(new Document("$or", filterMap.values()), sort, filterMap);
-		}
-
-		return new SingleDocumentReferenceQuery(codec.decode(lookup, bindingContext(property, value, spELContext)), sort);
-	}
-
-	enum ReferenceEmulatingDocumentReference implements DocumentReference {
-
-		INSTANCE;
-
-		@Override
-		public Class<? extends Annotation> annotationType() {
-			return DocumentReference.class;
-		}
-
-		@Override
-		public String db() {
-			return "";
-		}
-
-		@Override
-		public String collection() {
-			return "";
-		}
-
-		@Override
-		public String lookup() {
-			return "{ '_id' : ?#{#target} }";
-		}
-
-		@Override
-		public String sort() {
-			return "";
-		}
-
-		@Override
-		public boolean lazy() {
-			return false;
-		}
-	}
-
-	/**
-	 * {@link DocumentReferenceQuery} implementation fetching a single {@link Document}.
-	 */
-	static class SingleDocumentReferenceQuery implements DocumentReferenceQuery {
-
-		private final Document query;
-		private final Document sort;
-
-		public SingleDocumentReferenceQuery(Document query, Document sort) {
-
-			this.query = query;
-			this.sort = sort;
-		}
-
-		@Override
-		public Bson getQuery() {
-			return query;
-		}
-
-		@Override
-		public Document getSort() {
-			return sort;
-		}
-
-		@Override
-		public Iterable<Document> apply(MongoCollection<Document> collection) {
-
-			Document result = collection.find(getQuery()).sort(getSort()).limit(1).first();
-			return result != null ? Collections.singleton(result) : Collections.emptyList();
-		}
-	}
-
-	/**
-	 * {@link DocumentReferenceQuery} implementation to retrieve linked {@link Document documents} stored inside a
-	 * {@link Map} structure. Restores the original map order by matching individual query documents against the actual
-	 * values.
-	 */
-	static class MapDocumentReferenceQuery implements DocumentReferenceQuery {
-
-		private final Document query;
-		private final Document sort;
-		private final Map<Object, Document> filterOrderMap;
-
-		public MapDocumentReferenceQuery(Document query, Document sort, Map<Object, Document> filterOrderMap) {
-
-			this.query = query;
-			this.sort = sort;
-			this.filterOrderMap = filterOrderMap;
-		}
-
-		@Override
-		public Bson getQuery() {
-			return query;
-		}
-
-		@Override
-		public Bson getSort() {
-			return sort;
-		}
-
-		@Override
-		public Iterable<Document> restoreOrder(Iterable<Document> documents) {
-
-			Map<String, Object> targetMap = new LinkedHashMap<>();
-			List<Document> collected = documents instanceof List ? (List<Document>) documents
-					: Streamable.of(documents).toList();
-
-			for (Entry<Object, Document> filterMapping : filterOrderMap.entrySet()) {
-
-				Optional<Document> first = collected.stream()
-						.filter(it -> it.entrySet().containsAll(filterMapping.getValue().entrySet())).findFirst();
-
-				targetMap.put(filterMapping.getKey().toString(), first.orElse(null));
-			}
-			return Collections.singleton(new Document(targetMap));
-		}
-	}
-
-	/**
-	 * {@link DocumentReferenceQuery} implementation to retrieve linked {@link Document documents} stored inside a
-	 * {@link Collection} like structure. Restores the original order by matching individual query documents against the
-	 * actual values.
-	 */
-	static class ListDocumentReferenceQuery implements DocumentReferenceQuery {
-
-		private final Document query;
-		private final Document sort;
-
-		public ListDocumentReferenceQuery(Document query, Document sort) {
-
-			this.query = query;
-			this.sort = sort;
-		}
-
-		@Override
-		public Iterable<Document> restoreOrder(Iterable<Document> documents) {
-
-			List<Document> target = documents instanceof List ? (List<Document>) documents
-					: Streamable.of(documents).toList();
-
-			if (!sort.isEmpty() || !query.containsKey("$or")) {
-				return target;
-			}
-
-			List<Document> ors = query.get("$or", List.class);
-			return target.stream().sorted((o1, o2) -> compareAgainstReferenceIndex(ors, o1, o2)).collect(Collectors.toList());
-		}
-
-		public Document getQuery() {
-			return query;
-		}
-
-		@Override
-		public Document getSort() {
-			return sort;
-		}
-
-		int compareAgainstReferenceIndex(List<Document> referenceList, Document document1, Document document2) {
-
-			for (Document document : referenceList) {
-
-				Set<Entry<String, Object>> entries = document.entrySet();
-				if (document1.entrySet().containsAll(entries)) {
-					return -1;
-				}
-				if (document2.entrySet().containsAll(entries)) {
-					return 1;
-				}
-			}
-			return referenceList.size();
-		}
-	}
-
-	/**
-	 * The function that can execute a given {@link DocumentReferenceQuery} within the {@link ReferenceCollection} to
-	 * obtain raw results.
-	 */
-	@FunctionalInterface
-	interface LookupFunction {
-
-		/**
-		 * @param referenceQuery never {@literal null}.
-		 * @param referenceCollection never {@literal null}.
-		 * @return never {@literal null}.
-		 */
-		Iterable<Document> apply(DocumentReferenceQuery referenceQuery, ReferenceCollection referenceCollection);
-	}
-}

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/convert/ReferenceResolver.java

@@ -1,119 +0,0 @@
-/*
- * Copyright 2021 the original author or authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      https://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.springframework.data.mongodb.core.convert;
-
-import org.springframework.data.mapping.PersistentProperty;
-import org.springframework.data.mongodb.MongoDatabaseFactory;
-import org.springframework.data.mongodb.core.mapping.MongoPersistentProperty;
-import org.springframework.data.util.TypeInformation;
-import org.springframework.lang.Nullable;
-import org.springframework.util.Assert;
-
-import com.mongodb.DBRef;
-
-/**
- * The {@link ReferenceResolver} allows to load and convert linked entities.
- *
- * @author Christoph Strobl
- * @since 3.3
- */
-@FunctionalInterface
-public interface ReferenceResolver {
-
-	/**
-	 * Resolve the association defined via the given property from a given source value. May return a
-	 * {@link LazyLoadingProxy proxy instance} in case of a lazy loading association. The resolved value is assignable to
-	 * {@link PersistentProperty#getType()}.
-	 *
-	 * @param property the association defining property.
-	 * @param source the association source value.
-	 * @param referenceLookupDelegate the lookup executing component.
-	 * @param entityReader conversion function capable of constructing entities from raw source.
-	 * @return can be {@literal null}.
-	 */
-	@Nullable
-	Object resolveReference(MongoPersistentProperty property, Object source,
-			ReferenceLookupDelegate referenceLookupDelegate, MongoEntityReader entityReader);
-
-	/**
-	 * {@link ReferenceCollection} is a value object that contains information about the target database and collection
-	 * name of an association.
-	 */
-	class ReferenceCollection {
-
-		@Nullable //
-		private final String database;
-		private final String collection;
-
-		/**
-		 * @param database can be {@literal null} to indicate the configured default
-		 *          {@link MongoDatabaseFactory#getMongoDatabase() database} should be used.
-		 * @param collection the target collection name. Must not be {@literal null}.
-		 */
-		public ReferenceCollection(@Nullable String database, String collection) {
-
-			Assert.hasText(collection, "Collection must not be empty or null!");
-
-			this.database = database;
-			this.collection = collection;
-		}
-
-		/**
-		 * Create a new instance of {@link ReferenceCollection} from the given {@link DBRef}.
-		 *
-		 * @param dbRef must not be {@literal null}.
-		 * @return new instance of {@link ReferenceCollection}.
-		 */
-		public static ReferenceCollection fromDBRef(DBRef dbRef) {
-			return new ReferenceCollection(dbRef.getDatabaseName(), dbRef.getCollectionName());
-		}
-
-		/**
-		 * Get the target collection name.
-		 *
-		 * @return never {@literal null}.
-		 */
-		public String getCollection() {
-			return collection;
-		}
-
-		/**
-		 * Get the target database name. If {@literal null} the default database should be used.
-		 *
-		 * @return can be {@literal null}.
-		 */
-		@Nullable
-		public String getDatabase() {
-			return database;
-		}
-	}
-
-	/**
-	 * Domain type conversion callback interface that allows to read the {@code source} object into a mapped object.
-	 */
-	@FunctionalInterface
-	interface MongoEntityReader {
-
-		/**
-		 * Read values from the given source into an object defined via the given {@link TypeInformation}.
-		 *
-		 * @param source never {@literal null}.
-		 * @param typeInformation information about the desired target type.
-		 * @return never {@literal null}.
-		 */
-		Object read(Object source, TypeInformation<?> typeInformation);
-	}
-}

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/convert/UpdateMapper.java

@@ -132,11 +132,6 @@ public class UpdateMapper extends QueryMapper {
 	 */
 	@Override
 	protected Object delegateConvertToMongoType(Object source, @Nullable MongoPersistentEntity<?> entity) {
-
-		if(entity != null && entity.isUnwrapped()) {
-			return converter.convertToMongoType(source, entity);
-		}
-
 		return converter.convertToMongoType(source,
 				entity == null ? ClassTypeInformation.OBJECT : getTypeHintForEntity(source, entity));
 	}

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/geo/GeoJsonModule.java

@@ -24,7 +24,7 @@ import org.springframework.data.geo.Point;
 import org.springframework.lang.Nullable;
 
 import com.fasterxml.jackson.core.JsonParser;
-import com.fasterxml.jackson.core.Version;
+import com.fasterxml.jackson.core.JsonProcessingException;
 import com.fasterxml.jackson.databind.DeserializationContext;
 import com.fasterxml.jackson.databind.JsonDeserializer;
 import com.fasterxml.jackson.databind.JsonNode;
@@ -34,10 +34,7 @@ import com.fasterxml.jackson.databind.module.SimpleModule;
 import com.fasterxml.jackson.databind.node.ArrayNode;
 
 /**
- * A Jackson {@link Module} to register custom {@link JsonDeserializer}s for GeoJSON types.
- * <p />
- * Use {@link #geoJsonModule()} to obtain a {@link Module} containing both {@link JsonSerializer serializers} and
- * {@link JsonDeserializer deserializers}.
+ * A Jackson {@link Module} to register custom {@link JsonSerializer} and {@link JsonDeserializer}s for GeoJSON types.
  *
  * @author Christoph Strobl
  * @author Oliver Gierke
@@ -50,87 +47,12 @@ public class GeoJsonModule extends SimpleModule {
 
 	public GeoJsonModule() {
 
-		registerDeserializersIn(this);
-		// TODO: add serializers as of next major version (4.0).
-	}
-
-	/**
-	 * Obtain a {@link Module} containing {@link JsonDeserializer deserializers} for the following {@link GeoJson} types:
-	 * <ul>
-	 * <li>{@link GeoJsonPoint}</li>
-	 * <li>{@link GeoJsonMultiPoint}</li>
-	 * <li>{@link GeoJsonLineString}</li>
-	 * <li>{@link GeoJsonMultiLineString}</li>
-	 * <li>{@link GeoJsonPolygon}</li>
-	 * <li>{@link GeoJsonMultiPolygon}</li>
-	 * </ul>
-	 *
-	 * @return a {@link Module} containing {@link JsonDeserializer deserializers} for {@link GeoJson} types.
-	 * @since 3.2
-	 */
-	public static Module deserializers() {
-
-		SimpleModule module = new SimpleModule("Spring Data MongoDB GeoJson - Deserializers",
-				new Version(3, 2, 0, null, "org.springframework.data", "spring-data-mongodb-geojson"));
-		registerDeserializersIn(module);
-		return module;
-	}
-
-	/**
-	 * Obtain a {@link Module} containing {@link JsonSerializer serializers} for the following {@link GeoJson} types:
-	 * <ul>
-	 * <li>{@link GeoJsonPoint}</li>
-	 * <li>{@link GeoJsonMultiPoint}</li>
-	 * <li>{@link GeoJsonLineString}</li>
-	 * <li>{@link GeoJsonMultiLineString}</li>
-	 * <li>{@link GeoJsonPolygon}</li>
-	 * <li>{@link GeoJsonMultiPolygon}</li>
-	 * </ul>
-	 *
-	 * @return a {@link Module} containing {@link JsonSerializer serializers} for {@link GeoJson} types.
-	 * @since 3.2
-	 */
-	public static Module serializers() {
-
-		SimpleModule module = new SimpleModule("Spring Data MongoDB GeoJson - Serializers",
-				new Version(3, 2, 0, null, "org.springframework.data", "spring-data-mongodb-geojson"));
-		GeoJsonSerializersModule.registerSerializersIn(module);
-		return module;
-	}
-
-	/**
-	 * Obtain a {@link Module} containing {@link JsonSerializer serializers} and {@link JsonDeserializer deserializers}
-	 * for the following {@link GeoJson} types:
-	 * <ul>
-	 * <li>{@link GeoJsonPoint}</li>
-	 * <li>{@link GeoJsonMultiPoint}</li>
-	 * <li>{@link GeoJsonLineString}</li>
-	 * <li>{@link GeoJsonMultiLineString}</li>
-	 * <li>{@link GeoJsonPolygon}</li>
-	 * <li>{@link GeoJsonMultiPolygon}</li>
-	 * </ul>
-	 *
-	 * @return a {@link Module} containing {@link JsonSerializer serializers} and {@link JsonDeserializer deserializers}
-	 *         for {@link GeoJson} types.
-	 * @since 3.2
-	 */
-	public static Module geoJsonModule() {
-
-		SimpleModule module = new SimpleModule("Spring Data MongoDB GeoJson",
-				new Version(3, 2, 0, null, "org.springframework.data", "spring-data-mongodb-geojson"));
-		GeoJsonSerializersModule.registerSerializersIn(module);
-		registerDeserializersIn(module);
-		return module;
-	}
-
-	private static void registerDeserializersIn(SimpleModule module) {
-
-		module.addDeserializer(GeoJsonPoint.class, new GeoJsonPointDeserializer());
-		module.addDeserializer(GeoJsonMultiPoint.class, new GeoJsonMultiPointDeserializer());
-		module.addDeserializer(GeoJsonLineString.class, new GeoJsonLineStringDeserializer());
-		module.addDeserializer(GeoJsonMultiLineString.class, new GeoJsonMultiLineStringDeserializer());
-		module.addDeserializer(GeoJsonPolygon.class, new GeoJsonPolygonDeserializer());
-		module.addDeserializer(GeoJsonMultiPolygon.class, new GeoJsonMultiPolygonDeserializer());
+		addDeserializer(GeoJsonPoint.class, new GeoJsonPointDeserializer());
+		addDeserializer(GeoJsonMultiPoint.class, new GeoJsonMultiPointDeserializer());
+		addDeserializer(GeoJsonLineString.class, new GeoJsonLineStringDeserializer());
+		addDeserializer(GeoJsonMultiLineString.class, new GeoJsonMultiLineStringDeserializer());
+		addDeserializer(GeoJsonPolygon.class, new GeoJsonPolygonDeserializer());
+		addDeserializer(GeoJsonMultiPolygon.class, new GeoJsonMultiPolygonDeserializer());
 	}
 
 	/**
@@ -145,7 +67,8 @@ public class GeoJsonModule extends SimpleModule {
 		 */
 		@Nullable
 		@Override
-		public T deserialize(@Nullable JsonParser jp, @Nullable DeserializationContext ctxt) throws IOException {
+		public T deserialize(@Nullable JsonParser jp, @Nullable DeserializationContext ctxt)
+				throws IOException, JsonProcessingException {
 
 			JsonNode node = jp.readValueAsTree();
 			JsonNode coordinates = node.get("coordinates");
@@ -211,7 +134,7 @@ public class GeoJsonModule extends SimpleModule {
 				return Collections.emptyList();
 			}
 
-			List<Point> points = new ArrayList<>(node.size());
+			List<Point> points = new ArrayList<Point>(node.size());
 
 			for (JsonNode coordinatePair : node) {
 				if (coordinatePair.isArray()) {
@@ -222,7 +145,7 @@ public class GeoJsonModule extends SimpleModule {
 		}
 
 		protected GeoJsonLineString toLineString(ArrayNode node) {
-			return new GeoJsonLineString(toPoints(node));
+			return new GeoJsonLineString(toPoints((ArrayNode) node));
 		}
 	}
 
@@ -336,7 +259,7 @@ public class GeoJsonModule extends SimpleModule {
 		@Override
 		protected GeoJsonMultiLineString doDeserialize(ArrayNode coordinates) {
 
-			List<GeoJsonLineString> lines = new ArrayList<>(coordinates.size());
+			List<GeoJsonLineString> lines = new ArrayList<GeoJsonLineString>(coordinates.size());
 
 			for (JsonNode lineString : coordinates) {
 				if (lineString.isArray()) {
@@ -413,7 +336,7 @@ public class GeoJsonModule extends SimpleModule {
 		@Override
 		protected GeoJsonMultiPolygon doDeserialize(ArrayNode coordinates) {
 
-			List<GeoJsonPolygon> polygones = new ArrayList<>(coordinates.size());
+			List<GeoJsonPolygon> polygones = new ArrayList<GeoJsonPolygon>(coordinates.size());
 
 			for (JsonNode polygon : coordinates) {
 				for (JsonNode ring : polygon) {

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/geo/GeoJsonSerializersModule.java

@@ -1,313 +0,0 @@
-/*
- * Copyright 2021 the original author or authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      https://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.springframework.data.mongodb.core.geo;
-
-import java.io.IOException;
-
-import org.springframework.data.geo.Point;
-
-import com.fasterxml.jackson.core.JsonGenerator;
-import com.fasterxml.jackson.databind.JsonSerializer;
-import com.fasterxml.jackson.databind.Module;
-import com.fasterxml.jackson.databind.SerializerProvider;
-import com.fasterxml.jackson.databind.module.SimpleModule;
-
-/**
- * A Jackson {@link Module} to register custom {@link JsonSerializer}s for GeoJSON types.
- *
- * @author Bjorn Harvold
- * @author Christoph Strobl
- * @since 3.2
- */
-class GeoJsonSerializersModule extends SimpleModule {
-
-	private static final long serialVersionUID = 1340494654898895610L;
-
-	GeoJsonSerializersModule() {
-		registerSerializersIn(this);
-	}
-
-
-	static void registerSerializersIn(SimpleModule module) {
-
-		module.addSerializer(GeoJsonPoint.class, new GeoJsonPointSerializer());
-		module.addSerializer(GeoJsonMultiPoint.class, new GeoJsonMultiPointSerializer());
-		module.addSerializer(GeoJsonLineString.class, new GeoJsonLineStringSerializer());
-		module.addSerializer(GeoJsonMultiLineString.class, new GeoJsonMultiLineStringSerializer());
-		module.addSerializer(GeoJsonPolygon.class, new GeoJsonPolygonSerializer());
-		module.addSerializer(GeoJsonMultiPolygon.class, new GeoJsonMultiPolygonSerializer());
-	}
-
-	/**
-	 * @param <T>
-	 * @author Christoph Strobl
-	 */
-	private static abstract class GeoJsonSerializer<T extends GeoJson<? extends Iterable>> extends JsonSerializer<T> {
-
-		/*
-		 * (non-Javadoc)
-		 * @see com.fasterxml.jackson.databind.JsonSerializer#serialize(java.lang.Object, com.fasterxml.jackson.core.JsonGenerator, com.fasterxml.jackson.databind.SerializerProvider)
-		 */
-		@Override
-		public void serialize(T shape, JsonGenerator jsonGenerator, SerializerProvider serializers) throws IOException {
-
-			jsonGenerator.writeStartObject();
-			jsonGenerator.writeStringField("type", shape.getType());
-			jsonGenerator.writeArrayFieldStart("coordinates");
-
-			doSerialize(shape, jsonGenerator);
-
-			jsonGenerator.writeEndArray();
-			jsonGenerator.writeEndObject();
-		}
-
-		/**
-		 * Perform the actual serialization given the {@literal shape} as {@link GeoJson}.
-		 *
-		 * @param shape
-		 * @param jsonGenerator
-		 * @return
-		 */
-		protected abstract void doSerialize(T shape, JsonGenerator jsonGenerator) throws IOException;
-
-		/**
-		 * Write a {@link Point} as array. <br />
-		 * {@code [10.0, 20.0]}
-		 *
-		 * @param point
-		 * @param jsonGenerator
-		 * @throws IOException
-		 */
-		protected void writePoint(Point point, JsonGenerator jsonGenerator) throws IOException {
-
-			jsonGenerator.writeStartArray();
-			writeRawCoordinates(point, jsonGenerator);
-			jsonGenerator.writeEndArray();
-		}
-
-		/**
-		 * Write the {@link Point} coordinates. <br />
-		 * {@code 10.0, 20.0}
-		 *
-		 * @param point
-		 * @param jsonGenerator
-		 * @throws IOException
-		 */
-		protected void writeRawCoordinates(Point point, JsonGenerator jsonGenerator) throws IOException {
-
-			jsonGenerator.writeNumber(point.getX());
-			jsonGenerator.writeNumber(point.getY());
-		}
-
-		/**
-		 * Write an {@link Iterable} of {@link Point} as array. <br />
-		 * {@code [ [10.0, 20.0], [30.0, 40.0], [50.0, 60.0] ]}
-		 *
-		 * @param points
-		 * @param jsonGenerator
-		 * @throws IOException
-		 */
-		protected void writeLine(Iterable<Point> points, JsonGenerator jsonGenerator) throws IOException {
-
-			jsonGenerator.writeStartArray();
-			writeRawLine(points, jsonGenerator);
-			jsonGenerator.writeEndArray();
-		}
-
-		/**
-		 * Write an {@link Iterable} of {@link Point}. <br />
-		 * {@code [10.0, 20.0], [30.0, 40.0], [50.0, 60.0]}
-		 *
-		 * @param points
-		 * @param jsonGenerator
-		 * @throws IOException
-		 */
-		protected void writeRawLine(Iterable<Point> points, JsonGenerator jsonGenerator) throws IOException {
-
-			for (Point point : points) {
-				writePoint(point, jsonGenerator);
-			}
-		}
-	}
-
-	/**
-	 * {@link JsonSerializer} converting {@link GeoJsonPoint} to:
-	 *
-	 * <pre>
-	 * <code>
-	 * { "type": "Point", "coordinates": [10.0, 20.0] }
-	 * </code>
-	 * </pre>
-	 *
-	 * @author Bjorn Harvold
-	 * @author Christoph Strobl
-	 * @since 3.2
-	 */
-	static class GeoJsonPointSerializer extends GeoJsonSerializer<GeoJsonPoint> {
-
-		@Override
-		protected void doSerialize(GeoJsonPoint value, JsonGenerator jsonGenerator) throws IOException {
-			writeRawCoordinates(value, jsonGenerator);
-		}
-	}
-
-	/**
-	 * {@link JsonSerializer} converting {@link GeoJsonLineString} to:
-	 *
-	 * <pre>
-	 * <code>
-	 * {
-	 *   "type": "LineString",
-	 *   "coordinates": [
-	 *     [10.0, 20.0], [30.0, 40.0], [50.0, 60.0]
-	 *   ]
-	 * }
-	 * </code>
-	 * </pre>
-	 *
-	 * @author Bjorn Harvold
-	 * @author Christoph Strobl
-	 * @since 3.2
-	 */
-	static class GeoJsonLineStringSerializer extends GeoJsonSerializer<GeoJsonLineString> {
-
-		@Override
-		protected void doSerialize(GeoJsonLineString value, JsonGenerator jsonGenerator) throws IOException {
-			writeRawLine(value.getCoordinates(), jsonGenerator);
-		}
-	}
-
-	/**
-	 * {@link JsonSerializer} converting {@link GeoJsonMultiPoint} to:
-	 *
-	 * <pre>
-	 * <code>
-	 * {
-	 *   "type": "MultiPoint",
-	 *   "coordinates": [
-	 *     [10.0, 20.0], [30.0, 40.0], [50.0, 60.0]
-	 *   ]
-	 * }
-	 * </code>
-	 * </pre>
-	 *
-	 * @author Bjorn Harvold
-	 * @author Christoph Strobl
-	 * @since 3.2
-	 */
-	static class GeoJsonMultiPointSerializer extends GeoJsonSerializer<GeoJsonMultiPoint> {
-
-		@Override
-		protected void doSerialize(GeoJsonMultiPoint value, JsonGenerator jsonGenerator) throws IOException {
-			writeRawLine(value.getCoordinates(), jsonGenerator);
-		}
-	}
-
-	/**
-	 * {@link JsonSerializer} converting {@link GeoJsonMultiLineString} to:
-	 *
-	 * <pre>
-	 * <code>
-	 * {
-	 *   "type": "MultiLineString",
-	 *   "coordinates": [
-	 *     [ [10.0, 20.0], [30.0, 40.0] ],
-	 *     [ [50.0, 60.0] , [70.0, 80.0] ]
-	 *   ]
-	 * }
-	 * </code>
-	 * </pre>
-	 *
-	 * @author Bjorn Harvold
-	 * @author Christoph Strobl
-	 * @since 3.2
-	 */
-	static class GeoJsonMultiLineStringSerializer extends GeoJsonSerializer<GeoJsonMultiLineString> {
-
-		@Override
-		protected void doSerialize(GeoJsonMultiLineString value, JsonGenerator jsonGenerator) throws IOException {
-
-			for (GeoJsonLineString lineString : value.getCoordinates()) {
-				writeLine(lineString.getCoordinates(), jsonGenerator);
-			}
-		}
-	}
-
-	/**
-	 * {@link JsonSerializer} converting {@link GeoJsonPolygon} to:
-	 *
-	 * <pre>
-	 * <code>
-	 * {
-	 *   "type": "Polygon",
-	 *   "coordinates": [
-	 *     [ [100.0, 0.0], [101.0, 0.0], [101.0, 1.0], [100.0, 1.0], [100.0, 0.0] ]
-	 *   ]
-	 * }
-	 * </code>
-	 * </pre>
-	 *
-	 * @author Bjorn Harvold
-	 * @author Christoph Strobl
-	 * @since 3.2
-	 */
-	static class GeoJsonPolygonSerializer extends GeoJsonSerializer<GeoJsonPolygon> {
-
-		@Override
-		protected void doSerialize(GeoJsonPolygon value, JsonGenerator jsonGenerator) throws IOException {
-
-			for (GeoJsonLineString lineString : value.getCoordinates()) {
-				writeLine(lineString.getCoordinates(), jsonGenerator);
-			}
-		}
-	}
-
-	/**
-	 * {@link JsonSerializer} converting {@link GeoJsonMultiPolygon} to:
-	 *
-	 * <pre>
-	 * <code>
-	 * {
-	 *   "type": "MultiPolygon",
-	 *   "coordinates": [
-	 *     [[[102.0, 2.0], [103.0, 2.0], [103.0, 3.0], [102.0, 3.0], [102.0, 2.0]]],
-	 *     [[[100.0, 0.0], [101.0, 0.0], [101.0, 1.0], [100.0, 1.0], [100.0, 0.0]],
-	 *     [[100.2, 0.2], [100.8, 0.2], [100.8, 0.8], [100.2, 0.8], [100.2, 0.2]]]
-	 *   ]
-	 * }
-	 * </code>
-	 * </pre>
-	 *
-	 * @author Bjorn Harvold
-	 * @author Christoph Strobl
-	 * @since 3.2
-	 */
-	static class GeoJsonMultiPolygonSerializer extends GeoJsonSerializer<GeoJsonMultiPolygon> {
-
-		@Override
-		protected void doSerialize(GeoJsonMultiPolygon value, JsonGenerator jsonGenerator) throws IOException {
-
-			for (GeoJsonPolygon polygon : value.getCoordinates()) {
-
-				jsonGenerator.writeStartArray();
-				for (GeoJsonLineString lineString : polygon.getCoordinates()) {
-					writeLine(lineString.getCoordinates(), jsonGenerator);
-				}
-				jsonGenerator.writeEndArray();
-			}
-		}
-	}
-}

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/index/IndexField.java

@@ -29,17 +29,7 @@ import org.springframework.util.ObjectUtils;
 public final class IndexField {
 
 	enum Type {
-		GEO, TEXT, DEFAULT,
-
-		/**
-		 * @since 2.2
-		 */
-		HASH,
-
-		/**
-		 * @since 3.3
-		 */
-		WILDCARD;
+		GEO, TEXT, DEFAULT, HASH;
 	}
 
 	private final String key;
@@ -58,7 +48,7 @@ public final class IndexField {
 		if (Type.GEO.equals(type) || Type.TEXT.equals(type)) {
 			Assert.isNull(direction, "Geo/Text indexes must not have a direction!");
 		} else {
-			if (!(Type.HASH.equals(type) || Type.WILDCARD.equals(type))) {
+			if (!Type.HASH.equals(type)) {
 				Assert.notNull(direction, "Default indexes require a direction");
 			}
 		}
@@ -87,18 +77,6 @@ public final class IndexField {
 		return new IndexField(key, null, Type.HASH);
 	}
 
-	/**
-	 * Creates a {@literal wildcard} {@link IndexField} for the given key. The {@code key} must follow the
-	 * {@code fieldName.$**} notation.
-	 *
-	 * @param key must not be {@literal null} or empty.
-	 * @return new instance of {@link IndexField}.
-	 * @since 3.3
-	 */
-	static IndexField wildcard(String key) {
-		return new IndexField(key, null, Type.WILDCARD);
-	}
-
 	/**
 	 * Creates a geo {@link IndexField} for the given key.
 	 *
@@ -164,16 +142,6 @@ public final class IndexField {
 		return Type.HASH.equals(type);
 	}
 
-	/**
-	 * Returns whether the {@link IndexField} is contains a {@literal wildcard} expression.
-	 *
-	 * @return {@literal true} if {@link IndexField} contains a wildcard {@literal $**}.
-	 * @since 3.3
-	 */
-	public boolean isWildcard() {
-		return Type.WILDCARD.equals(type);
-	}
-
 	/*
 	 * (non-Javadoc)
 	 * @see java.lang.Object#equals(java.lang.Object)

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/index/IndexInfo.java

@@ -55,7 +55,6 @@ public class IndexInfo {
 	private @Nullable Duration expireAfter;
 	private @Nullable String partialFilterExpression;
 	private @Nullable Document collation;
-	private @Nullable Document wildcardProjection;
 
 	public IndexInfo(List<IndexField> indexFields, String name, boolean unique, boolean sparse, String language) {
 
@@ -100,8 +99,6 @@ public class IndexInfo {
 
 				if (ObjectUtils.nullSafeEquals("hashed", value)) {
 					indexFields.add(IndexField.hashed(key));
-				} else if (key.endsWith("$**")) {
-					indexFields.add(IndexField.wildcard(key));
 				} else {
 
 					Double keyValue = new Double(value.toString());
@@ -134,10 +131,6 @@ public class IndexInfo {
 			info.expireAfter = Duration.ofSeconds(NumberUtils.convertNumberToTargetClass(expireAfterSeconds, Long.class));
 		}
 
-		if (sourceDocument.containsKey("wildcardProjection")) {
-			info.wildcardProjection = sourceDocument.get("wildcardProjection", Document.class);
-		}
-
 		return info;
 	}
 
@@ -223,16 +216,6 @@ public class IndexInfo {
 		return Optional.ofNullable(collation);
 	}
 
-	/**
-	 * Get {@literal wildcardProjection} information.
-	 *
-	 * @return {@link Optional#empty() empty} if not set.
-	 * @since 3.3
-	 */
-	public Optional<Document> getWildcardProjection() {
-		return Optional.ofNullable(wildcardProjection);
-	}
-
 	/**
 	 * Get the duration after which documents within the index expire.
 	 *
@@ -251,14 +234,6 @@ public class IndexInfo {
 		return getIndexFields().stream().anyMatch(IndexField::isHashed);
 	}
 
-	/**
-	 * @return {@literal true} if a wildcard index field is present.
-	 * @since 3.3
-	 */
-	public boolean isWildcard() {
-		return getIndexFields().stream().anyMatch(IndexField::isWildcard);
-	}
-
 	@Override
 	public String toString() {
 
@@ -328,5 +303,4 @@ public class IndexInfo {
 		}
 		return true;
 	}
-
 }

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/index/IndexOperationsProvider.java

@@ -15,8 +15,6 @@
  */
 package org.springframework.data.mongodb.core.index;
 
-import org.springframework.lang.Nullable;
-
 /**
  * Provider interface to obtain {@link IndexOperations} by MongoDB collection name.
  *
@@ -28,22 +26,10 @@ import org.springframework.lang.Nullable;
 public interface IndexOperationsProvider {
 
 	/**
-	 * Returns the operations that can be performed on indexes.
+	 * Returns the operations that can be performed on indexes
 	 *
 	 * @param collectionName name of the MongoDB collection, must not be {@literal null}.
 	 * @return index operations on the named collection
 	 */
-	default IndexOperations indexOps(String collectionName) {
-		return indexOps(collectionName, null);
-	}
-
-	/**
-	 * Returns the operations that can be performed on indexes.
-	 *
-	 * @param collectionName name of the MongoDB collection, must not be {@literal null}.
-	 * @param type the type used for field mapping. Can be {@literal null}.
-	 * @return index operations on the named collection
-	 * @since 3.2
-	 */
-	IndexOperations indexOps(String collectionName, @Nullable Class<?> type);
+	IndexOperations indexOps(String collectionName);
 }

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/index/MongoPersistentEntityIndexResolver.java

@@ -46,9 +46,7 @@ import org.springframework.data.mongodb.core.mapping.BasicMongoPersistentEntity;
 import org.springframework.data.mongodb.core.mapping.Document;
 import org.springframework.data.mongodb.core.mapping.MongoPersistentEntity;
 import org.springframework.data.mongodb.core.mapping.MongoPersistentProperty;
-import org.springframework.data.mongodb.core.query.Collation;
 import org.springframework.data.mongodb.util.BsonUtils;
-import org.springframework.data.mongodb.util.DotPath;
 import org.springframework.data.spel.EvaluationContextProvider;
 import org.springframework.data.util.TypeInformation;
 import org.springframework.expression.EvaluationContext;
@@ -119,12 +117,9 @@ public class MongoPersistentEntityIndexResolver implements IndexResolver {
 		Assert.notNull(document, () -> String
 				.format("Entity %s is not a collection root. Make sure to annotate it with @Document!", root.getName()));
 
-		verifyWildcardIndexedProjection(root);
-
 		List<IndexDefinitionHolder> indexInformation = new ArrayList<>();
 		String collection = root.getCollection();
 		indexInformation.addAll(potentiallyCreateCompoundIndexDefinitions("", collection, root));
-		indexInformation.addAll(potentiallyCreateWildcardIndexDefinitions("", collection, root));
 		indexInformation.addAll(potentiallyCreateTextIndexDefinition(root, collection));
 
 		root.doWithProperties((PropertyHandler<MongoPersistentProperty>) property -> this
@@ -135,32 +130,13 @@ public class MongoPersistentEntityIndexResolver implements IndexResolver {
 		return indexInformation;
 	}
 
-	private void verifyWildcardIndexedProjection(MongoPersistentEntity<?> entity) {
-
-		entity.doWithAll(it -> {
-
-			if (it.isAnnotationPresent(WildcardIndexed.class)) {
-
-				WildcardIndexed indexed = it.getRequiredAnnotation(WildcardIndexed.class);
-
-				if (!ObjectUtils.isEmpty(indexed.wildcardProjection())) {
-
-					throw new MappingException(String.format(
-							"WildcardIndexed.wildcardProjection cannot be used on nested paths. Offending property: %s.%s",
-							entity.getName(), it.getName()));
-				}
-			}
-		});
-	}
-
 	private void potentiallyAddIndexForProperty(MongoPersistentEntity<?> root, MongoPersistentProperty persistentProperty,
 			List<IndexDefinitionHolder> indexes, CycleGuard guard) {
 
 		try {
 			if (persistentProperty.isEntity()) {
-				indexes.addAll(resolveIndexForEntity(mappingContext.getPersistentEntity(persistentProperty),
-						persistentProperty.isUnwrapped() ? "" : persistentProperty.getFieldName(), Path.of(persistentProperty),
-						root.getCollection(), guard));
+				indexes.addAll(resolveIndexForClass(persistentProperty.getTypeInformation().getActualType(),
+						persistentProperty.getFieldName(), Path.of(persistentProperty), root.getCollection(), guard));
 			}
 
 			List<IndexDefinitionHolder> indexDefinitions = createIndexDefinitionHolderForProperty(
@@ -184,18 +160,13 @@ public class MongoPersistentEntityIndexResolver implements IndexResolver {
 	 * @return List of {@link IndexDefinitionHolder} representing indexes for given type and its referenced property
 	 *         types. Will never be {@code null}.
 	 */
-	private List<IndexDefinitionHolder> resolveIndexForClass(TypeInformation<?> type, String dotPath, Path path,
-			String collection, CycleGuard guard) {
+	private List<IndexDefinitionHolder> resolveIndexForClass(final TypeInformation<?> type, final String dotPath,
+			final Path path, final String collection, final CycleGuard guard) {
 
-		return resolveIndexForEntity(mappingContext.getRequiredPersistentEntity(type), dotPath, path, collection, guard);
-	}
+		MongoPersistentEntity<?> entity = mappingContext.getRequiredPersistentEntity(type);
 
-	private List<IndexDefinitionHolder> resolveIndexForEntity(MongoPersistentEntity<?> entity, String dotPath, Path path,
-			String collection, CycleGuard guard) {
-
-		List<IndexDefinitionHolder> indexInformation = new ArrayList<>();
+		final List<IndexDefinitionHolder> indexInformation = new ArrayList<>();
 		indexInformation.addAll(potentiallyCreateCompoundIndexDefinitions(dotPath, collection, entity));
-		indexInformation.addAll(potentiallyCreateWildcardIndexDefinitions(dotPath, collection, entity));
 
 		entity.doWithProperties((PropertyHandler<MongoPersistentProperty>) property -> this
 				.guardAndPotentiallyAddIndexForProperty(property, dotPath, path, collection, indexInformation, guard));
@@ -208,26 +179,22 @@ public class MongoPersistentEntityIndexResolver implements IndexResolver {
 	private void guardAndPotentiallyAddIndexForProperty(MongoPersistentProperty persistentProperty, String dotPath,
 			Path path, String collection, List<IndexDefinitionHolder> indexes, CycleGuard guard) {
 
-		DotPath propertyDotPath = DotPath.from(dotPath);
-
-		if (!persistentProperty.isUnwrapped()) {
-			propertyDotPath = propertyDotPath.append(persistentProperty.getFieldName());
-		}
+		String propertyDotPath = (StringUtils.hasText(dotPath) ? dotPath + "." : "") + persistentProperty.getFieldName();
 
 		Path propertyPath = path.append(persistentProperty);
 		guard.protect(persistentProperty, propertyPath);
 
 		if (persistentProperty.isEntity()) {
 			try {
-				indexes.addAll(resolveIndexForEntity(mappingContext.getPersistentEntity(persistentProperty),
-						propertyDotPath.toString(), propertyPath, collection, guard));
+				indexes.addAll(resolveIndexForClass(persistentProperty.getTypeInformation().getActualType(), propertyDotPath,
+						propertyPath, collection, guard));
 			} catch (CyclicPropertyReferenceException e) {
 				LOGGER.info(e.getMessage());
 			}
 		}
 
-		List<IndexDefinitionHolder> indexDefinitions = createIndexDefinitionHolderForProperty(propertyDotPath.toString(),
-				collection, persistentProperty);
+		List<IndexDefinitionHolder> indexDefinitions = createIndexDefinitionHolderForProperty(propertyDotPath, collection,
+				persistentProperty);
 
 		if (!indexDefinitions.isEmpty()) {
 			indexes.addAll(indexDefinitions);
@@ -239,13 +206,6 @@ public class MongoPersistentEntityIndexResolver implements IndexResolver {
 
 		List<IndexDefinitionHolder> indices = new ArrayList<>(2);
 
-		if (persistentProperty.isUnwrapped() && (persistentProperty.isAnnotationPresent(Indexed.class)
-				|| persistentProperty.isAnnotationPresent(HashIndexed.class)
-				|| persistentProperty.isAnnotationPresent(GeoSpatialIndexed.class))) {
-			throw new InvalidDataAccessApiUsageException(
-					String.format("Index annotation not allowed on unwrapped object for path '%s'.", dotPath));
-		}
-
 		if (persistentProperty.isAnnotationPresent(Indexed.class)) {
 			indices.add(createIndexDefinition(dotPath, collection, persistentProperty));
 		} else if (persistentProperty.isAnnotationPresent(GeoSpatialIndexed.class)) {
@@ -255,11 +215,6 @@ public class MongoPersistentEntityIndexResolver implements IndexResolver {
 		if (persistentProperty.isAnnotationPresent(HashIndexed.class)) {
 			indices.add(createHashedIndexDefinition(dotPath, collection, persistentProperty));
 		}
-		if (persistentProperty.isAnnotationPresent(WildcardIndexed.class)) {
-			indices.add(createWildcardIndexDefinition(dotPath, collection,
-					persistentProperty.getRequiredAnnotation(WildcardIndexed.class),
-					mappingContext.getPersistentEntity(persistentProperty)));
-		}
 
 		return indices;
 	}
@@ -274,18 +229,6 @@ public class MongoPersistentEntityIndexResolver implements IndexResolver {
 		return createCompoundIndexDefinitions(dotPath, collection, entity);
 	}
 
-	private List<IndexDefinitionHolder> potentiallyCreateWildcardIndexDefinitions(String dotPath, String collection,
-			MongoPersistentEntity<?> entity) {
-
-		if (!entity.isAnnotationPresent(WildcardIndexed.class)) {
-			return Collections.emptyList();
-		}
-
-		return Collections.singletonList(new IndexDefinitionHolder(dotPath,
-				createWildcardIndexDefinition(dotPath, collection, entity.getRequiredAnnotation(WildcardIndexed.class), entity),
-				collection));
-	}
-
 	private Collection<? extends IndexDefinitionHolder> potentiallyCreateTextIndexDefinition(
 			MongoPersistentEntity<?> root, String collection) {
 
@@ -311,7 +254,7 @@ public class MongoPersistentEntityIndexResolver implements IndexResolver {
 		}
 
 		try {
-			appendTextIndexInformation(DotPath.empty(), Path.empty(), indexDefinitionBuilder, root,
+			appendTextIndexInformation("", Path.empty(), indexDefinitionBuilder, root,
 					new TextIndexIncludeOptions(IncludeStrategy.DEFAULT), new CycleGuard());
 		} catch (CyclicPropertyReferenceException e) {
 			LOGGER.info(e.getMessage());
@@ -332,8 +275,9 @@ public class MongoPersistentEntityIndexResolver implements IndexResolver {
 
 	}
 
-	private void appendTextIndexInformation(DotPath dotPath, Path path, TextIndexDefinitionBuilder indexDefinitionBuilder,
-			MongoPersistentEntity<?> entity, TextIndexIncludeOptions includeOptions, CycleGuard guard) {
+	private void appendTextIndexInformation(final String dotPath, final Path path,
+			final TextIndexDefinitionBuilder indexDefinitionBuilder, final MongoPersistentEntity<?> entity,
+			final TextIndexIncludeOptions includeOptions, final CycleGuard guard) {
 
 		entity.doWithProperties(new PropertyHandler<MongoPersistentProperty>() {
 
@@ -342,7 +286,7 @@ public class MongoPersistentEntityIndexResolver implements IndexResolver {
 
 				guard.protect(persistentProperty, path);
 
-				if (persistentProperty.isExplicitLanguageProperty() && dotPath.isEmpty()) {
+				if (persistentProperty.isExplicitLanguageProperty() && !StringUtils.hasText(dotPath)) {
 					indexDefinitionBuilder.withLanguageOverride(persistentProperty.getFieldName());
 				}
 
@@ -350,7 +294,8 @@ public class MongoPersistentEntityIndexResolver implements IndexResolver {
 
 				if (includeOptions.isForce() || indexed != null || persistentProperty.isEntity()) {
 
-					DotPath propertyDotPath = dotPath.append(persistentProperty.getFieldName());
+					String propertyDotPath = (StringUtils.hasText(dotPath) ? dotPath + "." : "")
+							+ persistentProperty.getFieldName();
 
 					Path propertyPath = path.append(persistentProperty);
 
@@ -363,7 +308,7 @@ public class MongoPersistentEntityIndexResolver implements IndexResolver {
 						TextIndexIncludeOptions optionsForNestedType = includeOptions;
 						if (!IncludeStrategy.FORCE.equals(includeOptions.getStrategy()) && indexed != null) {
 							optionsForNestedType = new TextIndexIncludeOptions(IncludeStrategy.FORCE,
-									new TextIndexedFieldSpec(propertyDotPath.toString(), weight));
+									new TextIndexedFieldSpec(propertyDotPath, weight));
 						}
 
 						try {
@@ -376,7 +321,7 @@ public class MongoPersistentEntityIndexResolver implements IndexResolver {
 									entity.getName()), e);
 						}
 					} else if (includeOptions.isForce() || indexed != null) {
-						indexDefinitionBuilder.onField(propertyDotPath.toString(), weight);
+						indexDefinitionBuilder.onField(propertyDotPath, weight);
 					}
 				}
 
@@ -444,32 +389,6 @@ public class MongoPersistentEntityIndexResolver implements IndexResolver {
 		return new IndexDefinitionHolder(dotPath, indexDefinition, collection);
 	}
 
-	protected IndexDefinitionHolder createWildcardIndexDefinition(String dotPath, String collection,
-			WildcardIndexed index, @Nullable MongoPersistentEntity<?> entity) {
-
-		WildcardIndex indexDefinition = new WildcardIndex(dotPath);
-
-		if (StringUtils.hasText(index.wildcardProjection()) && ObjectUtils.isEmpty(dotPath)) {
-			indexDefinition.wildcardProjection(evaluateWildcardProjection(index.wildcardProjection(), entity));
-		}
-
-		if (!index.useGeneratedName()) {
-			indexDefinition.named(pathAwareIndexName(index.name(), dotPath, entity, null));
-		}
-
-		if (StringUtils.hasText(index.partialFilter())) {
-			indexDefinition.partial(evaluatePartialFilter(index.partialFilter(), entity));
-		}
-
-		if (StringUtils.hasText(index.collation())) {
-			indexDefinition.collation(evaluateCollation(index.collation(), entity));
-		} else if (entity != null && entity.hasCollation()) {
-			indexDefinition.collation(entity.getCollation());
-		}
-
-		return new IndexDefinitionHolder(dotPath, indexDefinition, collection);
-	}
-
 	private org.bson.Document resolveCompoundIndexKeyFromStringDefinition(String dotPath, String keyDefinitionString,
 			PersistentEntity<?, ?> entity) {
 
@@ -563,7 +482,7 @@ public class MongoPersistentEntityIndexResolver implements IndexResolver {
 		return new IndexDefinitionHolder(dotPath, indexDefinition, collection);
 	}
 
-	private PartialIndexFilter evaluatePartialFilter(String filterExpression, PersistentEntity<?, ?> entity) {
+	private PartialIndexFilter evaluatePartialFilter(String filterExpression, PersistentEntity<?,?> entity) {
 
 		Object result = evaluate(filterExpression, getEvaluationContextForProperty(entity));
 
@@ -574,32 +493,6 @@ public class MongoPersistentEntityIndexResolver implements IndexResolver {
 		return PartialIndexFilter.of(BsonUtils.parse(filterExpression, null));
 	}
 
-	private org.bson.Document evaluateWildcardProjection(String projectionExpression, PersistentEntity<?, ?> entity) {
-
-		Object result = evaluate(projectionExpression, getEvaluationContextForProperty(entity));
-
-		if (result instanceof org.bson.Document) {
-			return (org.bson.Document) result;
-		}
-
-		return BsonUtils.parse(projectionExpression, null);
-	}
-
-	private Collation evaluateCollation(String collationExpression, PersistentEntity<?, ?> entity) {
-
-		Object result = evaluate(collationExpression, getEvaluationContextForProperty(entity));
-		if (result instanceof org.bson.Document) {
-			return Collation.from((org.bson.Document) result);
-		}
-		if (result instanceof Collation) {
-			return (Collation) result;
-		}
-		if (result instanceof String) {
-			return Collation.parse(result.toString());
-		}
-		throw new IllegalStateException("Cannot parse collation " + result);
-
-	}
 
 	/**
 	 * Creates {@link HashedIndex} wrapped in {@link IndexDefinitionHolder} out of {@link HashIndexed} for a given
@@ -740,7 +633,7 @@ public class MongoPersistentEntityIndexResolver implements IndexResolver {
 
 		MongoPersistentProperty property = association.getInverse();
 
-		DotPath propertyDotPath = DotPath.from(path).append(property.getFieldName());
+		String propertyDotPath = (StringUtils.hasText(path) ? path + "." : "") + property.getFieldName();
 
 		if (property.isAnnotationPresent(GeoSpatialIndexed.class) || property.isAnnotationPresent(TextIndexed.class)) {
 			throw new MappingException(
@@ -748,8 +641,8 @@ public class MongoPersistentEntityIndexResolver implements IndexResolver {
 							propertyDotPath));
 		}
 
-		List<IndexDefinitionHolder> indexDefinitions = createIndexDefinitionHolderForProperty(propertyDotPath.toString(),
-				collection, property);
+		List<IndexDefinitionHolder> indexDefinitions = createIndexDefinitionHolderForProperty(propertyDotPath, collection,
+				property);
 
 		if (!indexDefinitions.isEmpty()) {
 			indexes.addAll(indexDefinitions);
@@ -1089,11 +982,6 @@ public class MongoPersistentEntityIndexResolver implements IndexResolver {
 		public org.bson.Document getIndexOptions() {
 			return indexDefinition.getIndexOptions();
 		}
-
-		@Override
-		public String toString() {
-			return "IndexDefinitionHolder{" + "indexKeys=" + getIndexKeys() + '}';
-		}
 	}
 
 	/**

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/index/WildcardIndex.java

@@ -1,198 +0,0 @@
-/*
- * Copyright 2021 the original author or authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      https://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.springframework.data.mongodb.core.index;
-
-import java.time.Duration;
-import java.util.LinkedHashMap;
-import java.util.Map;
-import java.util.concurrent.TimeUnit;
-
-import org.bson.Document;
-import org.springframework.lang.Nullable;
-import org.springframework.util.CollectionUtils;
-import org.springframework.util.StringUtils;
-
-/**
- * {@link WildcardIndex} is a specific {@link Index} that can be used to include all fields into an index based on the
- * {@code $**" : 1} pattern on a root object (the one typically carrying the
- * {@link org.springframework.data.mongodb.core.mapping.Document} annotation). On those it is possible to use
- * {@link #wildcardProjectionInclude(String...)} and {@link #wildcardProjectionExclude(String...)} to define specific
- * paths for in-/exclusion.
- * <p />
- * It can also be used to define an index on a specific field path and its subfields, e.g.
- * {@code "path.to.field.$**" : 1}. <br />
- * Note that {@literal wildcardProjections} are not allowed in this case.
- * <p />
- * <strong>LIMITATIONS</strong><br />
- * <ul>
- * <li>{@link #unique() Unique} and {@link #expire(long) ttl} options are not supported.</li>
- * <li>Keys used for sharding must not be included</li>
- * <li>Cannot be used to generate any type of geo index.</li>
- * </ul>
- *
- * @author Christoph Strobl
- * @see <a href= "https://docs.mongodb.com/manual/core/index-wildcard/">MongoDB Reference Documentation: Wildcard
- *      Indexes/</a>
- * @since 3.3
- */
-public class WildcardIndex extends Index {
-
-	private @Nullable String fieldName;
-	private final Map<String, Object> wildcardProjection = new LinkedHashMap<>();
-
-	/**
-	 * Create a new instance of {@link WildcardIndex} using {@code $**}.
-	 */
-	public WildcardIndex() {}
-
-	/**
-	 * Create a new instance of {@link WildcardIndex} for the given {@literal path}. If no {@literal path} is provided the
-	 * index will be considered a root one using {@code $**}. <br />
-	 * <strong>NOTE</strong> {@link #wildcardProjectionInclude(String...)}, {@link #wildcardProjectionExclude(String...)}
-	 * can only be used for top level index definitions having an {@literal empty} or {@literal null} path.
-	 *
-	 * @param path can be {@literal null}. If {@literal null} all fields will be indexed.
-	 */
-	public WildcardIndex(@Nullable String path) {
-		this.fieldName = path;
-	}
-
-	/**
-	 * Include the {@code _id} field in {@literal wildcardProjection}.
-	 *
-	 * @return this.
-	 */
-	public WildcardIndex includeId() {
-
-		wildcardProjection.put("_id", 1);
-		return this;
-	}
-
-	/**
-	 * Set the index name to use.
-	 *
-	 * @param name
-	 * @return this.
-	 */
-	@Override
-	public WildcardIndex named(String name) {
-
-		super.named(name);
-		return this;
-	}
-
-	/**
-	 * Unique option is not supported.
-	 *
-	 * @throws UnsupportedOperationException not supported for wildcard indexes.
-	 */
-	@Override
-	public Index unique() {
-		throw new UnsupportedOperationException("Wildcard Index does not support 'unique'.");
-	}
-
-	/**
-	 * ttl option is not supported.
-	 *
-	 * @throws UnsupportedOperationException not supported for wildcard indexes.
-	 */
-	@Override
-	public Index expire(long seconds) {
-		throw new UnsupportedOperationException("Wildcard Index does not support 'ttl'.");
-	}
-
-	/**
-	 * ttl option is not supported.
-	 *
-	 * @throws UnsupportedOperationException not supported for wildcard indexes.
-	 */
-	@Override
-	public Index expire(long value, TimeUnit timeUnit) {
-		throw new UnsupportedOperationException("Wildcard Index does not support 'ttl'.");
-	}
-
-	/**
-	 * ttl option is not supported.
-	 *
-	 * @throws UnsupportedOperationException not supported for wildcard indexes.
-	 */
-	@Override
-	public Index expire(Duration duration) {
-		throw new UnsupportedOperationException("Wildcard Index does not support 'ttl'.");
-	}
-
-	/**
-	 * Add fields to be included from indexing via {@code wildcardProjection}. <br />
-	 * This option is only allowed on {@link WildcardIndex#WildcardIndex() top level} wildcard indexes.
-	 *
-	 * @param paths must not be {@literal null}.
-	 * @return this.
-	 */
-	public WildcardIndex wildcardProjectionInclude(String... paths) {
-
-		for (String path : paths) {
-			wildcardProjection.put(path, 1);
-		}
-		return this;
-	}
-
-	/**
-	 * Add fields to be excluded from indexing via {@code wildcardProjection}. <br />
-	 * This option is only allowed on {@link WildcardIndex#WildcardIndex() top level} wildcard indexes.
-	 *
-	 * @param paths must not be {@literal null}.
-	 * @return this.
-	 */
-	public WildcardIndex wildcardProjectionExclude(String... paths) {
-
-		for (String path : paths) {
-			wildcardProjection.put(path, 0);
-		}
-		return this;
-	}
-
-	/**
-	 * Set the fields to be in-/excluded from indexing via {@code wildcardProjection}. <br />
-	 * This option is only allowed on {@link WildcardIndex#WildcardIndex() top level} wildcard indexes.
-	 *
-	 * @param includeExclude must not be {@literal null}.
-	 * @return this.
-	 */
-	public WildcardIndex wildcardProjection(Map<String, Object> includeExclude) {
-
-		wildcardProjection.putAll(includeExclude);
-		return this;
-	}
-
-	private String getTargetFieldName() {
-		return StringUtils.hasText(fieldName) ? (fieldName + ".$**") : "$**";
-	}
-
-	@Override
-	public Document getIndexKeys() {
-		return new Document(getTargetFieldName(), 1);
-	}
-
-	@Override
-	public Document getIndexOptions() {
-
-		Document options = new Document(super.getIndexOptions());
-		if (!CollectionUtils.isEmpty(wildcardProjection)) {
-			options.put("wildcardProjection", new Document(wildcardProjection));
-		}
-		return options;
-	}
-}

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/index/WildcardIndexed.java

@@ -1,130 +0,0 @@
-/*
- * Copyright 2021 the original author or authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      https://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.springframework.data.mongodb.core.index;
-
-import java.lang.annotation.Documented;
-import java.lang.annotation.ElementType;
-import java.lang.annotation.Retention;
-import java.lang.annotation.RetentionPolicy;
-import java.lang.annotation.Target;
-
-/**
- * Annotation for an entity or property that should be used as key for a
- * <a href="https://docs.mongodb.com/manual/core/index-wildcard/">Wildcard Index</a>. <br />
- * If placed on a {@link ElementType#TYPE type} that is a root level domain entity (one having an
- * {@link org.springframework.data.mongodb.core.mapping.Document} annotation) will advise the index creator to create a
- * wildcard index for it.
- *
- * <pre class="code">
- *
- * &#64;Document
- * &#64;WildcardIndexed
- * public class Product {
- *     ...
- * }
- *
- * db.product.createIndex({ "$**" : 1 } , {})
- * </pre>
- *
- * {@literal wildcardProjection} can be used to specify keys to in-/exclude in the index.
- *
- * <pre class="code">
- *
- * &#64;Document
- * &#64;WildcardIndexed(wildcardProjection = "{ 'userMetadata.age' : 0 }")
- * public class User {
- *     private &#64;Id String id;
- *     private UserMetadata userMetadata;
- * }
- *
- *
- * db.user.createIndex(
- *   { "$**" : 1 },
- *   { "wildcardProjection" :
- *     { "userMetadata.age" : 0 }
- *   }
- * )
- * </pre>
- *
- * Wildcard indexes can also be expressed by adding the annotation directly to the field. Please note that
- * {@literal wildcardProjection} is not allowed on nested paths.
- *
- * <pre class="code">
- * &#64;Document
- * public class User {
- *
- *     private &#64;Id String id;
- *
- *     &#64;WildcardIndexed
- *     private UserMetadata userMetadata;
- * }
- *
- *
- * db.user.createIndex({ "userMetadata.$**" : 1 }, {})
- * </pre>
- *
- * @author Christoph Strobl
- * @since 3.3
- */
-@Documented
-@Target({ ElementType.TYPE, ElementType.FIELD })
-@Retention(RetentionPolicy.RUNTIME)
-public @interface WildcardIndexed {
-
-	/**
-	 * Index name either as plain value or as {@link org.springframework.expression.spel.standard.SpelExpression template
-	 * expression}. <br />
-	 * <br />
-	 * The name will only be applied as is when defined on root level. For usage on nested or embedded structures the
-	 * provided name will be prefixed with the path leading to the entity.
-	 *
-	 * @return empty by default.
-	 */
-	String name() default "";
-
-	/**
-	 * If set to {@literal true} then MongoDB will ignore the given index name and instead generate a new name. Defaults
-	 * to {@literal false}.
-	 *
-	 * @return {@literal false} by default.
-	 */
-	boolean useGeneratedName() default false;
-
-	/**
-	 * Only index the documents in a collection that meet a specified {@link IndexFilter filter expression}. <br />
-	 *
-	 * @return empty by default.
-	 * @see <a href=
-	 *      "https://docs.mongodb.com/manual/core/index-partial/">https://docs.mongodb.com/manual/core/index-partial/</a>
-	 */
-	String partialFilter() default "";
-
-	/**
-	 * Explicitly specify sub fields to be in-/excluded as a {@link org.bson.Document#parse(String) prasable} String.
-	 * <br />
-	 * <strong>NOTE: </strong>Can only be applied on root level documents.
-	 *
-	 * @return empty by default.
-	 */
-	String wildcardProjection() default "";
-
-	/**
-	 * Defines the collation to apply.
-	 *
-	 * @return an empty {@link String} by default.
-	 */
-	String collation() default "";
-}

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/mapping/BasicMongoPersistentEntity.java

@@ -164,8 +164,7 @@ public class BasicMongoPersistentEntity<T> extends BasicPersistentEntity<T, Mong
 	@Override
 	public org.springframework.data.mongodb.core.query.Collation getCollation() {
 
-		Object collationValue = collationExpression != null
-				? collationExpression.getValue(getEvaluationContext(null), String.class)
+		Object collationValue = collationExpression != null ? collationExpression.getValue(getEvaluationContext(null), String.class)
 				: this.collation;
 
 		if (collationValue == null) {

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/mapping/BasicMongoPersistentProperty.java

@@ -41,14 +41,13 @@ import org.springframework.util.StringUtils;
  * @author Thomas Darimont
  * @author Christoph Strobl
  * @author Mark Paluch
- * @author Divya Srivastava
  */
 public class BasicMongoPersistentProperty extends AnnotationBasedPersistentProperty<MongoPersistentProperty>
 		implements MongoPersistentProperty {
 
 	private static final Logger LOG = LoggerFactory.getLogger(BasicMongoPersistentProperty.class);
 
-	public static final String ID_FIELD_NAME = "_id";
+	private static final String ID_FIELD_NAME = "_id";
 	private static final String LANGUAGE_FIELD_NAME = "language";
 	private static final Set<Class<?>> SUPPORTED_ID_TYPES = new HashSet<Class<?>>();
 	private static final Set<String> SUPPORTED_ID_PROPERTY_NAMES = new HashSet<String>();
@@ -215,19 +214,6 @@ public class BasicMongoPersistentProperty extends AnnotationBasedPersistentPrope
 		return annotation != null ? annotation.order() : Integer.MAX_VALUE;
 	}
 
-	/*
-	 * (non-Javadoc)
-	 * @see org.springframework.data.mongodb.core.mapping.MongoPersistentProperty#skipNullValues()
-	 */
-	@Override
-	public boolean writeNullValues() {
-
-		org.springframework.data.mongodb.core.mapping.Field annotation = findAnnotation(
-				org.springframework.data.mongodb.core.mapping.Field.class);
-
-		return annotation != null && annotation.write() == Field.Write.ALWAYS;
-	}
-
 	/*
 	 * (non-Javadoc)
 	 * @see org.springframework.data.mapping.model.AbstractPersistentProperty#createAssociation()
@@ -245,15 +231,6 @@ public class BasicMongoPersistentProperty extends AnnotationBasedPersistentPrope
 		return isAnnotationPresent(DBRef.class);
 	}
 
-	/*
-	 * (non-Javadoc)
-	 * @see org.springframework.data.mongodb.core.mapping.MongoPersistentProperty#isDocumentReference()
-	 */
-	@Override
-	public boolean isDocumentReference() {
-		return isAnnotationPresent(DocumentReference.class);
-	}
-
 	/*
 	 * (non-Javadoc)
 	 * @see org.springframework.data.mongodb.core.mapping.MongoPersistentProperty#getDBRef()
@@ -263,16 +240,6 @@ public class BasicMongoPersistentProperty extends AnnotationBasedPersistentPrope
 		return findAnnotation(DBRef.class);
 	}
 
-	/*
-	 * (non-Javadoc)
-	 * @see org.springframework.data.mongodb.core.mapping.MongoPersistentProperty#getDocumentReference()
-	 */
-	@Nullable
-	@Override
-	public DocumentReference getDocumentReference() {
-		return findAnnotation(DocumentReference.class);
-	}
-
 	/*
 	 * (non-Javadoc)
 	 * @see org.springframework.data.mongodb.core.mapping.MongoPersistentProperty#isLanguageProperty()
@@ -299,5 +266,4 @@ public class BasicMongoPersistentProperty extends AnnotationBasedPersistentPrope
 	public boolean isTextScoreProperty() {
 		return isAnnotationPresent(TextScore.class);
 	}
-
 }

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/mapping/CachingMongoPersistentProperty.java

@@ -33,7 +33,6 @@ public class CachingMongoPersistentProperty extends BasicMongoPersistentProperty
 	private boolean dbRefResolved;
 	private @Nullable DBRef dbref;
 	private @Nullable String fieldName;
-	private @Nullable Boolean writeNullValues;
 	private @Nullable Class<?> fieldType;
 	private @Nullable Boolean usePropertyAccess;
 	private @Nullable Boolean isTransient;
@@ -91,20 +90,6 @@ public class CachingMongoPersistentProperty extends BasicMongoPersistentProperty
 		return this.fieldName;
 	}
 
-	/*
-	 * (non-Javadoc)
-	 * @see org.springframework.data.mongodb.core.mapping.BasicMongoPersistentProperty#skipNullValues()
-	 */
-	@Override
-	public boolean writeNullValues() {
-
-		if (this.writeNullValues == null) {
-			this.writeNullValues = super.writeNullValues();
-		}
-
-		return this.writeNullValues;
-	}
-
 	/*
 	 * (non-Javadoc)
 	 * @see org.springframework.data.mongodb.core.mapping.BasicMongoPersistentProperty#getFieldType()

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/mapping/Document.java

@@ -41,7 +41,7 @@ public @interface Document {
 	 * The collection the document representing the entity is supposed to be stored in. If not configured, a default
 	 * collection name will be derived from the type's name. The attribute supports SpEL expressions to dynamically
 	 * calculate the collection to based on a per operation basis.
-	 * 
+	 *
 	 * @return the name of the collection to be used.
 	 */
 	@AliasFor("collection")
@@ -51,7 +51,7 @@ public @interface Document {
 	 * The collection the document representing the entity is supposed to be stored in. If not configured, a default
 	 * collection name will be derived from the type's name. The attribute supports SpEL expressions to dynamically
 	 * calculate the collection to based on a per operation basis.
-	 * 
+	 *
 	 * @return the name of the collection to be used.
 	 */
 	@AliasFor("value")

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/mapping/DocumentPointer.java

@@ -1,35 +0,0 @@
-/*
- * Copyright 2021 the original author or authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      https://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.springframework.data.mongodb.core.mapping;
-
-/**
- * A custom pointer to a linked document to be used along with {@link DocumentReference} for storing the linkage value.
- *
- * @author Christoph Strobl
- * @since 3.3
- */
-@FunctionalInterface
-public interface DocumentPointer<T> {
-
-	/**
-	 * The actual pointer value. This can be any simple type, like a {@link String} or {@link org.bson.types.ObjectId} or
-	 * a {@link org.bson.Document} holding more information like the target collection, multiple fields forming the key,
-	 * etc.
-	 *
-	 * @return the value stored in MongoDB and used for constructing the {@link DocumentReference#lookup() lookup query}.
-	 */
-	T getPointer();
-}

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/mapping/DocumentReference.java

@@ -1,132 +0,0 @@
-/*
- * Copyright 2021 the original author or authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      https://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.springframework.data.mongodb.core.mapping;
-
-import java.lang.annotation.Documented;
-import java.lang.annotation.ElementType;
-import java.lang.annotation.Retention;
-import java.lang.annotation.RetentionPolicy;
-import java.lang.annotation.Target;
-
-import org.springframework.data.annotation.Reference;
-import org.springframework.data.mongodb.MongoDatabaseFactory;
-
-/**
- * A {@link DocumentReference} allows referencing entities in MongoDB using a flexible schema. While the goal is the
- * same as when using {@link DBRef}, the store representation is different. The reference can be anything, a single
- * value, an entire {@link org.bson.Document}, basically everything that can be stored in MongoDB. By default, the
- * mapping layer will use the referenced entities {@literal id} value for storage and retrieval.
- *
- * <pre class="code">
- * public class Account {
- *   private String id;
- *   private Float total;
- * }
- *
- * public class Person {
- *   private String id;
- *   &#64;DocumentReference
- *   private List&lt;Account&gt; accounts;
- * }
- *
- * Account account = ...
- *
- * mongoTemplate.insert(account);
- *
- * template.update(Person.class)
- *   .matching(where("id").is(...))
- *   .apply(new Update().push("accounts").value(account))
- *   .first();
- * </pre>
- *
- * {@link #lookup()} allows defining a query filter that is independent from the {@literal _id} field and in combination
- * with {@link org.springframework.data.convert.WritingConverter writing converters} offers a flexible way of defining
- * references between entities.
- *
- * <pre class="code">
- * public class Book {
- * 	private ObjectId id;
- * 	private String title;
- *
- * 	&#64;Field("publisher_ac") &#64;DocumentReference(lookup = "{ 'acronym' : ?#{#target} }") private Publisher publisher;
- * }
- *
- * public class Publisher {
- *
- * 	private ObjectId id;
- * 	private String acronym;
- * 	private String name;
- *
- * 	&#64;DocumentReference(lazy = true) private List&lt;Book&gt; books;
- * }
- *
- * &#64;WritingConverter
- * public class PublisherReferenceConverter implements Converter&lt;Publisher, DocumentPointer&lt;String&gt;&gt; {
- *
- * 	public DocumentPointer&lt;String&gt; convert(Publisher source) {
- * 		return () -> source.getAcronym();
- * 	}
- * }
- * </pre>
- *
- * @author Christoph Strobl
- * @since 3.3
- * @see <a href="https://docs.mongodb.com/manual/reference/database-references/#std-label-document-references">MongoDB
- *      Reference Documentation</a>
- */
-@Documented
-@Retention(RetentionPolicy.RUNTIME)
-@Target({ ElementType.FIELD })
-@Reference
-public @interface DocumentReference {
-
-	/**
-	 * The database the referenced entity resides in. Uses the default database provided by
-	 * {@link org.springframework.data.mongodb.MongoDatabaseFactory} if empty.
-	 *
-	 * @see MongoDatabaseFactory#getMongoDatabase()
-	 * @see MongoDatabaseFactory#getMongoDatabase(String)
-	 */
-	String db() default "";
-
-	/**
-	 * The collection the referenced entity resides in. Defaults to the collection of the referenced entity type.
-	 *
-	 * @see MongoPersistentEntity#getCollection()
-	 */
-	String collection() default "";
-
-	/**
-	 * The single document lookup query. In case of an {@link java.util.Collection} or {@link java.util.Map} property the
-	 * individual lookups are combined via an {@code $or} operator. {@code target} points to the source value (or
-	 * document) stored at the reference property. Properties of {@code target} can be used to define the reference query.
-	 *
-	 * @return an {@literal _id} based lookup.
-	 */
-	String lookup() default "{ '_id' : ?#{#target} }";
-
-	/**
-	 * A specific sort.
-	 */
-	String sort() default "";
-
-	/**
-	 * Controls whether the referenced entity should be loaded lazily. This defaults to {@literal false}.
-	 *
-	 * @return {@literal false} by default.
-	 */
-	boolean lazy() default false;
-}

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/mapping/Field.java

@@ -28,7 +28,6 @@ import org.springframework.core.annotation.AliasFor;
  *
  * @author Oliver Gierke
  * @author Christoph Strobl
- * @author Divya Srivastava
  */
 @Documented
 @Retention(RetentionPolicy.RUNTIME)
@@ -66,34 +65,4 @@ public @interface Field {
 	 * @since 2.2
 	 */
 	FieldType targetType() default FieldType.IMPLICIT;
-
-	/**
-	 * Write rules when to include a property value upon conversion. If set to {@link Write#NON_NULL} (default)
-	 * {@literal null} values are not written to the target {@code Document}. Setting the value to {@link Write#ALWAYS}
-	 * explicitly adds an entry for the given field holding {@literal null} as a value {@code 'fieldName' : null }.
-	 * <p />
-	 * <strong>NOTE</strong>Setting the value to {@link Write#ALWAYS} may lead to increased document size.
-	 *
-	 * @return {@link Write#NON_NULL} by default.
-	 * @since 3.3
-	 */
-	Write write() default Write.NON_NULL;
-
-	/**
-	 * Enumeration of write strategies to define when a property is included for write conversion.
-	 *
-	 * @since 3.3
-	 */
-	enum Write {
-
-		/**
-		 * Value that indicates that property is to be always included, independent of value of the property.
-		 */
-		ALWAYS,
-
-		/**
-		 * Value that indicates that only properties with non-{@literal null} values are to be included.
-		 */
-		NON_NULL
-	}
 }

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/mapping/MongoMappingContext.java

@@ -26,7 +26,6 @@ import org.springframework.data.mapping.model.FieldNamingStrategy;
 import org.springframework.data.mapping.model.Property;
 import org.springframework.data.mapping.model.PropertyNameFieldNamingStrategy;
 import org.springframework.data.mapping.model.SimpleTypeHolder;
-import org.springframework.data.util.NullableWrapperConverters;
 import org.springframework.data.util.TypeInformation;
 import org.springframework.lang.Nullable;
 
@@ -36,9 +35,8 @@ import org.springframework.lang.Nullable;
  *
  * @author Jon Brisbin
  * @author Oliver Gierke
- * @author Christoph Strobl
  */
-public class MongoMappingContext extends AbstractMappingContext<MongoPersistentEntity<?>, MongoPersistentProperty>
+public class MongoMappingContext extends AbstractMappingContext<BasicMongoPersistentEntity<?>, MongoPersistentProperty>
 		implements ApplicationContextAware {
 
 	private static final FieldNamingStrategy DEFAULT_NAMING_STRATEGY = PropertyNameFieldNamingStrategy.INSTANCE;
@@ -70,11 +68,6 @@ public class MongoMappingContext extends AbstractMappingContext<MongoPersistentE
 	 */
 	@Override
 	protected boolean shouldCreatePersistentEntityFor(TypeInformation<?> type) {
-
-		if (NullableWrapperConverters.supports(type.getType())) {
-			return false;
-		}
-
 		return !MongoSimpleTypes.HOLDER.isSimpleType(type.getType()) && !AbstractMap.class.isAssignableFrom(type.getType());
 	}
 
@@ -83,7 +76,7 @@ public class MongoMappingContext extends AbstractMappingContext<MongoPersistentE
 	 * @see org.springframework.data.mapping.AbstractMappingContext#createPersistentProperty(java.lang.reflect.Field, java.beans.PropertyDescriptor, org.springframework.data.mapping.MutablePersistentEntity, org.springframework.data.mapping.SimpleTypeHolder)
 	 */
 	@Override
-	public MongoPersistentProperty createPersistentProperty(Property property, MongoPersistentEntity<?> owner,
+	public MongoPersistentProperty createPersistentProperty(Property property, BasicMongoPersistentEntity<?> owner,
 			SimpleTypeHolder simpleTypeHolder) {
 		return new CachingMongoPersistentProperty(property, owner, simpleTypeHolder, fieldNamingStrategy);
 	}
@@ -94,7 +87,7 @@ public class MongoMappingContext extends AbstractMappingContext<MongoPersistentE
 	 */
 	@Override
 	protected <T> BasicMongoPersistentEntity<T> createPersistentEntity(TypeInformation<T> typeInformation) {
-		return new BasicMongoPersistentEntity<>(typeInformation);
+		return new BasicMongoPersistentEntity<T>(typeInformation);
 	}
 
 	/*
@@ -103,6 +96,7 @@ public class MongoMappingContext extends AbstractMappingContext<MongoPersistentE
 	 */
 	@Override
 	public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
+
 		super.setApplicationContext(applicationContext);
 	}
 
@@ -132,17 +126,4 @@ public class MongoMappingContext extends AbstractMappingContext<MongoPersistentE
 	public void setAutoIndexCreation(boolean autoCreateIndexes) {
 		this.autoIndexCreation = autoCreateIndexes;
 	}
-
-	@Nullable
-	@Override
-	public MongoPersistentEntity<?> getPersistentEntity(MongoPersistentProperty persistentProperty) {
-
-		MongoPersistentEntity<?> entity = super.getPersistentEntity(persistentProperty);
-
-		if (entity == null || !persistentProperty.isUnwrapped()) {
-			return entity;
-		}
-
-		return new UnwrappedMongoPersistentEntity<>(entity, new UnwrapEntityContext(persistentProperty));
-	}
 }

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/mapping/MongoPersistentEntity.java

@@ -16,7 +16,6 @@
 package org.springframework.data.mongodb.core.mapping;
 
 import org.springframework.data.mapping.PersistentEntity;
-import org.springframework.data.mapping.model.MutablePersistentEntity;
 import org.springframework.lang.Nullable;
 
 /**
@@ -25,7 +24,7 @@ import org.springframework.lang.Nullable;
  * @author Oliver Gierke
  * @author Christoph Strobl
  */
-public interface MongoPersistentEntity<T> extends MutablePersistentEntity<T, MongoPersistentProperty> {
+public interface MongoPersistentEntity<T> extends PersistentEntity<T, MongoPersistentProperty> {
 
 	/**
 	 * Returns the collection the entity shall be persisted to.
@@ -94,12 +93,4 @@ public interface MongoPersistentEntity<T> extends MutablePersistentEntity<T, Mon
 		return getShardKey().isSharded();
 	}
 
-	/**
-	 * @return {@literal true} if the entity should be unwrapped.
-	 * @since 3.2
-	 */
-	default boolean isUnwrapped() {
-		return false;
-	}
-
 }

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/mapping/MongoPersistentProperty.java

@@ -28,7 +28,6 @@ import org.springframework.lang.Nullable;
  * @author Patryk Wasik
  * @author Thomas Darimont
  * @author Christoph Strobl
- * @author Divya Srivastava
  */
 public interface MongoPersistentProperty extends PersistentProperty<MongoPersistentProperty> {
 
@@ -55,15 +54,6 @@ public interface MongoPersistentProperty extends PersistentProperty<MongoPersist
 	 */
 	int getFieldOrder();
 
-	/**
-	 * Returns whether the property should be written to the database if its value is {@literal null}.
-	 *
-	 * @return
-	 * @since 3.3
-	 * @see Field.Write
-	 */
-	boolean writeNullValues();
-
 	/**
 	 * Returns whether the property is a {@link com.mongodb.DBRef}. If this returns {@literal true} you can expect
 	 * {@link #getDBRef()} to return an non-{@literal null} value.
@@ -72,15 +62,6 @@ public interface MongoPersistentProperty extends PersistentProperty<MongoPersist
 	 */
 	boolean isDbReference();
 
-	/**
-	 * Returns whether the property is a {@link DocumentReference}. If this returns {@literal true} you can expect
-	 * {@link #getDocumentReference()} to return an non-{@literal null} value.
-	 *
-	 * @return
-	 * @since 3.3
-	 */
-	boolean isDocumentReference();
-
 	/**
 	 * Returns whether the property is explicitly marked as an identifier property of the owning {@link PersistentEntity}.
 	 * A property is an explicit id property if it is annotated with @see {@link Id}.
@@ -124,16 +105,6 @@ public interface MongoPersistentProperty extends PersistentProperty<MongoPersist
 	@Nullable
 	DBRef getDBRef();
 
-	/**
-	 * Returns the {@link DocumentReference} if the property is a reference.
-	 *
-	 * @see #isDocumentReference()
-	 * @return {@literal null} if not present.
-	 * @since 3.3
-	 */
-	@Nullable
-	DocumentReference getDocumentReference();
-
 	/**
 	 * Returns whether property access shall be used for reading the property value. This means it will use the getter
 	 * instead of field access.
@@ -152,14 +123,6 @@ public interface MongoPersistentProperty extends PersistentProperty<MongoPersist
 		return field != null ? !FieldType.IMPLICIT.equals(field.targetType()) : false;
 	}
 
-	/**
-	 * @return {@literal true} if the property should be unwrapped.
-	 * @since 3.2
-	 */
-	default boolean isUnwrapped() {
-		return isEntity() && isAnnotationPresent(Unwrapped.class);
-	}
-
 	/**
 	 * Simple {@link Converter} implementation to transform a {@link MongoPersistentProperty} into its field name.
 	 *
@@ -174,10 +137,7 @@ public interface MongoPersistentProperty extends PersistentProperty<MongoPersist
 		 * @see org.springframework.core.convert.converter.Converter#convert(java.lang.Object)
 		 */
 		public String convert(MongoPersistentProperty source) {
-			if (!source.isUnwrapped()) {
-				return source.getFieldName();
-			}
-			return "";
+			return source.getFieldName();
 		}
 	}
 }

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/mapping/TimeSeries.java

@@ -1,87 +0,0 @@
-/*
- * Copyright 2021 the original author or authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      https://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.springframework.data.mongodb.core.mapping;
-
-import java.lang.annotation.ElementType;
-import java.lang.annotation.Inherited;
-import java.lang.annotation.Retention;
-import java.lang.annotation.RetentionPolicy;
-import java.lang.annotation.Target;
-
-import org.springframework.core.annotation.AliasFor;
-import org.springframework.data.mongodb.core.timeseries.Granularity;
-
-/**
- * Identifies a domain object to be persisted to a MongoDB Time Series collection.
- *
- * @author Christoph Strobl
- * @since 3.3
- * @see <a href=
- *      "https://docs.mongodb.com/manual/core/timeseries-collections">https://docs.mongodb.com/manual/core/timeseries-collections</a>
- */
-@Inherited
-@Retention(RetentionPolicy.RUNTIME)
-@Target({ ElementType.TYPE })
-@Document
-public @interface TimeSeries {
-
-	/**
-	 * The collection the document representing the entity is supposed to be stored in. If not configured, a default
-	 * collection name will be derived from the type's name. The attribute supports SpEL expressions to dynamically
-	 * calculate the collection based on a per operation basis.
-	 *
-	 * @return the name of the collection to be used.
-	 * @see Document#collection()
-	 */
-	@AliasFor(annotation = Document.class, attribute = "collection")
-	String collection() default "";
-
-	/**
-	 * Name of the property which contains the date in each time series document. <br />
-	 * Translation of property names to {@link Field#name() annotated fieldnames} will be considered during the mapping
-	 * process.
-	 *
-	 * @return never {@literal null}.
-	 */
-	String timeField();
-
-	/**
-	 * The name of the field which contains metadata in each time series document. Should not be the {@literal id} nor
-	 * {@link #timeField()} nor point to an {@literal array} or {@link java.util.Collection}. <br />
-	 * Translation of property names to {@link Field#name() annotated fieldnames} will be considered during the mapping
-	 * process.
-	 *
-	 * @return empty {@link String} by default.
-	 */
-	String metaField() default "";
-
-	/**
-	 * Select the {@link Granularity granularity} parameter to define how data in the time series collection is organized.
-	 *
-	 * @return {@link Granularity#DEFAULT server default} by default.
-	 */
-	Granularity granularity() default Granularity.DEFAULT;
-
-	/**
-	 * Defines the collation to apply when executing a query or creating indexes.
-	 *
-	 * @return an empty {@link String} by default.
-	 * @see Document#collation()
-	 */
-	@AliasFor(annotation = Document.class, attribute = "collation")
-	String collation() default "";
-
-}

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/mapping/UnwrapEntityContext.java

@@ -1,64 +0,0 @@
-/*
- * Copyright 2021 the original author or authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      https://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.springframework.data.mongodb.core.mapping;
-
-import org.springframework.util.ObjectUtils;
-
-/**
- * @author Christoph Strobl
- * @author Rogério Meneguelli Gatto
- * @since 3.2
- */
-class UnwrapEntityContext {
-
-	private final MongoPersistentProperty property;
-
-	public UnwrapEntityContext(MongoPersistentProperty property) {
-		this.property = property;
-	}
-
-	public MongoPersistentProperty getProperty() {
-		return property;
-	}
-
-	/*
-	 * (non-Javadoc)
-	 * @see java.lang.Object#equals(java.lang.Object)
-	 */
-	@Override
-	public boolean equals(Object obj) {
-
-		if (this == obj) {
-			return true;
-		}
-
-		if (obj == null || getClass() != obj.getClass()) {
-			return false;
-		}
-
-		UnwrapEntityContext that = (UnwrapEntityContext) obj;
-		return ObjectUtils.nullSafeEquals(property, that.property);
-	}
-
-	/*
-	 * (non-Javadoc)
-	 * @see java.lang.Object#hashCode()
-	 */
-	@Override
-	public int hashCode() {
-		return ObjectUtils.nullSafeHashCode(property);
-	}
-}

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/mapping/Unwrapped.java

@@ -1,136 +0,0 @@
-/*
- * Copyright 2021 the original author or authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      https://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.springframework.data.mongodb.core.mapping;
-
-import java.lang.annotation.Documented;
-import java.lang.annotation.ElementType;
-import java.lang.annotation.Retention;
-import java.lang.annotation.RetentionPolicy;
-import java.lang.annotation.Target;
-
-import javax.annotation.meta.When;
-
-import org.springframework.core.annotation.AliasFor;
-
-/**
- * The annotation to configure a value object as flattened out in the target document.
- * <p />
- * Depending on the {@link OnEmpty value} of {@link #onEmpty()} the property is set to {@literal null} or an empty
- * instance in the case all unwrapped values are {@literal null} when reading from the result set.
- *
- * @author Christoph Strobl
- * @since 3.2
- */
-@Documented
-@Retention(value = RetentionPolicy.RUNTIME)
-@Target(value = { ElementType.ANNOTATION_TYPE, ElementType.FIELD, ElementType.METHOD })
-public @interface Unwrapped {
-
-	/**
-	 * Set the load strategy for the unwrapped object if all contained fields yield {@literal null} values.
-	 * <p />
-	 * {@link Nullable @Unwrapped.Nullable} and {@link Empty @Unwrapped.Empty} offer shortcuts for this.
-	 *
-	 * @return never {@link} null.
-	 */
-	OnEmpty onEmpty();
-
-	/**
-	 * @return prefix for columns in the unwrapped value object. An empty {@link String} by default.
-	 */
-	String prefix() default "";
-
-	/**
-	 * Load strategy to be used {@link Unwrapped#onEmpty()}.
-	 *
-	 * @author Christoph Strobl
-	 */
-	enum OnEmpty {
-		USE_NULL, USE_EMPTY
-	}
-
-	/**
-	 * Shortcut for a nullable unwrapped property.
-	 *
-	 * <pre class="code">
-	 * &#64;Unwrapped.Nullable private Address address;
-	 * </pre>
-	 *
-	 * as alternative to the more verbose
-	 *
-	 * <pre class="code">
-	 * &#64;Unwrapped(onEmpty = USE_NULL) &#64;javax.annotation.Nonnull(when = When.MAYBE) private Address address;
-	 * </pre>
-	 *
-	 * @author Christoph Strobl
-	 * @see Unwrapped#onEmpty()
-	 */
-	@Unwrapped(onEmpty = OnEmpty.USE_NULL)
-	@Documented
-	@Retention(RetentionPolicy.RUNTIME)
-	@Target({ ElementType.FIELD, ElementType.METHOD })
-	@javax.annotation.Nonnull(when = When.MAYBE)
-	@interface Nullable {
-
-		/**
-		 * @return prefix for columns in the unwrapped value object. An empty {@link String} by default.
-		 */
-		@AliasFor(annotation = Unwrapped.class, attribute = "prefix")
-		String prefix() default "";
-
-		/**
-		 * @return value for columns in the unwrapped value object. An empty {@link String} by default.
-		 */
-		@AliasFor(annotation = Unwrapped.class, attribute = "prefix")
-		String value() default "";
-	}
-
-	/**
-	 * Shortcut for an empty unwrapped property.
-	 *
-	 * <pre class="code">
-	 * &#64;Unwrapped.Empty private Address address;
-	 * </pre>
-	 *
-	 * as alternative to the more verbose
-	 *
-	 * <pre class="code">
-	 * &#64;Unwrapped(onEmpty = USE_EMPTY) &#64;javax.annotation.Nonnull(when = When.NEVER) private Address address;
-	 * </pre>
-	 *
-	 * @author Christoph Strobl
-	 * @see Unwrapped#onEmpty()
-	 */
-	@Unwrapped(onEmpty = OnEmpty.USE_EMPTY)
-	@Documented
-	@Retention(RetentionPolicy.RUNTIME)
-	@Target({ ElementType.FIELD, ElementType.METHOD })
-	@javax.annotation.Nonnull(when = When.NEVER)
-	@interface Empty {
-
-		/**
-		 * @return prefix for columns in the unwrapped value object. An empty {@link String} by default.
-		 */
-		@AliasFor(annotation = Unwrapped.class, attribute = "prefix")
-		String prefix() default "";
-
-		/**
-		 * @return value for columns in the unwrapped value object. An empty {@link String} by default.
-		 */
-		@AliasFor(annotation = Unwrapped.class, attribute = "prefix")
-		String value() default "";
-	}
-}

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/mapping/UnwrappedMongoPersistentEntity.java

@@ -1,326 +0,0 @@
-/*
- * Copyright 2021 the original author or authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      https://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.springframework.data.mongodb.core.mapping;
-
-import java.lang.annotation.Annotation;
-import java.util.ArrayList;
-import java.util.Iterator;
-import java.util.List;
-import java.util.Spliterator;
-import java.util.function.Consumer;
-import java.util.stream.Collectors;
-
-import org.springframework.data.mapping.*;
-import org.springframework.data.mapping.model.PersistentPropertyAccessorFactory;
-import org.springframework.data.mongodb.core.query.Collation;
-import org.springframework.data.spel.EvaluationContextProvider;
-import org.springframework.data.util.Streamable;
-import org.springframework.data.util.TypeInformation;
-import org.springframework.lang.Nullable;
-
-/**
- * Unwrapped variant of {@link MongoPersistentEntity}.
- *
- * @author Christoph Strobl
- * @since 3.2
- * @see Unwrapped
- */
-class UnwrappedMongoPersistentEntity<T> implements MongoPersistentEntity<T> {
-
-	private final UnwrapEntityContext context;
-	private final MongoPersistentEntity<T> delegate;
-
-	public UnwrappedMongoPersistentEntity(MongoPersistentEntity<T> delegate, UnwrapEntityContext context) {
-
-		this.context = context;
-		this.delegate = delegate;
-	}
-
-	@Override
-	public String getCollection() {
-		return delegate.getCollection();
-	}
-
-	@Override
-	public String getLanguage() {
-		return delegate.getLanguage();
-	}
-
-	@Override
-	@Nullable
-	public MongoPersistentProperty getTextScoreProperty() {
-		return delegate.getTextScoreProperty();
-	}
-
-	@Override
-	public boolean hasTextScoreProperty() {
-		return delegate.hasTextScoreProperty();
-	}
-
-	@Override
-	@Nullable
-	public Collation getCollation() {
-		return delegate.getCollation();
-	}
-
-	@Override
-	public boolean hasCollation() {
-		return delegate.hasCollation();
-	}
-
-	@Override
-	public ShardKey getShardKey() {
-		return delegate.getShardKey();
-	}
-
-	@Override
-	public boolean isSharded() {
-		return delegate.isSharded();
-	}
-
-	@Override
-	public String getName() {
-		return delegate.getName();
-	}
-
-	@Override
-	@Nullable
-	public PreferredConstructor<T, MongoPersistentProperty> getPersistenceConstructor() {
-		return delegate.getPersistenceConstructor();
-	}
-
-	@Override
-	public boolean isConstructorArgument(PersistentProperty<?> property) {
-		return delegate.isConstructorArgument(property);
-	}
-
-	@Override
-	public boolean isIdProperty(PersistentProperty<?> property) {
-		return delegate.isIdProperty(property);
-	}
-
-	@Override
-	public boolean isVersionProperty(PersistentProperty<?> property) {
-		return delegate.isVersionProperty(property);
-	}
-
-	@Override
-	@Nullable
-	public MongoPersistentProperty getIdProperty() {
-		return delegate.getIdProperty();
-	}
-
-	@Override
-	public MongoPersistentProperty getRequiredIdProperty() {
-		return delegate.getRequiredIdProperty();
-	}
-
-	@Override
-	@Nullable
-	public MongoPersistentProperty getVersionProperty() {
-		return delegate.getVersionProperty();
-	}
-
-	@Override
-	public MongoPersistentProperty getRequiredVersionProperty() {
-		return delegate.getRequiredVersionProperty();
-	}
-
-	@Override
-	@Nullable
-	public MongoPersistentProperty getPersistentProperty(String name) {
-		return wrap(delegate.getPersistentProperty(name));
-	}
-
-	@Override
-	public MongoPersistentProperty getRequiredPersistentProperty(String name) {
-
-		MongoPersistentProperty persistentProperty = getPersistentProperty(name);
-		if (persistentProperty != null) {
-			return persistentProperty;
-		}
-
-		throw new IllegalStateException(String.format("Required property %s not found for %s!", name, getType()));
-	}
-
-	@Override
-	@Nullable
-	public MongoPersistentProperty getPersistentProperty(Class<? extends Annotation> annotationType) {
-		return wrap(delegate.getPersistentProperty(annotationType));
-	}
-
-	@Override
-	public Iterable<MongoPersistentProperty> getPersistentProperties(Class<? extends Annotation> annotationType) {
-		return Streamable.of(delegate.getPersistentProperties(annotationType)).stream().map(this::wrap)
-				.collect(Collectors.toList());
-	}
-
-	@Override
-	public boolean hasIdProperty() {
-		return delegate.hasIdProperty();
-	}
-
-	@Override
-	public boolean hasVersionProperty() {
-		return delegate.hasVersionProperty();
-	}
-
-	@Override
-	public Class<T> getType() {
-		return delegate.getType();
-	}
-
-	@Override
-	public Alias getTypeAlias() {
-		return delegate.getTypeAlias();
-	}
-
-	@Override
-	public TypeInformation<T> getTypeInformation() {
-		return delegate.getTypeInformation();
-	}
-
-	@Override
-	public void doWithProperties(PropertyHandler<MongoPersistentProperty> handler) {
-
-		delegate.doWithProperties((PropertyHandler<MongoPersistentProperty>) property -> {
-			handler.doWithPersistentProperty(wrap(property));
-		});
-	}
-
-	@Override
-	public void doWithProperties(SimplePropertyHandler handler) {
-
-		delegate.doWithProperties((SimplePropertyHandler) property -> {
-			if (property instanceof MongoPersistentProperty) {
-				handler.doWithPersistentProperty(wrap((MongoPersistentProperty) property));
-			} else {
-				handler.doWithPersistentProperty(property);
-			}
-		});
-	}
-
-	@Override
-	public void doWithAssociations(AssociationHandler<MongoPersistentProperty> handler) {
-		delegate.doWithAssociations(handler);
-	}
-
-	@Override
-	public void doWithAssociations(SimpleAssociationHandler handler) {
-		delegate.doWithAssociations(handler);
-	}
-
-	@Override
-	@Nullable
-	public <A extends Annotation> A findAnnotation(Class<A> annotationType) {
-		return delegate.findAnnotation(annotationType);
-	}
-
-	@Override
-	public <A extends Annotation> A getRequiredAnnotation(Class<A> annotationType) throws IllegalStateException {
-		return delegate.getRequiredAnnotation(annotationType);
-	}
-
-	@Override
-	public <A extends Annotation> boolean isAnnotationPresent(Class<A> annotationType) {
-		return delegate.isAnnotationPresent(annotationType);
-	}
-
-	@Override
-	public <B> PersistentPropertyAccessor<B> getPropertyAccessor(B bean) {
-		return delegate.getPropertyAccessor(bean);
-	}
-
-	@Override
-	public <B> PersistentPropertyPathAccessor<B> getPropertyPathAccessor(B bean) {
-		return delegate.getPropertyPathAccessor(bean);
-	}
-
-	@Override
-	public IdentifierAccessor getIdentifierAccessor(Object bean) {
-		return delegate.getIdentifierAccessor(bean);
-	}
-
-	@Override
-	public boolean isNew(Object bean) {
-		return delegate.isNew(bean);
-	}
-
-	@Override
-	public boolean isImmutable() {
-		return delegate.isImmutable();
-	}
-
-	@Override
-	public boolean requiresPropertyPopulation() {
-		return delegate.requiresPropertyPopulation();
-	}
-
-	@Override
-	public Iterator<MongoPersistentProperty> iterator() {
-
-		List<MongoPersistentProperty> target = new ArrayList<>();
-		delegate.iterator().forEachRemaining(it -> target.add(wrap(it)));
-		return target.iterator();
-	}
-
-	@Override
-	public void forEach(Consumer<? super MongoPersistentProperty> action) {
-		delegate.forEach(it -> action.accept(wrap(it)));
-	}
-
-	@Override
-	public Spliterator<MongoPersistentProperty> spliterator() {
-		return delegate.spliterator();
-	}
-
-	private MongoPersistentProperty wrap(MongoPersistentProperty source) {
-		if (source == null) {
-			return source;
-		}
-		return new UnwrappedMongoPersistentProperty(source, context);
-	}
-
-	@Override
-	public void addPersistentProperty(MongoPersistentProperty property) {
-
-	}
-
-	@Override
-	public void addAssociation(Association<MongoPersistentProperty> association) {
-
-	}
-
-	@Override
-	public void verify() throws MappingException {
-
-	}
-
-	@Override
-	public void setPersistentPropertyAccessorFactory(PersistentPropertyAccessorFactory factory) {
-
-	}
-
-	@Override
-	public void setEvaluationContextProvider(EvaluationContextProvider provider) {
-
-	}
-
-	@Override
-	public boolean isUnwrapped() {
-		return context.getProperty().isUnwrapped();
-	}
-}

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/mapping/UnwrappedMongoPersistentProperty.java

@@ -1,369 +0,0 @@
-/*
- * Copyright 2021 the original author or authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      https://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.springframework.data.mongodb.core.mapping;
-
-import java.lang.annotation.Annotation;
-import java.lang.reflect.Field;
-import java.lang.reflect.Method;
-
-import org.springframework.data.mapping.Association;
-import org.springframework.data.mapping.PersistentEntity;
-import org.springframework.data.mapping.PersistentPropertyAccessor;
-import org.springframework.data.util.TypeInformation;
-import org.springframework.lang.Nullable;
-import org.springframework.util.ObjectUtils;
-
-/**
- * Unwrapped variant of {@link MongoPersistentProperty}.
- *
- * @author Christoph Strobl
- * @author Rogério Meneguelli Gatto
- * @since 3.2
- * @see Unwrapped
- */
-class UnwrappedMongoPersistentProperty implements MongoPersistentProperty {
-
-	private final MongoPersistentProperty delegate;
-	private final UnwrapEntityContext context;
-
-	public UnwrappedMongoPersistentProperty(MongoPersistentProperty delegate, UnwrapEntityContext context) {
-
-		this.delegate = delegate;
-		this.context = context;
-	}
-
-	@Override
-	public String getFieldName() {
-
-		if (!context.getProperty().isUnwrapped()) {
-			return delegate.getFieldName();
-		}
-
-		return context.getProperty().findAnnotation(Unwrapped.class).prefix() + delegate.getFieldName();
-	}
-
-	@Override
-	public Class<?> getFieldType() {
-		return delegate.getFieldType();
-	}
-
-	@Override
-	public int getFieldOrder() {
-		return delegate.getFieldOrder();
-	}
-
-	@Override
-	public boolean writeNullValues() {
-		return delegate.writeNullValues();
-	}
-
-	@Override
-	public boolean isDbReference() {
-		return delegate.isDbReference();
-	}
-
-	@Override
-	public boolean isDocumentReference() {
-		return delegate.isDocumentReference();
-	}
-
-	@Override
-	public boolean isExplicitIdProperty() {
-		return delegate.isExplicitIdProperty();
-	}
-
-	@Override
-	public boolean isLanguageProperty() {
-		return delegate.isLanguageProperty();
-	}
-
-	@Override
-	public boolean isExplicitLanguageProperty() {
-		return delegate.isExplicitLanguageProperty();
-	}
-
-	@Override
-	public boolean isTextScoreProperty() {
-		return delegate.isTextScoreProperty();
-	}
-
-	@Override
-	@Nullable
-	public DBRef getDBRef() {
-		return delegate.getDBRef();
-	}
-
-	@Override
-	@Nullable
-	public DocumentReference getDocumentReference() {
-		return delegate.getDocumentReference();
-	}
-
-	@Override
-	public boolean usePropertyAccess() {
-		return delegate.usePropertyAccess();
-	}
-
-	@Override
-	public boolean hasExplicitWriteTarget() {
-		return delegate.hasExplicitWriteTarget();
-	}
-
-	@Override
-	public PersistentEntity<?, MongoPersistentProperty> getOwner() {
-		return delegate.getOwner();
-	}
-
-	@Override
-	public String getName() {
-		return delegate.getName();
-	}
-
-	@Override
-	public Class<?> getType() {
-		return delegate.getType();
-	}
-
-	@Override
-	public TypeInformation<?> getTypeInformation() {
-		return delegate.getTypeInformation();
-	}
-
-	@Override
-	public Iterable<? extends TypeInformation<?>> getPersistentEntityTypes() {
-		return delegate.getPersistentEntityTypes();
-	}
-
-	@Override
-	public Iterable<? extends TypeInformation<?>> getPersistentEntityTypeInformation() {
-		return delegate.getPersistentEntityTypeInformation();
-	}
-
-	@Override
-	@Nullable
-	public Method getGetter() {
-		return delegate.getGetter();
-	}
-
-	@Override
-	public Method getRequiredGetter() {
-		return delegate.getRequiredGetter();
-	}
-
-	@Override
-	@Nullable
-	public Method getSetter() {
-		return delegate.getSetter();
-	}
-
-	@Override
-	public Method getRequiredSetter() {
-		return delegate.getRequiredSetter();
-	}
-
-	@Override
-	@Nullable
-	public Method getWither() {
-		return delegate.getWither();
-	}
-
-	@Override
-	public Method getRequiredWither() {
-		return delegate.getRequiredWither();
-	}
-
-	@Override
-	@Nullable
-	public Field getField() {
-		return delegate.getField();
-	}
-
-	@Override
-	public Field getRequiredField() {
-		return delegate.getRequiredField();
-	}
-
-	@Override
-	@Nullable
-	public String getSpelExpression() {
-		return delegate.getSpelExpression();
-	}
-
-	@Override
-	@Nullable
-	public Association<MongoPersistentProperty> getAssociation() {
-		return delegate.getAssociation();
-	}
-
-	@Override
-	public Association<MongoPersistentProperty> getRequiredAssociation() {
-		return delegate.getRequiredAssociation();
-	}
-
-	@Override
-	public boolean isEntity() {
-		return delegate.isEntity();
-	}
-
-	@Override
-	public boolean isIdProperty() {
-		return delegate.isIdProperty();
-	}
-
-	@Override
-	public boolean isVersionProperty() {
-		return delegate.isVersionProperty();
-	}
-
-	@Override
-	public boolean isCollectionLike() {
-		return delegate.isCollectionLike();
-	}
-
-	@Override
-	public boolean isMap() {
-		return delegate.isMap();
-	}
-
-	@Override
-	public boolean isArray() {
-		return delegate.isArray();
-	}
-
-	@Override
-	public boolean isTransient() {
-		return delegate.isTransient();
-	}
-
-	@Override
-	public boolean isWritable() {
-		return delegate.isWritable();
-	}
-
-	@Override
-	public boolean isImmutable() {
-		return delegate.isImmutable();
-	}
-
-	@Override
-	public boolean isAssociation() {
-		return delegate.isAssociation();
-	}
-
-	@Override
-	public boolean isUnwrapped() {
-		return delegate.isUnwrapped();
-	}
-
-	@Override
-	@Nullable
-	public Class<?> getComponentType() {
-		return delegate.getComponentType();
-	}
-
-	@Override
-	public Class<?> getRawType() {
-		return delegate.getRawType();
-	}
-
-	@Override
-	@Nullable
-	public Class<?> getMapValueType() {
-		return delegate.getMapValueType();
-	}
-
-	@Override
-	public Class<?> getActualType() {
-		return delegate.getActualType();
-	}
-
-	@Override
-	@Nullable
-	public <A extends Annotation> A findAnnotation(Class<A> annotationType) {
-		return delegate.findAnnotation(annotationType);
-	}
-
-	@Override
-	public <A extends Annotation> A getRequiredAnnotation(Class<A> annotationType) throws IllegalStateException {
-		return delegate.getRequiredAnnotation(annotationType);
-	}
-
-	@Override
-	@Nullable
-	public <A extends Annotation> A findPropertyOrOwnerAnnotation(Class<A> annotationType) {
-		return delegate.findPropertyOrOwnerAnnotation(annotationType);
-	}
-
-	@Override
-	public boolean isAnnotationPresent(Class<? extends Annotation> annotationType) {
-		return delegate.isAnnotationPresent(annotationType);
-	}
-
-	@Override
-	public boolean hasActualTypeAnnotation(Class<? extends Annotation> annotationType) {
-		return delegate.hasActualTypeAnnotation(annotationType);
-	}
-
-	@Override
-	@Nullable
-	public Class<?> getAssociationTargetType() {
-		return delegate.getAssociationTargetType();
-	}
-
-	@Override
-	public TypeInformation<?> getAssociationTargetTypeInformation() {
-		return delegate.getAssociationTargetTypeInformation();
-	}
-
-	@Override
-	public <T> PersistentPropertyAccessor<T> getAccessorForOwner(T owner) {
-		return delegate.getAccessorForOwner(owner);
-	}
-
-	/*
-	 * (non-Javadoc)
-	 * @see java.lang.Object#equals(java.lang.Object)
-	 */
-	@Override
-	public boolean equals(Object obj) {
-
-		if (this == obj) {
-			return true;
-		}
-
-		if (obj == null || getClass() != obj.getClass()) {
-			return false;
-		}
-
-		UnwrappedMongoPersistentProperty that = (UnwrappedMongoPersistentProperty) obj;
-		if (!ObjectUtils.nullSafeEquals(delegate, that.delegate)) {
-			return false;
-		}
-		return ObjectUtils.nullSafeEquals(context, that.context);
-	}
-
-	/*
-	 * (non-Javadoc)
-	 * @see java.lang.Object#hashCode()
-	 */
-	@Override
-	public int hashCode() {
-
-		int result = ObjectUtils.nullSafeHashCode(delegate);
-		result = 31 * result + ObjectUtils.nullSafeHashCode(context);
-		return result;
-	}
-}

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/mapping/event/MongoMappingEvent.java

@@ -77,7 +77,7 @@ public class MongoMappingEvent<T> extends ApplicationEvent {
 
 	/**
 	 * Allows client code to change the underlying source instance by applying the given {@link Function}.
-	 * 
+	 *
 	 * @param mapper the {@link Function} to apply, will only be applied if the source is not {@literal null}.
 	 * @since 2.1
 	 */

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/query/Criteria.java

@@ -29,7 +29,6 @@ import java.util.regex.Pattern;
 import java.util.stream.Collectors;
 
 import org.bson.BsonRegularExpression;
-import org.bson.BsonType;
 import org.bson.Document;
 import org.bson.types.Binary;
 import org.springframework.data.domain.Example;
@@ -53,7 +52,7 @@ import com.mongodb.BasicDBList;
 
 /**
  * Central class for creating queries. It follows a fluent API style so that you can easily chain together multiple
- * criteria. Static import of the {@link Criteria#where Criteria.where} method improves readability.
+ * criteria. Static import of the 'Criteria.where' method will improve readability.
  *
  * @author Thomas Risberg
  * @author Oliver Gierke
@@ -61,7 +60,6 @@ import com.mongodb.BasicDBList;
  * @author Christoph Strobl
  * @author Mark Paluch
  * @author Andreas Zink
- * @author Ziemowit Stolarczyk
  * @author Clément Petit
  */
 public class Criteria implements CriteriaDefinition {
@@ -189,42 +187,6 @@ public class Criteria implements CriteriaDefinition {
 		return this;
 	}
 
-	/**
-	 * Creates a criterion using {@literal null} equality comparison which matches documents that either contain the item
-	 * field whose value is {@literal null} or that do not contain the item field.
-	 * <p />
-	 * Use {@link #isNullValue()} to only query for documents that contain the field whose value is equal to
-	 * {@link org.bson.BsonType#NULL}. <br />
-	 * Use {@link #exists(boolean)} to query for documents that do (not) contain the field.
-	 *
-	 * @return this.
-	 * @see <a href="https://docs.mongodb.com/manual/tutorial/query-for-null-fields/#equality-filter">Query for Null or
-	 *      Missing Fields: Equality Filter</a>
-	 * @since 3.3
-	 */
-	public Criteria isNull() {
-		return is(null);
-	}
-
-	/**
-	 * Creates a criterion using a {@link org.bson.BsonType} comparison which matches only documents that contain the item
-	 * field whose value is equal to {@link org.bson.BsonType#NULL}.
-	 * <p />
-	 * Use {@link #isNull()} to query for documents that contain the field with a {@literal null} value or do not contain the
-	 * field at all. <br />
-	 * Use {@link #exists(boolean)} to query for documents that do (not) contain the field.
-	 *
-	 * @return this.
-	 * @see <a href="https://docs.mongodb.com/manual/tutorial/query-for-null-fields/#type-check">Query for Null or Missing
-	 *      Fields: Type Check</a>
-	 * @since 3.3
-	 */
-	public Criteria isNullValue() {
-
-		criteria.put("$type", BsonType.NULL.getValue());
-		return this;
-	}
-
 	private boolean lastOperatorWasNot() {
 		return !this.criteria.isEmpty() && "$not".equals(this.criteria.keySet().toArray()[this.criteria.size() - 1]);
 	}
@@ -428,22 +390,7 @@ public class Criteria implements CriteriaDefinition {
 		Assert.notNull(types, "Types must not be null!");
 		Assert.noNullElements(types, "Types must not contain null.");
 
-		return type(Arrays.asList(types));
-	}
-
-	/**
-	 * Creates a criterion using the {@literal $type} operator.
-	 *
-	 * @param types must not be {@literal null}.
-	 * @return this.
-	 * @since 3.2
-	 * @see <a href="https://docs.mongodb.com/manual/reference/operator/query/type/">MongoDB Query operator: $type</a>
-	 */
-	public Criteria type(Collection<Type> types) {
-
-		Assert.notNull(types, "Types must not be null!");
-
-		criteria.put("$type", types.stream().map(Type::value).collect(Collectors.toList()));
+		criteria.put("$type", Arrays.asList(types).stream().map(Type::value).collect(Collectors.toList()));
 		return this;
 	}
 
@@ -724,103 +671,46 @@ public class Criteria implements CriteriaDefinition {
 	}
 
 	/**
-	 * Creates a criteria using the {@code $or} operator for all of the provided criteria.
+	 * Creates an 'or' criteria using the $or operator for all of the provided criteria
+	 * <p>
+	 * Note that mongodb doesn't support an $or operator to be wrapped in a $not operator.
 	 * <p>
-	 * Note that MongoDB doesn't support an {@code $nor} operator to be wrapped in a {@code $not} operator.
 	 *
-	 * @throws IllegalArgumentException if this method follows a {@link #not()} call directly.
+	 * @throws IllegalArgumentException if {@link #orOperator(Criteria...)} follows a not() call directly.
 	 * @param criteria must not be {@literal null}.
 	 * @return this.
 	 */
 	public Criteria orOperator(Criteria... criteria) {
-
-		Assert.notNull(criteria, "Criteria must not be null!");
-
-		return orOperator(Arrays.asList(criteria));
-	}
-
-	/**
-	 * Creates a criteria using the {@code $or} operator for all of the provided criteria.
-	 * <p>
-	 * Note that MongoDB doesn't support an {@code $nor} operator to be wrapped in a {@code $not} operator.
-	 *
-	 * @throws IllegalArgumentException if this method follows a {@link #not()} call directly.
-	 * @param criteria must not be {@literal null}.
-	 * @return this.
-	 * @since 3.2
-	 */
-	public Criteria orOperator(Collection<Criteria> criteria) {
-
-		Assert.notNull(criteria, "Criteria must not be null!");
-
 		BasicDBList bsonList = createCriteriaList(criteria);
 		return registerCriteriaChainElement(new Criteria("$or").is(bsonList));
 	}
 
 	/**
-	 * Creates a criteria using the {@code $nor} operator for all of the provided criteria.
+	 * Creates a 'nor' criteria using the $nor operator for all of the provided criteria.
+	 * <p>
+	 * Note that mongodb doesn't support an $nor operator to be wrapped in a $not operator.
 	 * <p>
-	 * Note that MongoDB doesn't support an {@code $nor} operator to be wrapped in a {@code $not} operator.
 	 *
-	 * @throws IllegalArgumentException if this method follows a {@link #not()} call directly.
+	 * @throws IllegalArgumentException if {@link #norOperator(Criteria...)} follows a not() call directly.
 	 * @param criteria must not be {@literal null}.
 	 * @return this.
 	 */
 	public Criteria norOperator(Criteria... criteria) {
-
-		Assert.notNull(criteria, "Criteria must not be null!");
-
-		return norOperator(Arrays.asList(criteria));
-	}
-
-	/**
-	 * Creates a criteria using the {@code $nor} operator for all of the provided criteria.
-	 * <p>
-	 * Note that MongoDB doesn't support an {@code $nor} operator to be wrapped in a {@code $not} operator.
-	 *
-	 * @throws IllegalArgumentException if this method follows a {@link #not()} call directly.
-	 * @param criteria must not be {@literal null}.
-	 * @return this.
-	 * @since 3.2
-	 */
-	public Criteria norOperator(Collection<Criteria> criteria) {
-
-		Assert.notNull(criteria, "Criteria must not be null!");
-
 		BasicDBList bsonList = createCriteriaList(criteria);
 		return registerCriteriaChainElement(new Criteria("$nor").is(bsonList));
 	}
 
 	/**
-	 * Creates a criteria using the {@code $and} operator for all of the provided criteria.
+	 * Creates an 'and' criteria using the $and operator for all of the provided criteria.
+	 * <p>
+	 * Note that mongodb doesn't support an $and operator to be wrapped in a $not operator.
 	 * <p>
-	 * Note that MongoDB doesn't support an {@code $and} operator to be wrapped in a {@code $not} operator.
 	 *
-	 * @throws IllegalArgumentException if this method follows a {@link #not()} call directly.
+	 * @throws IllegalArgumentException if {@link #andOperator(Criteria...)} follows a not() call directly.
 	 * @param criteria must not be {@literal null}.
 	 * @return this.
 	 */
 	public Criteria andOperator(Criteria... criteria) {
-
-		Assert.notNull(criteria, "Criteria must not be null!");
-
-		return andOperator(Arrays.asList(criteria));
-	}
-
-	/**
-	 * Creates a criteria using the {@code $and} operator for all of the provided criteria.
-	 * <p>
-	 * Note that MongoDB doesn't support an {@code $and} operator to be wrapped in a {@code $not} operator.
-	 *
-	 * @throws IllegalArgumentException if this method follows a {@link #not()} call directly.
-	 * @param criteria must not be {@literal null}.
-	 * @return this.
-	 * @since 3.2
-	 */
-	public Criteria andOperator(Collection<Criteria> criteria) {
-
-		Assert.notNull(criteria, "Criteria must not be null!");
-
 		BasicDBList bsonList = createCriteriaList(criteria);
 		return registerCriteriaChainElement(new Criteria("$and").is(bsonList));
 	}
@@ -914,7 +804,7 @@ public class Criteria implements CriteriaDefinition {
 		return queryCriteria;
 	}
 
-	private BasicDBList createCriteriaList(Collection<Criteria> criteria) {
+	private BasicDBList createCriteriaList(Criteria[] criteria) {
 		BasicDBList bsonList = new BasicDBList();
 		for (Criteria c : criteria) {
 			bsonList.add(c.getCriteriaObject());
@@ -923,13 +813,11 @@ public class Criteria implements CriteriaDefinition {
 	}
 
 	private void setValue(Document document, String key, Object value) {
-
 		Object existing = document.get(key);
-
 		if (existing == null) {
 			document.put(key, value);
 		} else {
-			throw new InvalidMongoDbApiUsageException("Due to limitations of the org.bson.Document, "
+			throw new InvalidMongoDbApiUsageException("Due to limitations of the com.mongodb.BasicDocument, "
 					+ "you can't add a second '" + key + "' expression specified as '" + key + " : " + value + "'. "
 					+ "Criteria already contains '" + key + " : " + existing + "'.");
 		}

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/query/Field.java

@@ -20,7 +20,7 @@ import java.util.Map;
 import java.util.Map.Entry;
 
 import org.bson.Document;
-import org.springframework.data.mongodb.MongoExpression;
+
 import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 import org.springframework.util.ObjectUtils;
@@ -37,7 +37,7 @@ import org.springframework.util.ObjectUtils;
  */
 public class Field {
 
-	private final Map<String, Object> criteria = new HashMap<>();
+	private final Map<String, Integer> criteria = new HashMap<>();
 	private final Map<String, Object> slices = new HashMap<>();
 	private final Map<String, Criteria> elemMatchs = new HashMap<>();
 	private @Nullable String positionKey;
@@ -58,62 +58,6 @@ public class Field {
 		return this;
 	}
 
-	/**
-	 * Project a given {@link MongoExpression} to a {@link FieldProjectionExpression#as(String) field} included in the
-	 * result.
-	 *
-	 * <pre class="code">
-	 *
-	 * // { 'name' : { '$toUpper' : '$name' } }
-	 *
-	 * // native MongoDB expression
-	 * .project(MongoExpression.expressionFromString("'$toUpper' : '$name'")).as("name");
-	 *
-	 * // Aggregation Framework expression
-	 * .project(StringOperators.valueOf("name").toUpper()).as("name");
-	 *
-	 * // Aggregation Framework SpEL expression
-	 * .project(AggregationSpELExpression.expressionOf("toUpper(name)")).as("name");
-	 * </pre>
-	 *
-	 * @param expression must not be {@literal null}.
-	 * @return new instance of {@link FieldProjectionExpression}. Define the target field name through
-	 *         {@link FieldProjectionExpression#as(String) as(String)}.
-	 * @since 3.2
-	 */
-	public FieldProjectionExpression project(MongoExpression expression) {
-		return field -> Field.this.projectAs(expression, field);
-	}
-
-	/**
-	 * Project a given {@link MongoExpression} to a {@link FieldProjectionExpression#as(String) field} included in the
-	 * result.
-	 *
-	 * <pre class="code">
-	 *
-	 * // { 'name' : { '$toUpper' : '$name' } }
-	 *
-	 * // native MongoDB expression
-	 * .projectAs(MongoExpression.expressionFromString("'$toUpper' : '$name'"), "name");
-	 *
-	 * // Aggregation Framework expression
-	 * .projectAs(StringOperators.valueOf("name").toUpper(), "name");
-	 *
-	 * // Aggregation Framework SpEL expression
-	 * .projectAs(AggregationSpELExpression.expressionOf("toUpper(name)"), "name");
-	 * </pre>
-	 *
-	 * @param expression must not be {@literal null}.
-	 * @param field the field name used in the result.
-	 * @return new instance of {@link FieldProjectionExpression}.
-	 * @since 3.2
-	 */
-	public Field projectAs(MongoExpression expression, String field) {
-
-		criteria.put(field, expression);
-		return this;
-	}
-
 	/**
 	 * Include one or more {@code fields} to be returned by the query operation.
 	 *
@@ -222,7 +166,8 @@ public class Field {
 
 	public Document getFieldsObject() {
 
-		Document document = new Document(criteria);
+		@SuppressWarnings({ "unchecked", "rawtypes" })
+		Document document = new Document((Map) criteria);
 
 		for (Entry<String, Object> entry : slices.entrySet()) {
 			document.put(entry.getKey(), new Document("$slice", entry.getValue()));
@@ -274,21 +219,4 @@ public class Field {
 		result = 31 * result + positionValue;
 		return result;
 	}
-
-	/**
-	 * Intermediate builder part for projecting a {@link MongoExpression} to a result field.
-	 *
-	 * @since 3.2
-	 * @author Christoph Strobl
-	 */
-	public interface FieldProjectionExpression {
-
-		/**
-		 * Set the name to be used in the result and return a {@link Field}.
-		 *
-		 * @param name must not be {@literal null}.
-		 * @return the calling instance {@link Field}.
-		 */
-		Field as(String name);
-	}
 }

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/query/Meta.java

@@ -181,11 +181,7 @@ public class Meta {
 	}
 
 	/**
-	 * Enables writing to temporary files for aggregation stages and queries. When set to {@literal true}, aggregation
-	 * stages can write data to the {@code _tmp} subdirectory in the {@code dbPath} directory.
-	 * <p>
-	 * Starting in MongoDB 4.2, the profiler log messages and diagnostic log messages includes a {@code usedDisk}
-	 * indicator if any aggregation stage wrote data to temporary files due to memory restrictions.
+	 * Set to {@literal true}, to allow aggregation stages to write data to disk.
 	 *
 	 * @param allowDiskUse use {@literal null} for server defaults.
 	 * @since 3.0

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/query/Query.java

@@ -46,7 +46,6 @@ import org.springframework.util.Assert;
  * @author Thomas Darimont
  * @author Christoph Strobl
  * @author Mark Paluch
- * @author Anton Barkan
  */
 public class Query {
 
@@ -373,24 +372,6 @@ public class Query {
 		return this;
 	}
 
-	/**
-	 * Enables writing to temporary files for aggregation stages and queries. When set to {@literal true}, aggregation
-	 * stages can write data to the {@code _tmp} subdirectory in the {@code dbPath} directory.
-	 * <p>
-	 * Starting in MongoDB 4.2, the profiler log messages and diagnostic log messages includes a {@code usedDisk}
-	 * indicator if any aggregation stage wrote data to temporary files due to memory restrictions.
-	 *
-	 * @param allowDiskUse
-	 * @return this.
-	 * @see Meta#setAllowDiskUse(Boolean)
-	 * @since 3.2
-	 */
-	public Query allowDiskUse(boolean allowDiskUse) {
-
-		meta.setAllowDiskUse(allowDiskUse);
-		return this;
-	}
-
 	/**
 	 * Set the number of documents to return in each response batch. <br />
 	 * Use {@literal 0 (zero)} for no limit. A <strong>negative limit</strong> closes the cursor after returning a single

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/timeseries/GranularityDefinition.java

@@ -1,27 +0,0 @@
-/*
- * Copyright 2021 the original author or authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      https://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.springframework.data.mongodb.core.timeseries;
-
-/**
- * The Granularity of time series data that is closest to the time span between incoming measurements.
- *
- * @author Christoph Strobl
- * @since 3.3
- */
-public interface GranularityDefinition {
-
-	String name();
-}

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/repository/query/AggregationUtils.java

@@ -18,8 +18,6 @@ package org.springframework.data.mongodb.repository.query;
 import java.time.Duration;
 import java.util.List;
 import java.util.Map;
-import java.util.function.IntUnaryOperator;
-import java.util.function.LongUnaryOperator;
 
 import org.bson.Document;
 import org.springframework.data.domain.Pageable;
@@ -44,7 +42,6 @@ import org.springframework.util.StringUtils;
  *
  * @author Christoph Strobl
  * @author Mark Paluch
- * @author Divya Srivastava
  * @since 2.2
  */
 abstract class AggregationUtils {
@@ -136,22 +133,6 @@ abstract class AggregationUtils {
 	 */
 	static void appendLimitAndOffsetIfPresent(List<AggregationOperation> aggregationPipeline,
 			ConvertingParameterAccessor accessor) {
-		appendLimitAndOffsetIfPresent(aggregationPipeline, accessor, LongUnaryOperator.identity(),
-				IntUnaryOperator.identity());
-	}
-
-	/**
-	 * Append {@code $skip} and {@code $limit} aggregation stage if {@link ConvertingParameterAccessor#getSort()} is
-	 * present.
-	 *
-	 * @param aggregationPipeline
-	 * @param accessor
-	 * @param offsetOperator
-	 * @param limitOperator
-	 * @since 3.3
-	 */
-	static void appendLimitAndOffsetIfPresent(List<AggregationOperation> aggregationPipeline,
-			ConvertingParameterAccessor accessor, LongUnaryOperator offsetOperator, IntUnaryOperator limitOperator) {
 
 		Pageable pageable = accessor.getPageable();
 		if (pageable.isUnpaged()) {
@@ -159,10 +140,10 @@ abstract class AggregationUtils {
 		}
 
 		if (pageable.getOffset() > 0) {
-			aggregationPipeline.add(Aggregation.skip(offsetOperator.applyAsLong(pageable.getOffset())));
+			aggregationPipeline.add(Aggregation.skip(pageable.getOffset()));
 		}
 
-		aggregationPipeline.add(Aggregation.limit(limitOperator.applyAsInt(pageable.getPageSize())));
+		aggregationPipeline.add(Aggregation.limit(pageable.getPageSize()));
 	}
 
 	/**

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/repository/query/StringBasedAggregation.java

@@ -17,13 +17,9 @@ package org.springframework.data.mongodb.repository.query;
 
 import java.util.ArrayList;
 import java.util.List;
-import java.util.function.LongUnaryOperator;
-import java.util.stream.Stream;
+import java.util.stream.Collectors;
 
 import org.bson.Document;
-
-import org.springframework.data.domain.Pageable;
-import org.springframework.data.domain.SliceImpl;
 import org.springframework.data.mapping.model.SpELExpressionEvaluator;
 import org.springframework.data.mongodb.InvalidMongoDbApiUsageException;
 import org.springframework.data.mongodb.core.MongoOperations;
@@ -44,12 +40,7 @@ import org.springframework.expression.ExpressionParser;
 import org.springframework.util.ClassUtils;
 
 /**
- * {@link AbstractMongoQuery} implementation to run string-based aggregations using
- * {@link org.springframework.data.mongodb.repository.Aggregation}.
- *
  * @author Christoph Strobl
- * @author Divya Srivastava
- * @author Mark Paluch
  * @since 2.2
  */
 public class StringBasedAggregation extends AbstractMongoQuery {
@@ -71,12 +62,6 @@ public class StringBasedAggregation extends AbstractMongoQuery {
 			ExpressionParser expressionParser, QueryMethodEvaluationContextProvider evaluationContextProvider) {
 		super(method, mongoOperations, expressionParser, evaluationContextProvider);
 
-		if (method.isPageQuery()) {
-			throw new InvalidMongoDbApiUsageException(String.format(
-					"Repository aggregation method '%s' does not support '%s' return type. Please use 'Slice' or 'List' instead.",
-					method.getName(), method.getReturnType().getType().getSimpleName()));
-		}
-
 		this.mongoOperations = mongoOperations;
 		this.mongoConverter = mongoOperations.getConverter();
 		this.expressionParser = expressionParser;
@@ -91,18 +76,18 @@ public class StringBasedAggregation extends AbstractMongoQuery {
 	protected Object doExecute(MongoQueryMethod method, ResultProcessor resultProcessor,
 			ConvertingParameterAccessor accessor, Class<?> typeToRead) {
 
+		if (method.isPageQuery() || method.isSliceQuery()) {
+			throw new InvalidMongoDbApiUsageException(String.format(
+					"Repository aggregation method '%s' does not support '%s' return type. Please use eg. 'List' instead.",
+					method.getName(), method.getReturnType().getType().getSimpleName()));
+		}
+
 		Class<?> sourceType = method.getDomainClass();
 		Class<?> targetType = typeToRead;
 
 		List<AggregationOperation> pipeline = computePipeline(method, accessor);
 		AggregationUtils.appendSortIfPresent(pipeline, accessor, typeToRead);
-
-		if (method.isSliceQuery()) {
-			AggregationUtils.appendLimitAndOffsetIfPresent(pipeline, accessor, LongUnaryOperator.identity(),
-					limit -> limit + 1);
-		} else {
-			AggregationUtils.appendLimitAndOffsetIfPresent(pipeline, accessor);
-		}
+		AggregationUtils.appendLimitAndOffsetIfPresent(pipeline, accessor);
 
 		boolean isSimpleReturnType = isSimpleReturnType(typeToRead);
 		boolean isRawAggregationResult = ClassUtils.isAssignable(AggregationResults.class, typeToRead);
@@ -110,43 +95,28 @@ public class StringBasedAggregation extends AbstractMongoQuery {
 		if (isSimpleReturnType) {
 			targetType = Document.class;
 		} else if (isRawAggregationResult) {
-
-			// 🙈
 			targetType = method.getReturnType().getRequiredActualType().getRequiredComponentType().getType();
 		}
 
 		AggregationOptions options = computeOptions(method, accessor);
 		TypedAggregation<?> aggregation = new TypedAggregation<>(sourceType, pipeline, options);
 
-		if (method.isStreamQuery()) {
-
-			Stream<?> stream = mongoOperations.aggregateStream(aggregation, targetType).stream();
-
-			if (isSimpleReturnType) {
-				return stream.map(it -> AggregationUtils.extractSimpleTypeResult((Document) it, typeToRead, mongoConverter));
-			}
-
-			return stream;
-		}
-
-		AggregationResults<Object> result = (AggregationResults<Object>) mongoOperations.aggregate(aggregation, targetType);
+		AggregationResults<?> result = mongoOperations.aggregate(aggregation, targetType);
 
 		if (isRawAggregationResult) {
 			return result;
 		}
 
-		List<Object> results = result.getMappedResults();
 		if (method.isCollectionQuery()) {
-			return isSimpleReturnType ? convertResults(typeToRead, results) : results;
-		}
 
-		if (method.isSliceQuery()) {
+			if (isSimpleReturnType) {
 
-			Pageable pageable = accessor.getPageable();
-			int pageSize = pageable.getPageSize();
-			List<Object> resultsToUse = isSimpleReturnType ? convertResults(typeToRead, results) : results;
-			boolean hasNext = resultsToUse.size() > pageSize;
-			return new SliceImpl<>(hasNext ? resultsToUse.subList(0, pageSize) : resultsToUse, pageable, hasNext);
+				return result.getMappedResults().stream()
+						.map(it -> AggregationUtils.extractSimpleTypeResult((Document) it, typeToRead, mongoConverter))
+						.collect(Collectors.toList());
+			}
+
+			return result.getMappedResults();
 		}
 
 		Object uniqueResult = result.getUniqueMappedResult();
@@ -156,17 +126,6 @@ public class StringBasedAggregation extends AbstractMongoQuery {
 				: uniqueResult;
 	}
 
-	private List<Object> convertResults(Class<?> typeToRead, List<Object> mappedResults) {
-
-		List<Object> list = new ArrayList<>(mappedResults.size());
-		for (Object it : mappedResults) {
-			Object extractSimpleTypeResult = AggregationUtils.extractSimpleTypeResult((Document) it, typeToRead,
-					mongoConverter);
-			list.add(extractSimpleTypeResult);
-		}
-		return list;
-	}
-
 	private boolean isSimpleReturnType(Class<?> targetType) {
 		return MongoSimpleTypes.HOLDER.isSimpleType(targetType);
 	}

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/repository/support/IndexEnsuringQueryCreationListener.java

@@ -15,14 +15,12 @@
  */
 package org.springframework.data.mongodb.repository.support;
 
-import java.lang.reflect.Field;
 import java.util.Arrays;
 import java.util.HashSet;
 import java.util.Set;
 
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
-import org.springframework.core.annotation.AnnotatedElementUtils;
 import org.springframework.data.domain.Sort;
 import org.springframework.data.domain.Sort.Direction;
 import org.springframework.data.domain.Sort.Order;
@@ -30,7 +28,6 @@ import org.springframework.data.mongodb.UncategorizedMongoDbException;
 import org.springframework.data.mongodb.core.MongoOperations;
 import org.springframework.data.mongodb.core.index.Index;
 import org.springframework.data.mongodb.core.index.IndexOperationsProvider;
-import org.springframework.data.mongodb.core.mapping.Unwrapped;
 import org.springframework.data.mongodb.core.query.Collation;
 import org.springframework.data.mongodb.repository.query.MongoEntityMetadata;
 import org.springframework.data.mongodb.repository.query.PartTreeMongoQuery;
@@ -39,7 +36,6 @@ import org.springframework.data.repository.query.parser.Part;
 import org.springframework.data.repository.query.parser.Part.Type;
 import org.springframework.data.repository.query.parser.PartTree;
 import org.springframework.util.Assert;
-import org.springframework.util.ReflectionUtils;
 
 import com.mongodb.MongoException;
 
@@ -86,14 +82,9 @@ class IndexEnsuringQueryCreationListener implements QueryCreationListener<PartTr
 		Sort sort = tree.getSort();
 
 		for (Part part : tree.getParts()) {
-
 			if (GEOSPATIAL_TYPES.contains(part.getType())) {
 				return;
 			}
-			if (isIndexOnUnwrappedType(part)) {
-				return;
-			}
-
 			String property = part.getProperty().toDotPath();
 			Direction order = toDirection(sort, property);
 			index.on(property, order);
@@ -116,7 +107,7 @@ class IndexEnsuringQueryCreationListener implements QueryCreationListener<PartTr
 
 		MongoEntityMetadata<?> metadata = query.getQueryMethod().getEntityInformation();
 		try {
-			indexOperationsProvider.indexOps(metadata.getCollectionName(), metadata.getJavaType()).ensureIndex(index);
+			indexOperationsProvider.indexOps(metadata.getCollectionName()).ensureIndex(index);
 		} catch (UncategorizedMongoDbException e) {
 
 			if (e.getCause() instanceof MongoException) {
@@ -138,19 +129,6 @@ class IndexEnsuringQueryCreationListener implements QueryCreationListener<PartTr
 		LOG.debug(String.format("Created %s!", index));
 	}
 
-	public boolean isIndexOnUnwrappedType(Part part) {
-
-		// TODO we could do it for nested fields in the
-		Field field = ReflectionUtils.findField(part.getProperty().getOwningType().getType(),
-				part.getProperty().getSegment());
-
-		if (field == null) {
-			return false;
-		}
-
-		return AnnotatedElementUtils.hasAnnotation(field, Unwrapped.class);
-	}
-
 	private static Direction toDirection(Sort sort, String property) {
 
 		if (sort.isUnsorted()) {

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/repository/support/MongoRepositoryFactory.java

@@ -39,6 +39,7 @@ import org.springframework.data.repository.core.RepositoryInformation;
 import org.springframework.data.repository.core.RepositoryMetadata;
 import org.springframework.data.repository.core.support.RepositoryComposition.RepositoryFragments;
 import org.springframework.data.repository.core.support.RepositoryFactorySupport;
+import org.springframework.data.repository.core.support.RepositoryFragment;
 import org.springframework.data.repository.query.QueryLookupStrategy;
 import org.springframework.data.repository.query.QueryLookupStrategy.Key;
 import org.springframework.data.repository.query.QueryMethodEvaluationContextProvider;
@@ -91,21 +92,8 @@ public class MongoRepositoryFactory extends RepositoryFactorySupport {
 	 */
 	@Override
 	protected RepositoryFragments getRepositoryFragments(RepositoryMetadata metadata) {
-		return getRepositoryFragments(metadata, operations);
-	}
 
-	/**
-	 * Creates {@link RepositoryFragments} based on {@link RepositoryMetadata} to add Mongo-specific extensions. Typically
-	 * adds a {@link QuerydslMongoPredicateExecutor} if the repository interface uses Querydsl.
-	 * <p>
-	 * Can be overridden by subclasses to customize {@link RepositoryFragments}.
-	 *
-	 * @param metadata repository metadata.
-	 * @param operations the MongoDB operations manager.
-	 * @return
-	 * @since 3.2.1
-	 */
-	protected RepositoryFragments getRepositoryFragments(RepositoryMetadata metadata, MongoOperations operations) {
+		RepositoryFragments fragments = RepositoryFragments.empty();
 
 		boolean isQueryDslRepository = QUERY_DSL_PRESENT
 				&& QuerydslPredicateExecutor.class.isAssignableFrom(metadata.getRepositoryInterface());
@@ -117,11 +105,14 @@ public class MongoRepositoryFactory extends RepositoryFactorySupport {
 						"Cannot combine Querydsl and reactive repository support in a single interface");
 			}
 
-			return RepositoryFragments
-					.just(new QuerydslMongoPredicateExecutor<>(getEntityInformation(metadata.getDomainType()), operations));
+			MongoEntityInformation<?, Serializable> entityInformation = getEntityInformation(metadata.getDomainType(),
+					metadata);
+
+			fragments = fragments.append(RepositoryFragment.implemented(
+					getTargetRepositoryViaReflection(QuerydslMongoPredicateExecutor.class, entityInformation, operations)));
 		}
 
-		return RepositoryFragments.empty();
+		return fragments;
 	}
 
 	/*

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/repository/support/MongoRepositoryFactoryBean.java

@@ -90,7 +90,7 @@ public class MongoRepositoryFactoryBean<T extends Repository<S, ID>, S, ID exten
 
 		if (createIndexesForQueryMethods) {
 			factory.addQueryCreationListener(
-					new IndexEnsuringQueryCreationListener((collectionName, javaType) -> operations.indexOps(javaType)));
+					new IndexEnsuringQueryCreationListener(collectionName -> operations.indexOps(collectionName)));
 		}
 
 		return factory;

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/repository/support/MongodbDocumentSerializer.java

@@ -0,0 +1,459 @@
+/*
+ * Copyright 2018-2021 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.data.mongodb.repository.support;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.LinkedHashSet;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.Map;
+import java.util.Queue;
+import java.util.Set;
+import java.util.regex.Pattern;
+
+import org.bson.BsonJavaScript;
+import org.bson.BsonRegularExpression;
+import org.bson.Document;
+import org.bson.types.ObjectId;
+import org.springframework.lang.Nullable;
+import org.springframework.util.Assert;
+
+import com.mongodb.DBRef;
+import com.querydsl.core.types.*;
+import com.querydsl.mongodb.MongodbOps;
+
+/**
+ * <p>
+ * Serializes the given Querydsl query to a Document query for MongoDB.
+ * </p>
+ * <p>
+ * Original implementation source {@link com.querydsl.mongodb.MongodbSerializer} by {@literal The Querydsl Team}
+ * (<a href="http://www.querydsl.com/team">http://www.querydsl.com/team</a>) licensed under the Apache License, Version
+ * 2.0.
+ * </p>
+ * Modified to use {@link Document} instead of {@link com.mongodb.DBObject}, updated nullable types and code format. Use
+ * Bson specific types and add {@link QuerydslMongoOps#NO_MATCH}.
+ *
+ * @author laimw
+ * @author Mark Paluch
+ * @author Christoph Strobl
+ * @author Mikhail Kaduchka
+ * @author Enrique Leon Molina
+ * @since 2.1
+ */
+abstract class MongodbDocumentSerializer implements Visitor<Object, Void> {
+
+	@Nullable
+	Object handle(Expression<?> expression) {
+		return expression.accept(this, null);
+	}
+
+	/**
+	 * Create the MongoDB specific query document.
+	 *
+	 * @param predicate must not be {@literal null}.
+	 * @return empty {@link Document} by default.
+	 */
+	Document toQuery(Predicate predicate) {
+
+		Object value = handle(predicate);
+
+		if (value == null) {
+			return new Document();
+		}
+
+		Assert.isInstanceOf(Document.class, value,
+				() -> String.format("Invalid type. Expected Document but found %s", value.getClass()));
+
+		return (Document) value;
+	}
+
+	/**
+	 * Create the MongoDB specific sort document.
+	 *
+	 * @param orderBys must not be {@literal null}.
+	 * @return empty {@link Document} by default.
+	 */
+	Document toSort(List<OrderSpecifier<?>> orderBys) {
+
+		Document sort = new Document();
+
+		orderBys.forEach(orderSpecifier -> {
+
+			Object key = orderSpecifier.getTarget().accept(this, null);
+
+			Assert.notNull(key, () -> String.format("Mapped sort key for %s must not be null!", orderSpecifier));
+			sort.append(key.toString(), orderSpecifier.getOrder() == Order.ASC ? 1 : -1);
+		});
+
+		return sort;
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see com.querydsl.core.types.Visitor#visit(com.querydsl.core.types.Constant, java.lang.Void)
+	 */
+	@Override
+	public Object visit(Constant<?> expr, Void context) {
+
+		if (!Enum.class.isAssignableFrom(expr.getType())) {
+			return expr.getConstant();
+		}
+
+		@SuppressWarnings("unchecked") // Guarded by previous check
+		Constant<? extends Enum<?>> expectedExpr = (Constant<? extends Enum<?>>) expr;
+		return expectedExpr.getConstant().name();
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see com.querydsl.core.types.Visitor#visit(com.querydsl.core.types.TemplateExpression, java.lang.Void)
+	 */
+	@Override
+	public Object visit(TemplateExpression<?> expr, Void context) {
+		throw new UnsupportedOperationException();
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see com.querydsl.core.types.Visitor#visit(com.querydsl.core.types.FactoryExpression, java.lang.Void)
+	 */
+	@Override
+	public Object visit(FactoryExpression<?> expr, Void context) {
+		throw new UnsupportedOperationException();
+	}
+
+	protected String asDBKey(Operation<?> expr, int index) {
+
+		String key = (String) asDBValue(expr, index);
+
+		Assert.hasText(key, () -> String.format("Mapped key must not be null nor empty for expression %s.", expr));
+		return key;
+	}
+
+	@Nullable
+	protected Object asDBValue(Operation<?> expr, int index) {
+		return expr.getArg(index).accept(this, null);
+	}
+
+	private String regexValue(Operation<?> expr, int index) {
+
+		Object value = expr.getArg(index).accept(this, null);
+
+		Assert.notNull(value, () -> String.format("Regex for %s must not be null.", expr));
+		return Pattern.quote(value.toString());
+	}
+
+	protected Document asDocument(String key, @Nullable Object value) {
+		return new Document(key, value);
+	}
+
+	@SuppressWarnings("unchecked")
+	@Override
+	public Object visit(Operation<?> expr, Void context) {
+
+		Operator op = expr.getOperator();
+		if (op == Ops.EQ) {
+
+			if (expr.getArg(0) instanceof Operation) {
+				Operation<?> lhs = (Operation<?>) expr.getArg(0);
+				if (lhs.getOperator() == Ops.COL_SIZE || lhs.getOperator() == Ops.ARRAY_SIZE) {
+					return asDocument(asDBKey(lhs, 0), asDocument("$size", asDBValue(expr, 1)));
+				} else {
+					throw new UnsupportedOperationException("Illegal operation " + expr);
+				}
+			} else if (expr.getArg(0) instanceof Path) {
+				Path<?> path = (Path<?>) expr.getArg(0);
+				Constant<?> constant = (Constant<?>) expr.getArg(1);
+				return asDocument(asDBKey(expr, 0), convert(path, constant));
+			}
+		} else if (op == Ops.STRING_IS_EMPTY) {
+			return asDocument(asDBKey(expr, 0), "");
+		} else if (op == Ops.AND) {
+
+			Queue<Map<Object, Object>> pendingDocuments = collectConnectorArgs("$and", expr);
+			List<Map<Object, Object>> unmergeableDocuments = new ArrayList<>();
+			List<Map<Object, Object>> generatedDocuments = new ArrayList<>();
+
+			while (!pendingDocuments.isEmpty()) {
+
+				Map<Object, Object> lhs = pendingDocuments.poll();
+
+				for (Map<Object, Object> rhs : pendingDocuments) {
+					Set<Object> lhs2 = new LinkedHashSet<>(lhs.keySet());
+					lhs2.retainAll(rhs.keySet());
+					if (lhs2.isEmpty()) {
+						lhs.putAll(rhs);
+					} else {
+						unmergeableDocuments.add(rhs);
+					}
+				}
+
+				generatedDocuments.add(lhs);
+				pendingDocuments = new LinkedList<>(unmergeableDocuments);
+				unmergeableDocuments = new LinkedList<>();
+			}
+
+			return generatedDocuments.size() == 1 ? generatedDocuments.get(0) : asDocument("$and", generatedDocuments);
+		} else if (op == Ops.NOT) {
+			// Handle the not's child
+			Operation<?> subOperation = (Operation<?>) expr.getArg(0);
+			Operator subOp = subOperation.getOperator();
+			if (subOp == Ops.IN) {
+				return visit(
+						ExpressionUtils.operation(Boolean.class, Ops.NOT_IN, subOperation.getArg(0), subOperation.getArg(1)),
+						context);
+			} else {
+				Document arg = (Document) handle(expr.getArg(0));
+				return negate(arg);
+			}
+
+		} else if (op == Ops.OR) {
+			return asDocument("$or", collectConnectorArgs("$or", expr));
+		} else if (op == Ops.NE) {
+
+			Path<?> path = (Path<?>) expr.getArg(0);
+			Constant<?> constant = (Constant<?>) expr.getArg(1);
+			return asDocument(asDBKey(expr, 0), asDocument("$ne", convert(path, constant)));
+
+		} else if (op == Ops.STARTS_WITH) {
+			return asDocument(asDBKey(expr, 0), new BsonRegularExpression("^" + regexValue(expr, 1)));
+		} else if (op == Ops.STARTS_WITH_IC) {
+			return asDocument(asDBKey(expr, 0), new BsonRegularExpression("^" + regexValue(expr, 1), "i"));
+		} else if (op == Ops.ENDS_WITH) {
+			return asDocument(asDBKey(expr, 0), new BsonRegularExpression(regexValue(expr, 1) + "$"));
+		} else if (op == Ops.ENDS_WITH_IC) {
+			return asDocument(asDBKey(expr, 0), new BsonRegularExpression(regexValue(expr, 1) + "$", "i"));
+		} else if (op == Ops.EQ_IGNORE_CASE) {
+			return asDocument(asDBKey(expr, 0), new BsonRegularExpression("^" + regexValue(expr, 1) + "$", "i"));
+		} else if (op == Ops.STRING_CONTAINS) {
+			return asDocument(asDBKey(expr, 0), new BsonRegularExpression(".*" + regexValue(expr, 1) + ".*"));
+		} else if (op == Ops.STRING_CONTAINS_IC) {
+			return asDocument(asDBKey(expr, 0), new BsonRegularExpression(".*" + regexValue(expr, 1) + ".*", "i"));
+		} else if (op == Ops.MATCHES) {
+			return asDocument(asDBKey(expr, 0), new BsonRegularExpression(asDBValue(expr, 1).toString()));
+		} else if (op == Ops.MATCHES_IC) {
+			return asDocument(asDBKey(expr, 0), new BsonRegularExpression(asDBValue(expr, 1).toString(), "i"));
+		} else if (op == Ops.LIKE) {
+
+			String regex = ExpressionUtils.likeToRegex((Expression) expr.getArg(1)).toString();
+			return asDocument(asDBKey(expr, 0), new BsonRegularExpression(regex));
+		} else if (op == Ops.BETWEEN) {
+
+			Document value = new Document("$gte", asDBValue(expr, 1));
+			value.append("$lte", asDBValue(expr, 2));
+			return asDocument(asDBKey(expr, 0), value);
+		} else if (op == Ops.IN) {
+
+			int constIndex = 0;
+			int exprIndex = 1;
+			if (expr.getArg(1) instanceof Constant<?>) {
+				constIndex = 1;
+				exprIndex = 0;
+			}
+			if (Collection.class.isAssignableFrom(expr.getArg(constIndex).getType())) {
+				@SuppressWarnings("unchecked") // guarded by previous check
+				Collection<?> values = ((Constant<? extends Collection<?>>) expr.getArg(constIndex)).getConstant();
+				return asDocument(asDBKey(expr, exprIndex), asDocument("$in", values));
+			} else {
+				Path<?> path = (Path<?>) expr.getArg(exprIndex);
+				Constant<?> constant = (Constant<?>) expr.getArg(constIndex);
+				return asDocument(asDBKey(expr, exprIndex), convert(path, constant));
+			}
+		} else if (op == Ops.NOT_IN) {
+
+			int constIndex = 0;
+			int exprIndex = 1;
+			if (expr.getArg(1) instanceof Constant<?>) {
+
+				constIndex = 1;
+				exprIndex = 0;
+			}
+			if (Collection.class.isAssignableFrom(expr.getArg(constIndex).getType())) {
+
+				@SuppressWarnings("unchecked") // guarded by previous check
+				Collection<?> values = ((Constant<? extends Collection<?>>) expr.getArg(constIndex)).getConstant();
+				return asDocument(asDBKey(expr, exprIndex), asDocument("$nin", values));
+			} else {
+
+				Path<?> path = (Path<?>) expr.getArg(exprIndex);
+				Constant<?> constant = (Constant<?>) expr.getArg(constIndex);
+				return asDocument(asDBKey(expr, exprIndex), asDocument("$ne", convert(path, constant)));
+			}
+		} else if (op == Ops.COL_IS_EMPTY) {
+
+			List<Object> list = new ArrayList<>(2);
+			list.add(asDocument(asDBKey(expr, 0), new ArrayList<Object>()));
+			list.add(asDocument(asDBKey(expr, 0), asDocument("$exists", false)));
+			return asDocument("$or", list);
+		} else if (op == Ops.LT) {
+			return asDocument(asDBKey(expr, 0), asDocument("$lt", asDBValue(expr, 1)));
+		} else if (op == Ops.GT) {
+			return asDocument(asDBKey(expr, 0), asDocument("$gt", asDBValue(expr, 1)));
+		} else if (op == Ops.LOE) {
+			return asDocument(asDBKey(expr, 0), asDocument("$lte", asDBValue(expr, 1)));
+		} else if (op == Ops.GOE) {
+			return asDocument(asDBKey(expr, 0), asDocument("$gte", asDBValue(expr, 1)));
+		} else if (op == Ops.IS_NULL) {
+			return asDocument(asDBKey(expr, 0), asDocument("$exists", false));
+		} else if (op == Ops.IS_NOT_NULL) {
+			return asDocument(asDBKey(expr, 0), asDocument("$exists", true));
+		} else if (op == Ops.CONTAINS_KEY) {
+
+			Path<?> path = (Path<?>) expr.getArg(0);
+			Expression<?> key = expr.getArg(1);
+			return asDocument(visit(path, context) + "." + key.toString(), asDocument("$exists", true));
+		} else if (op == MongodbOps.NEAR) {
+			return asDocument(asDBKey(expr, 0), asDocument("$near", asDBValue(expr, 1)));
+		} else if (op == MongodbOps.NEAR_SPHERE) {
+			return asDocument(asDBKey(expr, 0), asDocument("$nearSphere", asDBValue(expr, 1)));
+		} else if (op == MongodbOps.ELEM_MATCH) {
+			return asDocument(asDBKey(expr, 0), asDocument("$elemMatch", asDBValue(expr, 1)));
+		} else if (op == QuerydslMongoOps.NO_MATCH) {
+			return new Document("$where", new BsonJavaScript("function() { return false }"));
+		}
+
+		throw new UnsupportedOperationException("Illegal operation " + expr);
+	}
+
+	private Object negate(Document arg) {
+
+		List<Object> list = new ArrayList<>();
+		for (Map.Entry<String, Object> entry : arg.entrySet()) {
+
+			if (entry.getKey().equals("$or")) {
+				list.add(asDocument("$nor", entry.getValue()));
+			} else if (entry.getKey().equals("$and")) {
+
+				List<Object> list2 = new ArrayList<>();
+				for (Object o : ((Collection) entry.getValue())) {
+					list2.add(negate((Document) o));
+				}
+				list.add(asDocument("$or", list2));
+			} else if (entry.getValue() instanceof Pattern || entry.getValue() instanceof BsonRegularExpression) {
+				list.add(asDocument(entry.getKey(), asDocument("$not", entry.getValue())));
+			} else if (entry.getValue() instanceof Document) {
+				list.add(negate(entry.getKey(), (Document) entry.getValue()));
+			} else {
+				list.add(asDocument(entry.getKey(), asDocument("$ne", entry.getValue())));
+			}
+		}
+		return list.size() == 1 ? list.get(0) : asDocument("$or", list);
+	}
+
+	private Object negate(String key, Document value) {
+
+		if (value.size() == 1) {
+			return asDocument(key, asDocument("$not", value));
+		} else {
+
+			List<Object> list2 = new ArrayList<>();
+			for (Map.Entry<String, Object> entry2 : value.entrySet()) {
+				list2.add(asDocument(key, asDocument("$not", asDocument(entry2.getKey(), entry2.getValue()))));
+			}
+
+			return asDocument("$or", list2);
+		}
+	}
+
+	protected Object convert(Path<?> property, Constant<?> constant) {
+
+		if (isReference(property)) {
+			return asReference(constant.getConstant());
+		} else if (isId(property)) {
+
+			if (isReference(property.getMetadata().getParent())) {
+				return asReferenceKey(property.getMetadata().getParent().getType(), constant.getConstant());
+			} else if (constant.getType().equals(String.class) && isImplicitObjectIdConversion()) {
+
+				String id = (String) constant.getConstant();
+				return ObjectId.isValid(id) ? new ObjectId(id) : id;
+			}
+		}
+		return visit(constant, null);
+	}
+
+	protected boolean isImplicitObjectIdConversion() {
+		return true;
+	}
+
+	protected DBRef asReferenceKey(Class<?> entity, Object id) {
+		// TODO override in subclass
+		throw new UnsupportedOperationException();
+	}
+
+	protected abstract DBRef asReference(Object constant);
+
+	protected abstract boolean isReference(@Nullable Path<?> arg);
+
+	protected boolean isId(Path<?> arg) {
+		// TODO override in subclass
+		return false;
+	}
+
+	@Override
+	public String visit(Path<?> expr, Void context) {
+
+		PathMetadata metadata = expr.getMetadata();
+
+		if (metadata.getParent() != null) {
+
+			Path<?> parent = metadata.getParent();
+			if (parent.getMetadata().getPathType() == PathType.DELEGATE) {
+				parent = parent.getMetadata().getParent();
+			}
+			if (metadata.getPathType() == PathType.COLLECTION_ANY) {
+				return visit(parent, context);
+			} else if (parent.getMetadata().getPathType() != PathType.VARIABLE) {
+
+				String rv = getKeyForPath(expr, metadata);
+				String parentStr = visit(parent, context);
+				return rv != null ? parentStr + "." + rv : parentStr;
+			}
+		}
+		return getKeyForPath(expr, metadata);
+	}
+
+	protected String getKeyForPath(Path<?> expr, PathMetadata metadata) {
+		return metadata.getElement().toString();
+	}
+
+	@Override
+	public Object visit(SubQueryExpression<?> expr, Void context) {
+		throw new UnsupportedOperationException();
+	}
+
+	@Override
+	public Object visit(ParamExpression<?> expr, Void context) {
+		throw new UnsupportedOperationException();
+	}
+
+	private LinkedList<Map<Object, Object>> collectConnectorArgs(String operator, Operation<?> operation) {
+
+		LinkedList<Map<Object, Object>> pendingDocuments = new LinkedList<>();
+		for (Expression<?> exp : operation.getArgs()) {
+			Map<Object, Object> document = (Map<Object, Object>) handle(exp);
+			if (document.keySet().size() == 1 && document.containsKey(operator)) {
+				pendingDocuments.addAll((Collection<Map<Object, Object>>) document.get(operator));
+			} else {
+				pendingDocuments.add(document);
+			}
+		}
+		return pendingDocuments;
+
+	}
+}

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/repository/support/QuerydslAbstractMongodbQuery.java

@@ -34,8 +34,6 @@ import com.querydsl.core.types.FactoryExpression;
 import com.querydsl.core.types.OrderSpecifier;
 import com.querydsl.core.types.ParamExpression;
 import com.querydsl.core.types.Predicate;
-import com.querydsl.mongodb.document.AbstractMongodbQuery;
-import com.querydsl.mongodb.document.MongodbDocumentSerializer;
 
 /**
  * {@code QuerydslAbstractMongodbQuery} provides a base class for general Querydsl query implementation.
@@ -51,12 +49,8 @@ import com.querydsl.mongodb.document.MongodbDocumentSerializer;
  * @author Mark Paluch
  * @author Christoph Strobl
  * @since 2.1
- * @deprecated since 3.3, use Querydsl's {@link AbstractMongodbQuery} directly. This class is deprecated for removal
- *             with the next major release.
  */
-@Deprecated
 public abstract class QuerydslAbstractMongodbQuery<K, Q extends QuerydslAbstractMongodbQuery<K, Q>>
-		extends AbstractMongodbQuery<Q>
 		implements SimpleQuery<Q> {
 
 	private static final JsonWriterSettings JSON_WRITER_SETTINGS = JsonWriterSettings.builder().outputMode(JsonMode.SHELL)
@@ -73,8 +67,6 @@ public abstract class QuerydslAbstractMongodbQuery<K, Q extends QuerydslAbstract
 	@SuppressWarnings("unchecked")
 	QuerydslAbstractMongodbQuery(MongodbDocumentSerializer serializer) {
 
-		super(serializer);
-
 		this.queryMixin = new QueryMixin<>((Q) this, new DefaultQueryMetadata(), false);
 		this.serializer = serializer;
 	}
@@ -166,6 +158,22 @@ public abstract class QuerydslAbstractMongodbQuery<K, Q extends QuerydslAbstract
 		return projection;
 	}
 
+	/**
+	 * Compute the filer {@link Document} from the given {@link Predicate}.
+	 *
+	 * @param predicate can be {@literal null}.
+	 * @return an empty {@link Document} if predicate is {@literal null}.
+	 * @see MongodbDocumentSerializer#toQuery(Predicate)
+	 */
+	protected Document createQuery(@Nullable Predicate predicate) {
+
+		if (predicate == null) {
+			return new Document();
+		}
+
+		return serializer.toQuery(predicate);
+	}
+
 	/**
 	 * Compute the sort {@link Document} from the given list of {@link OrderSpecifier order specifiers}.
 	 *
@@ -177,6 +185,24 @@ public abstract class QuerydslAbstractMongodbQuery<K, Q extends QuerydslAbstract
 		return serializer.toSort(orderSpecifiers);
 	}
 
+	/**
+	 * Get the actual {@link QueryMixin} delegate.
+	 *
+	 * @return
+	 */
+	QueryMixin<Q> getQueryMixin() {
+		return queryMixin;
+	}
+
+	/**
+	 * Get the where definition as a Document instance
+	 *
+	 * @return
+	 */
+	Document asDocument() {
+		return createQuery(queryMixin.getMetadata().getWhere());
+	}
+
 	/**
 	 * Returns the {@literal Mongo Shell} representation of the query. <br />
 	 * The following query

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/repository/support/QuerydslAnyEmbeddedBuilder.java

@@ -37,10 +37,7 @@ import com.querydsl.mongodb.MongodbOps;
  * @author Mark Paluch
  * @author Christoph Strobl
  * @since 2.1
- * @deprecated since 3.3, use Querydsl's {@link com.querydsl.mongodb.document.AnyEmbeddedBuilder} directly. This class
- *             is deprecated for removal with the next major release.
  */
-@Deprecated
 public class QuerydslAnyEmbeddedBuilder<Q extends QuerydslAbstractMongodbQuery<K, Q>, K> {
 
 	private final QueryMixin<Q> queryMixin;

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/repository/support/QuerydslFetchableMongodbQuery.java

@@ -0,0 +1,272 @@
+/*
+ * Copyright 2018-2021 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.data.mongodb.repository.support;
+
+import java.util.Collection;
+import java.util.Collections;
+import java.util.List;
+
+import org.springframework.data.mongodb.core.ExecutableFindOperation.FindWithProjection;
+import org.springframework.data.mongodb.core.MongoOperations;
+import org.springframework.data.mongodb.core.query.BasicQuery;
+import org.springframework.data.mongodb.core.query.Query;
+import org.springframework.lang.Nullable;
+import org.springframework.util.LinkedMultiValueMap;
+
+import com.mysema.commons.lang.CloseableIterator;
+import com.querydsl.core.Fetchable;
+import com.querydsl.core.JoinExpression;
+import com.querydsl.core.QueryMetadata;
+import com.querydsl.core.QueryModifiers;
+import com.querydsl.core.QueryResults;
+import com.querydsl.core.types.Expression;
+import com.querydsl.core.types.ExpressionUtils;
+import com.querydsl.core.types.Operation;
+import com.querydsl.core.types.OrderSpecifier;
+import com.querydsl.core.types.Path;
+import com.querydsl.core.types.Predicate;
+import com.querydsl.core.types.dsl.CollectionPathBase;
+
+/**
+ * {@link Fetchable} MongoDB query with utilizing {@link MongoOperations} for command execution.
+ *
+ * @param <K> result type
+ * @param <Q> concrete subtype
+ * @author Mark Paluch
+ * @author Christoph Strobl
+ * @since 2.1
+ */
+abstract class QuerydslFetchableMongodbQuery<K, Q extends QuerydslFetchableMongodbQuery<K, Q>>
+		extends QuerydslAbstractMongodbQuery<K, Q> implements Fetchable<K> {
+
+	private final Class<K> entityClass;
+	private final String collection;
+	private final MongoOperations mongoOperations;
+	private final FindWithProjection<K> find;
+
+	QuerydslFetchableMongodbQuery(MongodbDocumentSerializer serializer, Class<? extends K> entityClass, String collection,
+			MongoOperations mongoOperations) {
+
+		super(serializer);
+
+		this.entityClass = (Class<K>) entityClass;
+		this.collection = collection;
+		this.mongoOperations = mongoOperations;
+		find = mongoOperations.query(this.entityClass).inCollection(collection);
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see com.querydsl.core.Fetchable#iterable()
+	 */
+	@Override
+	public CloseableIterator<K> iterate() {
+
+		org.springframework.data.util.CloseableIterator<? extends K> stream = mongoOperations.stream(createQuery(),
+				entityClass, collection);
+
+		return new CloseableIterator<K>() {
+
+			@Override
+			public boolean hasNext() {
+				return stream.hasNext();
+			}
+
+			@Override
+			public K next() {
+				return stream.next();
+			}
+
+			@Override
+			public void remove() {
+				throw new UnsupportedOperationException("Cannot remove from iterator while streaming data.");
+			}
+
+			@Override
+			public void close() {
+				stream.close();
+			}
+		};
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see com.querydsl.core.Fetchable#fetch()
+	 */
+	@Override
+	public List<K> fetch() {
+		return find.matching(createQuery()).all();
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see com.querydsl.core.Fetchable#fetchFirst()
+	 */
+	@Override
+	public K fetchFirst() {
+		return find.matching(createQuery()).firstValue();
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see com.querydsl.core.Fetchable#fetchOne()
+	 */
+	@Override
+	public K fetchOne() {
+		return find.matching(createQuery()).oneValue();
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see com.querydsl.core.Fetchable#fetchResults()
+	 */
+	@Override
+	public QueryResults<K> fetchResults() {
+
+		long total = fetchCount();
+		return total > 0L ? new QueryResults<>(fetch(), getQueryMixin().getMetadata().getModifiers(), total)
+				: QueryResults.emptyResults();
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see com.querydsl.core.Fetchable#fetchCount()
+	 */
+	@Override
+	public long fetchCount() {
+		return find.matching(Query.of(createQuery()).skip(-1).limit(-1)).count();
+	}
+
+	/**
+	 * Define a join.
+	 *
+	 * @param ref reference
+	 * @param target join target
+	 * @return new instance of {@link QuerydslJoinBuilder}.
+	 */
+	public <T> QuerydslJoinBuilder<Q, K, T> join(Path<T> ref, Path<T> target) {
+		return new QuerydslJoinBuilder<>(getQueryMixin(), ref, target);
+	}
+
+	/**
+	 * Define a join.
+	 *
+	 * @param ref reference
+	 * @param target join target
+	 * @return new instance of {@link QuerydslJoinBuilder}.
+	 */
+	public <T> QuerydslJoinBuilder<Q, K, T> join(CollectionPathBase<?, T, ?> ref, Path<T> target) {
+		return new QuerydslJoinBuilder<>(getQueryMixin(), ref, target);
+	}
+
+	/**
+	 * Define a constraint for an embedded object.
+	 *
+	 * @param collection collection must not be {@literal null}.
+	 * @param target target must not be {@literal null}.
+	 * @return new instance of {@link QuerydslAnyEmbeddedBuilder}.
+	 */
+	public <T> QuerydslAnyEmbeddedBuilder<Q, K> anyEmbedded(Path<? extends Collection<T>> collection, Path<T> target) {
+		return new QuerydslAnyEmbeddedBuilder<>(getQueryMixin(), collection);
+	}
+
+	protected org.springframework.data.mongodb.core.query.Query createQuery() {
+
+		QueryMetadata metadata = getQueryMixin().getMetadata();
+
+		return createQuery(createFilter(metadata), metadata.getProjection(), metadata.getModifiers(),
+				metadata.getOrderBy());
+	}
+
+	protected org.springframework.data.mongodb.core.query.Query createQuery(@Nullable Predicate filter,
+			@Nullable Expression<?> projection, QueryModifiers modifiers, List<OrderSpecifier<?>> orderBy) {
+
+		BasicQuery basicQuery = new BasicQuery(createQuery(filter), createProjection(projection));
+
+		Integer limit = modifiers.getLimitAsInteger();
+		Integer offset = modifiers.getOffsetAsInteger();
+
+		if (limit != null) {
+			basicQuery.limit(limit);
+		}
+		if (offset != null) {
+			basicQuery.skip(offset);
+		}
+		if (orderBy.size() > 0) {
+			basicQuery.setSortObject(createSort(orderBy));
+		}
+
+		return basicQuery;
+	}
+
+	@Nullable
+	protected Predicate createFilter(QueryMetadata metadata) {
+
+		Predicate filter;
+		if (!metadata.getJoins().isEmpty()) {
+			filter = ExpressionUtils.allOf(metadata.getWhere(), createJoinFilter(metadata));
+		} else {
+			filter = metadata.getWhere();
+		}
+		return filter;
+	}
+
+	@SuppressWarnings("unchecked")
+	@Nullable
+	protected Predicate createJoinFilter(QueryMetadata metadata) {
+
+		LinkedMultiValueMap<Expression<?>, Predicate> predicates = new LinkedMultiValueMap<>();
+		List<JoinExpression> joins = metadata.getJoins();
+
+		for (int i = joins.size() - 1; i >= 0; i--) {
+
+			JoinExpression join = joins.get(i);
+			Path<?> source = (Path) ((Operation<?>) join.getTarget()).getArg(0);
+			Path<?> target = (Path) ((Operation<?>) join.getTarget()).getArg(1);
+			Collection<Predicate> extraFilters = predicates.get(target.getRoot());
+			Predicate filter = ExpressionUtils.allOf(join.getCondition(), allOf(extraFilters));
+
+			List<? extends Object> ids = getIds(target.getType(), filter);
+
+			if (ids.isEmpty()) {
+				return ExpressionUtils.predicate(QuerydslMongoOps.NO_MATCH, source);
+			}
+
+			Path<?> path = ExpressionUtils.path(String.class, source, "$id");
+			predicates.add(source.getRoot(), ExpressionUtils.in((Path<Object>) path, ids));
+		}
+
+		Path<?> source = (Path) ((Operation) joins.get(0).getTarget()).getArg(0);
+		return allOf(predicates.get(source.getRoot()));
+	}
+
+	private Predicate allOf(Collection<Predicate> predicates) {
+		return predicates != null ? ExpressionUtils.allOf(predicates) : null;
+	}
+
+	/**
+	 * Fetch the list of ids matching a given condition.
+	 *
+	 * @param targetType must not be {@literal null}.
+	 * @param condition must not be {@literal null}.
+	 * @return empty {@link List} if none found.
+	 */
+	protected List<Object> getIds(Class<?> targetType, Predicate condition) {
+
+		Query query = createQuery(condition, null, QueryModifiers.EMPTY, Collections.emptyList());
+		return mongoOperations.findDistinct(query, "_id", targetType, Object.class);
+	}
+}

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/repository/support/QuerydslJoinBuilder.java

@@ -0,0 +1,67 @@
+/*
+ * Copyright 2018-2021 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.data.mongodb.repository.support;
+
+import com.querydsl.core.JoinType;
+import com.querydsl.core.support.QueryMixin;
+import com.querydsl.core.types.ExpressionUtils;
+import com.querydsl.core.types.Path;
+import com.querydsl.core.types.Predicate;
+
+/**
+ * {@code QuerydslJoinBuilder} is a builder for join constraints.
+ * <p>
+ * Original implementation source {@link com.querydsl.mongodb.JoinBuilder} by {@literal The Querydsl Team}
+ * (<a href="http://www.querydsl.com/team">http://www.querydsl.com/team</a>) licensed under the Apache License, Version
+ * 2.0.
+ * </p>
+ * Modified for usage with {@link QuerydslAbstractMongodbQuery}.
+ *
+ * @param <Q>
+ * @param <T>
+ * @author tiwe
+ * @author Mark Paluch
+ * @author Christoph Strobl
+ * @since 2.1
+ */
+public class QuerydslJoinBuilder<Q extends QuerydslAbstractMongodbQuery<K, Q>, K, T> {
+
+	private final QueryMixin<Q> queryMixin;
+	private final Path<?> ref;
+	private final Path<T> target;
+
+	QuerydslJoinBuilder(QueryMixin<Q> queryMixin, Path<?> ref, Path<T> target) {
+
+		this.queryMixin = queryMixin;
+		this.ref = ref;
+		this.target = target;
+	}
+
+	/**
+	 * Add the given join conditions.
+	 *
+	 * @param conditions must not be {@literal null}.
+	 * @return the target {@link QueryMixin}.
+	 * @see QueryMixin#on(Predicate)
+	 */
+	@SuppressWarnings("unchecked")
+	public Q on(Predicate... conditions) {
+
+		queryMixin.addJoin(JoinType.JOIN, ExpressionUtils.as((Path) ref, target));
+		queryMixin.on(conditions);
+		return queryMixin.getSelf();
+	}
+}

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/repository/support/QuerydslMongoOps.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2021 the original author or authors.
+ * Copyright 2018-2021 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -13,33 +13,31 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-package org.springframework.data.mongodb.core.timeseries;
+package org.springframework.data.mongodb.repository.support;
+
+import com.querydsl.core.types.Operator;
 
 /**
- * {@link GranularityDefinition Granularities} available for Time Series data.
+ * Spring Data specific {@link Operator operators} for usage with Querydsl and MongoDB.
  *
  * @author Christoph Strobl
- * @since 3.3
+ * @since 2.1
  */
-public enum Granularity implements GranularityDefinition {
+enum QuerydslMongoOps implements Operator {
 
 	/**
-	 * Server default value to indicate no explicit value should be sent.
+	 * {@link Operator} always evaluating to {@literal false}.
 	 */
-	DEFAULT,
+	NO_MATCH(Boolean.class);
 
-	/**
-	 * High frequency ingestion.
-	 */
-	SECONDS,
+	private final Class<?> type;
 
-	/**
-	 * Medium frequency ingestion.
-	 */
-	MINUTES,
+	QuerydslMongoOps(Class<?> type) {
+		this.type = type;
+	}
 
-	/**
-	 * Low frequency ingestion.
-	 */
-	HOURS
+	@Override
+	public Class<?> getType() {
+		return type;
+	}
 }

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/repository/support/QuerydslMongoPredicateExecutor.java

@@ -27,7 +27,7 @@ import org.springframework.data.mongodb.repository.query.MongoEntityInformation;
 import org.springframework.data.querydsl.EntityPathResolver;
 import org.springframework.data.querydsl.QuerydslPredicateExecutor;
 import org.springframework.data.querydsl.SimpleEntityPathResolver;
-import org.springframework.data.support.PageableExecutionUtils;
+import org.springframework.data.repository.support.PageableExecutionUtils;
 import org.springframework.util.Assert;
 
 import com.querydsl.core.NonUniqueResultException;

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/repository/support/ReactiveMongoRepositoryFactoryBean.java

@@ -97,7 +97,7 @@ public class ReactiveMongoRepositoryFactoryBean<T extends Repository<S, ID>, S,
 
 		if (createIndexesForQueryMethods) {
 			factory.addQueryCreationListener(new IndexEnsuringQueryCreationListener(
-					(collectionName, javaType) -> IndexOperationsAdapter.blocking(operations.indexOps(javaType))));
+					collectionName -> IndexOperationsAdapter.blocking(operations.indexOps(collectionName))));
 		}
 
 		return factory;

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/repository/support/ReactiveSpringDataMongodbQuery.java

@@ -22,9 +22,6 @@ import java.util.Collection;
 import java.util.Collections;
 import java.util.List;
 
-import org.bson.Document;
-
-import org.springframework.data.mongodb.core.MongoOperations;
 import org.springframework.data.mongodb.core.ReactiveFindOperation.FindWithProjection;
 import org.springframework.data.mongodb.core.ReactiveMongoOperations;
 import org.springframework.data.mongodb.core.query.BasicQuery;
@@ -43,21 +40,19 @@ import com.querydsl.core.types.Operation;
 import com.querydsl.core.types.OrderSpecifier;
 import com.querydsl.core.types.Path;
 import com.querydsl.core.types.Predicate;
-import com.querydsl.mongodb.MongodbOps;
-import com.querydsl.mongodb.document.MongodbDocumentSerializer;
+import com.querydsl.core.types.dsl.CollectionPathBase;
 
 /**
  * MongoDB query with utilizing {@link ReactiveMongoOperations} for command execution.
  *
- * @implNote This class uses {@link MongoOperations} to directly convert documents into the target entity type. Also, we
- *           want entites to participate in lifecycle events and entity callbacks.
  * @param <K> result type
  * @author Mark Paluch
  * @author Christoph Strobl
  * @since 2.2
  */
-class ReactiveSpringDataMongodbQuery<K> extends SpringDataMongodbQuerySupport<ReactiveSpringDataMongodbQuery<K>> {
+class ReactiveSpringDataMongodbQuery<K> extends QuerydslAbstractMongodbQuery<K, ReactiveSpringDataMongodbQuery<K>> {
 
+	private final Class<K> entityClass;
 	private final ReactiveMongoOperations mongoOperations;
 	private final FindWithProjection<K> find;
 
@@ -65,15 +60,15 @@ class ReactiveSpringDataMongodbQuery<K> extends SpringDataMongodbQuerySupport<Re
 		this(new SpringDataMongodbSerializer(mongoOperations.getConverter()), mongoOperations, entityClass, null);
 	}
 
-	@SuppressWarnings("unchecked")
 	ReactiveSpringDataMongodbQuery(MongodbDocumentSerializer serializer, ReactiveMongoOperations mongoOperations,
 			Class<? extends K> entityClass, @Nullable String collection) {
 
 		super(serializer);
 
+		this.entityClass = (Class<K>) entityClass;
 		this.mongoOperations = mongoOperations;
-		this.find = StringUtils.hasText(collection) ? mongoOperations.query((Class<K>) entityClass).inCollection(collection)
-				: mongoOperations.query((Class<K>) entityClass);
+		this.find = StringUtils.hasText(collection) ? mongoOperations.query(this.entityClass).inCollection(collection)
+				: mongoOperations.query(this.entityClass);
 	}
 
 	/**
@@ -104,11 +99,48 @@ class ReactiveSpringDataMongodbQuery<K> extends SpringDataMongodbQuerySupport<Re
 		return createQuery().flatMap(it -> find.matching(it).count());
 	}
 
+	/**
+	 * Define a join.
+	 *
+	 * @param ref reference
+	 * @param target join target
+	 * @return new instance of {@link QuerydslJoinBuilder}.
+	 */
+	<T> QuerydslJoinBuilder<ReactiveSpringDataMongodbQuery<K>, K, T> join(Path<T> ref, Path<T> target) {
+		return new QuerydslJoinBuilder<>(getQueryMixin(), ref, target);
+	}
+
+	/**
+	 * Define a join.
+	 *
+	 * @param ref reference
+	 * @param target join target
+	 * @return new instance of {@link QuerydslJoinBuilder}.
+	 */
+	<T> QuerydslJoinBuilder<ReactiveSpringDataMongodbQuery<K>, K, T> join(CollectionPathBase<?, T, ?> ref,
+			Path<T> target) {
+
+		return new QuerydslJoinBuilder<>(getQueryMixin(), ref, target);
+	}
+
+	/**
+	 * Define a constraint for an embedded object.
+	 *
+	 * @param collection collection must not be {@literal null}.
+	 * @param target target must not be {@literal null}.
+	 * @return new instance of {@link QuerydslAnyEmbeddedBuilder}.
+	 */
+	<T> QuerydslAnyEmbeddedBuilder<ReactiveSpringDataMongodbQuery<K>, K> anyEmbedded(
+			Path<? extends Collection<T>> collection, Path<T> target) {
+
+		return new QuerydslAnyEmbeddedBuilder<>(getQueryMixin(), collection);
+	}
+
 	protected Mono<Query> createQuery() {
 
 		QueryMetadata metadata = getQueryMixin().getMetadata();
 
-		return createQuery(createReactiveFilter(metadata), metadata.getProjection(), metadata.getModifiers(),
+		return createQuery(createFilter(metadata), metadata.getProjection(), metadata.getModifiers(),
 				metadata.getOrderBy());
 	}
 
@@ -128,8 +160,7 @@ class ReactiveSpringDataMongodbQuery<K> extends SpringDataMongodbQuerySupport<Re
 				.defaultIfEmpty(createQuery(null)) //
 				.map(it -> {
 
-					Document fields = createProjection(projection);
-					BasicQuery basicQuery = new BasicQuery(it, fields == null ? new Document() : fields);
+					BasicQuery basicQuery = new BasicQuery(it, createProjection(projection));
 
 					Integer limit = modifiers.getLimitAsInteger();
 					Integer offset = modifiers.getOffsetAsInteger();
@@ -148,11 +179,11 @@ class ReactiveSpringDataMongodbQuery<K> extends SpringDataMongodbQuerySupport<Re
 				});
 	}
 
-	protected Mono<Predicate> createReactiveFilter(QueryMetadata metadata) {
+	protected Mono<Predicate> createFilter(QueryMetadata metadata) {
 
 		if (!metadata.getJoins().isEmpty()) {
 
-			return createReactiveJoinFilter(metadata).map(it -> ExpressionUtils.allOf(metadata.getWhere(), it))
+			return createJoinFilter(metadata).map(it -> ExpressionUtils.allOf(metadata.getWhere(), it))
 					.switchIfEmpty(Mono.justOrEmpty(metadata.getWhere()));
 		}
 
@@ -166,7 +197,7 @@ class ReactiveSpringDataMongodbQuery<K> extends SpringDataMongodbQuerySupport<Re
 	 * @return
 	 */
 	@SuppressWarnings("unchecked")
-	protected Mono<Predicate> createReactiveJoinFilter(QueryMetadata metadata) {
+	protected Mono<Predicate> createJoinFilter(QueryMetadata metadata) {
 
 		MultiValueMap<Expression<?>, Mono<Predicate>> predicates = new LinkedMultiValueMap<>();
 		List<JoinExpression> joins = metadata.getJoins();
@@ -199,7 +230,7 @@ class ReactiveSpringDataMongodbQuery<K> extends SpringDataMongodbQuerySupport<Re
 
 		Path<?> source = (Path) ((Operation) joins.get(0).getTarget()).getArg(0);
 		return allOf(predicates.get(source.getRoot())).onErrorResume(NoMatchException.class,
-				e -> Mono.just(ExpressionUtils.predicate(MongodbOps.NO_MATCH, e.source)));
+				e -> Mono.just(ExpressionUtils.predicate(QuerydslMongoOps.NO_MATCH, e.source)));
 	}
 
 	private Mono<Predicate> allOf(@Nullable Collection<Mono<Predicate>> predicates) {
@@ -215,8 +246,8 @@ class ReactiveSpringDataMongodbQuery<K> extends SpringDataMongodbQuerySupport<Re
 	 */
 	protected Flux<Object> getIds(Class<?> targetType, Mono<Predicate> condition) {
 
-		return condition.flatMapMany(it -> getJoinIds(targetType, it))
-				.switchIfEmpty(Flux.defer(() -> getJoinIds(targetType, (Predicate) null)));
+		return condition.flatMapMany(it -> getIds(targetType, it))
+				.switchIfEmpty(Flux.defer(() -> getIds(targetType, (Predicate) null)));
 	}
 
 	/**
@@ -226,18 +257,12 @@ class ReactiveSpringDataMongodbQuery<K> extends SpringDataMongodbQuerySupport<Re
 	 * @param condition must not be {@literal null}.
 	 * @return empty {@link List} if none found.
 	 */
-	protected Flux<Object> getJoinIds(Class<?> targetType, @Nullable Predicate condition) {
+	protected Flux<Object> getIds(Class<?> targetType, @Nullable Predicate condition) {
 
 		return createQuery(Mono.justOrEmpty(condition), null, QueryModifiers.EMPTY, Collections.emptyList())
 				.flatMapMany(query -> mongoOperations.findDistinct(query, "_id", targetType, Object.class));
 	}
 
-	@Override
-	protected List<Object> getIds(Class<?> aClass, Predicate predicate) {
-		throw new UnsupportedOperationException(
-				"Use create Flux<Object> getIds(Class<?> targetType, Mono<Predicate> condition)");
-	}
-
 	/**
 	 * Marker exception to indicate no matches for a query using reference Id's.
 	 */

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/repository/support/SimpleMongoRepository.java

@@ -36,7 +36,7 @@ import org.springframework.data.mongodb.core.query.Criteria;
 import org.springframework.data.mongodb.core.query.Query;
 import org.springframework.data.mongodb.repository.MongoRepository;
 import org.springframework.data.mongodb.repository.query.MongoEntityInformation;
-import org.springframework.data.support.PageableExecutionUtils;
+import org.springframework.data.repository.support.PageableExecutionUtils;
 import org.springframework.data.util.StreamUtils;
 import org.springframework.data.util.Streamable;
 import org.springframework.lang.Nullable;
@@ -52,7 +52,6 @@ import com.mongodb.client.result.DeleteResult;
  * @author Thomas Darimont
  * @author Mark Paluch
  * @author Mehran Behnam
- * @author Jens Schauder
  */
 public class SimpleMongoRepository<T, ID> implements MongoRepository<T, ID> {
 
@@ -74,10 +73,6 @@ public class SimpleMongoRepository<T, ID> implements MongoRepository<T, ID> {
 		this.mongoOperations = mongoOperations;
 	}
 
-	// -------------------------------------------------------------------------
-	// Methods from CrudRepository
-	// -------------------------------------------------------------------------
-
 	/*
 	 * (non-Javadoc)
 	 * @see org.springframework.data.repository.CrudRepository#save(java.lang.Object)
@@ -141,27 +136,6 @@ public class SimpleMongoRepository<T, ID> implements MongoRepository<T, ID> {
 				entityInformation.getCollectionName());
 	}
 
-	/*
-	 * (non-Javadoc)
-	 * @see org.springframework.data.repository.CrudRepository#findAll()
-	 */
-	@Override
-	public List<T> findAll() {
-		return findAll(new Query());
-	}
-
-	/*
-	 * (non-Javadoc)
-	 * @see org.springframework.data.repository.CrudRepository#findAllById(java.lang.Iterable)
-	 */
-	@Override
-	public Iterable<T> findAllById(Iterable<ID> ids) {
-
-		Assert.notNull(ids, "The given Ids of entities not be null!");
-
-		return findAll(getIdQuery(ids));
-	}
-
 	/*
 	 * (non-Javadoc)
 	 * @see org.springframework.data.repository.CrudRepository#count()
@@ -202,19 +176,6 @@ public class SimpleMongoRepository<T, ID> implements MongoRepository<T, ID> {
 		}
 	}
 
-	/*
-	 * (non-Javadoc)
-	 * @see org.springframework.data.repository.CrudRepository#deleteAllById(java.lang.Iterable)
-	 */
-	@Override
-	public void deleteAllById(Iterable<? extends ID> ids) {
-
-		Assert.notNull(ids, "The given Iterable of ids must not be null!");
-
-		mongoOperations.remove(getIdQuery(ids), entityInformation.getJavaType(),
-				entityInformation.getCollectionName());
-	}
-
 	/*
 	 * (non-Javadoc)
 	 * @see org.springframework.data.repository.CrudRepository#delete(java.lang.Iterable)
@@ -222,7 +183,7 @@ public class SimpleMongoRepository<T, ID> implements MongoRepository<T, ID> {
 	@Override
 	public void deleteAll(Iterable<? extends T> entities) {
 
-		Assert.notNull(entities, "The given Iterable of entities must not be null!");
+		Assert.notNull(entities, "The given Iterable of entities not be null!");
 
 		entities.forEach(this::delete);
 	}
@@ -236,9 +197,27 @@ public class SimpleMongoRepository<T, ID> implements MongoRepository<T, ID> {
 		mongoOperations.remove(new Query(), entityInformation.getCollectionName());
 	}
 
-	// -------------------------------------------------------------------------
-	// Methods from PagingAndSortingRepository
-	// -------------------------------------------------------------------------
+	/*
+	 * (non-Javadoc)
+	 * @see org.springframework.data.repository.CrudRepository#findAll()
+	 */
+	@Override
+	public List<T> findAll() {
+		return findAll(new Query());
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see org.springframework.data.repository.CrudRepository#findAllById(java.lang.Iterable)
+	 */
+	@Override
+	public Iterable<T> findAllById(Iterable<ID> ids) {
+
+		Assert.notNull(ids, "The given Ids of entities not be null!");
+
+		return findAll(new Query(new Criteria(entityInformation.getIdAttribute())
+				.in(toCollection(ids))));
+	}
 
 	/*
 	 * (non-Javadoc)
@@ -267,10 +246,6 @@ public class SimpleMongoRepository<T, ID> implements MongoRepository<T, ID> {
 		return findAll(new Query().with(sort));
 	}
 
-	// -------------------------------------------------------------------------
-	// Methods from MongoRepository
-	// -------------------------------------------------------------------------
-
 	/*
 	 * (non-Javadoc)
 	 * @see org.springframework.data.mongodb.repository.MongoRepository#insert(java.lang.Object)
@@ -301,33 +276,23 @@ public class SimpleMongoRepository<T, ID> implements MongoRepository<T, ID> {
 		return new ArrayList<>(mongoOperations.insertAll(list));
 	}
 
-	// -------------------------------------------------------------------------
-	// Methods from QueryByExampleExecutor
-	// -------------------------------------------------------------------------
-
 	/*
 	 * (non-Javadoc)
-	 * @see org.springframework.data.repository.query.QueryByExampleExecutor#findOne(org.springframework.data.domain.Example)
+	 * @see org.springframework.data.mongodb.repository.MongoRepository#findAllByExample(org.springframework.data.domain.Example, org.springframework.data.domain.Pageable)
 	 */
 	@Override
-	public <S extends T> Optional<S> findOne(Example<S> example) {
+	public <S extends T> Page<S> findAll(final Example<S> example, Pageable pageable) {
 
 		Assert.notNull(example, "Sample must not be null!");
+		Assert.notNull(pageable, "Pageable must not be null!");
 
 		Query query = new Query(new Criteria().alike(example)) //
-				.collation(entityInformation.getCollation());
+				.collation(entityInformation.getCollation()).with(pageable); //
 
-		return Optional
-				.ofNullable(mongoOperations.findOne(query, example.getProbeType(), entityInformation.getCollectionName()));
-	}
+		List<S> list = mongoOperations.find(query, example.getProbeType(), entityInformation.getCollectionName());
 
-	/*
-	 * (non-Javadoc)
-	 * @see org.springframework.data.mongodb.repository.MongoRepository#findAllByExample(org.springframework.data.domain.Example)
-	 */
-	@Override
-	public <S extends T> List<S> findAll(Example<S> example) {
-		return findAll(example, Sort.unsorted());
+		return PageableExecutionUtils.getPage(list, pageable,
+				() -> mongoOperations.count(Query.of(query).limit(-1).skip(-1), example.getProbeType(), entityInformation.getCollectionName()));
 	}
 
 	/*
@@ -349,21 +314,27 @@ public class SimpleMongoRepository<T, ID> implements MongoRepository<T, ID> {
 
 	/*
 	 * (non-Javadoc)
-	 * @see org.springframework.data.mongodb.repository.MongoRepository#findAllByExample(org.springframework.data.domain.Example, org.springframework.data.domain.Pageable)
+	 * @see org.springframework.data.mongodb.repository.MongoRepository#findAllByExample(org.springframework.data.domain.Example)
 	 */
 	@Override
-	public <S extends T> Page<S> findAll(Example<S> example, Pageable pageable) {
+	public <S extends T> List<S> findAll(Example<S> example) {
+		return findAll(example, Sort.unsorted());
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see org.springframework.data.repository.query.QueryByExampleExecutor#findOne(org.springframework.data.domain.Example)
+	 */
+	@Override
+	public <S extends T> Optional<S> findOne(Example<S> example) {
 
 		Assert.notNull(example, "Sample must not be null!");
-		Assert.notNull(pageable, "Pageable must not be null!");
 
 		Query query = new Query(new Criteria().alike(example)) //
-				.collation(entityInformation.getCollation()).with(pageable); //
+				.collation(entityInformation.getCollation());
 
-		List<S> list = mongoOperations.find(query, example.getProbeType(), entityInformation.getCollectionName());
-
-		return PageableExecutionUtils.getPage(list, pageable,
-				() -> mongoOperations.count(Query.of(query).limit(-1).skip(-1), example.getProbeType(), entityInformation.getCollectionName()));
+		return Optional
+				.ofNullable(mongoOperations.findOne(query, example.getProbeType(), entityInformation.getCollectionName()));
 	}
 
 	/*
@@ -396,10 +367,6 @@ public class SimpleMongoRepository<T, ID> implements MongoRepository<T, ID> {
 		return mongoOperations.exists(query, example.getProbeType(), entityInformation.getCollectionName());
 	}
 
-	// -------------------------------------------------------------------------
-	// Utility methods
-	// -------------------------------------------------------------------------
-
 	private Query getIdQuery(Object id) {
 		return new Query(getIdCriteria(id));
 	}
@@ -408,12 +375,6 @@ public class SimpleMongoRepository<T, ID> implements MongoRepository<T, ID> {
 		return where(entityInformation.getIdAttribute()).is(id);
 	}
 
-	private Query getIdQuery(Iterable<? extends ID> ids) {
-
-		return new Query(new Criteria(entityInformation.getIdAttribute())
-				.in(toCollection(ids)));
-	}
-
 	private static <E> Collection<E> toCollection(Iterable<E> ids) {
 		return ids instanceof Collection ? (Collection<E>) ids
 				: StreamUtils.createStreamFromIterator(ids.iterator()).collect(Collectors.toList());
@@ -427,5 +388,4 @@ public class SimpleMongoRepository<T, ID> implements MongoRepository<T, ID> {
 
 		return mongoOperations.find(query, entityInformation.getJavaType(), entityInformation.getCollectionName());
 	}
-
 }

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/repository/support/SimpleReactiveMongoRepository.java

@@ -48,7 +48,6 @@ import com.mongodb.client.result.DeleteResult;
  * @author Oliver Gierke
  * @author Christoph Strobl
  * @author Ruben J Garcia
- * @author Jens Schauder
  * @author Clément Petit
  * @since 2.0
  */
@@ -67,9 +66,232 @@ public class SimpleReactiveMongoRepository<T, ID extends Serializable> implement
 		this.mongoOperations = mongoOperations;
 	}
 
-	// -------------------------------------------------------------------------
-	// Methods from ReactiveCrudRepository
-	// -------------------------------------------------------------------------
+	/*
+	 * (non-Javadoc)
+	 * @see org.springframework.data.repository.reactive.ReactiveCrudRepository#findById(java.lang.Object)
+	 */
+	@Override
+	public Mono<T> findById(ID id) {
+
+		Assert.notNull(id, "The given id must not be null!");
+
+		return mongoOperations.findById(id, entityInformation.getJavaType(), entityInformation.getCollectionName());
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see org.springframework.data.repository.reactive.ReactiveCrudRepository#findById(org.reactivestreams.Publisher)
+	 */
+	@Override
+	public Mono<T> findById(Publisher<ID> publisher) {
+
+		Assert.notNull(publisher, "The given id must not be null!");
+
+		return Mono.from(publisher).flatMap(
+				id -> mongoOperations.findById(id, entityInformation.getJavaType(), entityInformation.getCollectionName()));
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see org.springframework.data.repository.query.ReactiveQueryByExampleExecutor#findOne(org.springframework.data.domain.Example)
+	 */
+	@Override
+	public <S extends T> Mono<S> findOne(Example<S> example) {
+
+		Assert.notNull(example, "Sample must not be null!");
+
+		Query query = new Query(new Criteria().alike(example)) //
+				.collation(entityInformation.getCollation()) //
+				.limit(2);
+
+		return mongoOperations.find(query, example.getProbeType(), entityInformation.getCollectionName()).buffer(2)
+				.map(vals -> {
+
+					if (vals.size() > 1) {
+						throw new IncorrectResultSizeDataAccessException(1);
+					}
+					return vals.iterator().next();
+				}).next();
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see org.springframework.data.repository.reactive.ReactiveCrudRepository#existsById(java.lang.Object)
+	 */
+	@Override
+	public Mono<Boolean> existsById(ID id) {
+
+		Assert.notNull(id, "The given id must not be null!");
+
+		return mongoOperations.exists(getIdQuery(id), entityInformation.getJavaType(),
+				entityInformation.getCollectionName());
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see org.springframework.data.repository.reactive.ReactiveCrudRepository#existsById(org.reactivestreams.Publisher)
+	 */
+	@Override
+	public Mono<Boolean> existsById(Publisher<ID> publisher) {
+
+		Assert.notNull(publisher, "The given id must not be null!");
+
+		return Mono.from(publisher).flatMap(id -> mongoOperations.exists(getIdQuery(id), entityInformation.getJavaType(),
+				entityInformation.getCollectionName()));
+
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see org.springframework.data.repository.query.ReactiveQueryByExampleExecutor#exists(org.springframework.data.domain.Example)
+	 */
+	@Override
+	public <S extends T> Mono<Boolean> exists(Example<S> example) {
+
+		Assert.notNull(example, "Sample must not be null!");
+
+		Query query = new Query(new Criteria().alike(example)) //
+				.collation(entityInformation.getCollation());
+
+		return mongoOperations.exists(query, example.getProbeType(), entityInformation.getCollectionName());
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see org.springframework.data.repository.reactive.ReactiveSortingRepository#findAll()
+	 */
+	@Override
+	public Flux<T> findAll() {
+		return findAll(new Query());
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see org.springframework.data.repository.reactive.ReactiveCrudRepository#findAllById(java.lang.Iterable)
+	 */
+	@Override
+	public Flux<T> findAllById(Iterable<ID> ids) {
+
+		Assert.notNull(ids, "The given Iterable of Id's must not be null!");
+
+		return findAll(new Query(new Criteria(entityInformation.getIdAttribute())
+				.in(toCollection(ids))));
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see org.springframework.data.repository.reactive.ReactiveCrudRepository#findAllById(org.reactivestreams.Publisher)
+	 */
+	@Override
+	public Flux<T> findAllById(Publisher<ID> ids) {
+
+		Assert.notNull(ids, "The given Publisher of Id's must not be null!");
+
+		return Flux.from(ids).buffer().flatMap(this::findAllById);
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see org.springframework.data.repository.reactive.ReactiveSortingRepository#findAll(org.springframework.data.domain.Sort)
+	 */
+	@Override
+	public Flux<T> findAll(Sort sort) {
+
+		Assert.notNull(sort, "Sort must not be null!");
+
+		return findAll(new Query().with(sort));
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see org.springframework.data.mongodb.repository.ReactiveMongoRepository#findAll(org.springframework.data.domain.Example, org.springframework.data.domain.Sort)
+	 */
+	@Override
+	public <S extends T> Flux<S> findAll(Example<S> example, Sort sort) {
+
+		Assert.notNull(example, "Sample must not be null!");
+		Assert.notNull(sort, "Sort must not be null!");
+
+		Query query = new Query(new Criteria().alike(example)) //
+				.collation(entityInformation.getCollation()) //
+				.with(sort);
+
+		return mongoOperations.find(query, example.getProbeType(), entityInformation.getCollectionName());
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see org.springframework.data.mongodb.repository.ReactiveMongoRepository#findAll(org.springframework.data.domain.Example)
+	 */
+	@Override
+	public <S extends T> Flux<S> findAll(Example<S> example) {
+
+		Assert.notNull(example, "Example must not be null!");
+
+		return findAll(example, Sort.unsorted());
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see org.springframework.data.repository.reactive.ReactiveCrudRepository#count()
+	 */
+	@Override
+	public Mono<Long> count() {
+		return mongoOperations.count(new Query(), entityInformation.getCollectionName());
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see org.springframework.data.repository.query.ReactiveQueryByExampleExecutor#count(org.springframework.data.domain.Example)
+	 */
+	@Override
+	public <S extends T> Mono<Long> count(Example<S> example) {
+
+		Assert.notNull(example, "Sample must not be null!");
+
+		Query query = new Query(new Criteria().alike(example)) //
+				.collation(entityInformation.getCollation());
+
+		return mongoOperations.count(query, example.getProbeType(), entityInformation.getCollectionName());
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see org.springframework.data.mongodb.repository.ReactiveMongoRepository#insert(java.lang.Object)
+	 */
+	@Override
+	public <S extends T> Mono<S> insert(S entity) {
+
+		Assert.notNull(entity, "Entity must not be null!");
+
+		return mongoOperations.insert(entity, entityInformation.getCollectionName());
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see org.springframework.data.mongodb.repository.ReactiveMongoRepository#insert(java.lang.Iterable)
+	 */
+	@Override
+	public <S extends T> Flux<S> insert(Iterable<S> entities) {
+
+		Assert.notNull(entities, "The given Iterable of entities must not be null!");
+
+		Collection<S> source = toCollection(entities);
+
+		return source.isEmpty() ? Flux.empty() : mongoOperations.insertAll(source);
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see org.springframework.data.mongodb.repository.ReactiveMongoRepository#insert(org.reactivestreams.Publisher)
+	 */
+	@Override
+	public <S extends T> Flux<S> insert(Publisher<S> entities) {
+
+		Assert.notNull(entities, "The given Publisher of entities must not be null!");
+
+		return Flux.from(entities).flatMap(entity -> mongoOperations.insert(entity, entityInformation.getCollectionName()));
+	}
 
 	/*
 	 * (non-Javadoc)
@@ -117,100 +339,6 @@ public class SimpleReactiveMongoRepository<T, ID extends Serializable> implement
 				mongoOperations.save(entity, entityInformation.getCollectionName()));
 	}
 
-	/*
-	 * (non-Javadoc)
-	 * @see org.springframework.data.repository.reactive.ReactiveCrudRepository#findById(java.lang.Object)
-	 */
-	@Override
-	public Mono<T> findById(ID id) {
-
-		Assert.notNull(id, "The given id must not be null!");
-
-		return mongoOperations.findById(id, entityInformation.getJavaType(), entityInformation.getCollectionName());
-	}
-
-	/*
-	 * (non-Javadoc)
-	 * @see org.springframework.data.repository.reactive.ReactiveCrudRepository#findById(org.reactivestreams.Publisher)
-	 */
-	@Override
-	public Mono<T> findById(Publisher<ID> publisher) {
-
-		Assert.notNull(publisher, "The given id must not be null!");
-
-		return Mono.from(publisher).flatMap(
-				id -> mongoOperations.findById(id, entityInformation.getJavaType(), entityInformation.getCollectionName()));
-	}
-
-	/*
-	 * (non-Javadoc)
-	 * @see org.springframework.data.repository.reactive.ReactiveCrudRepository#existsById(java.lang.Object)
-	 */
-	@Override
-	public Mono<Boolean> existsById(ID id) {
-
-		Assert.notNull(id, "The given id must not be null!");
-
-		return mongoOperations.exists(getIdQuery(id), entityInformation.getJavaType(),
-				entityInformation.getCollectionName());
-	}
-
-	/*
-	 * (non-Javadoc)
-	 * @see org.springframework.data.repository.reactive.ReactiveCrudRepository#existsById(org.reactivestreams.Publisher)
-	 */
-	@Override
-	public Mono<Boolean> existsById(Publisher<ID> publisher) {
-
-		Assert.notNull(publisher, "The given id must not be null!");
-
-		return Mono.from(publisher).flatMap(id -> mongoOperations.exists(getIdQuery(id), entityInformation.getJavaType(),
-				entityInformation.getCollectionName()));
-	}
-
-	/*
-	 * (non-Javadoc)
-	 * @see org.springframework.data.repository.reactive.ReactiveSortingRepository#findAll()
-	 */
-	@Override
-	public Flux<T> findAll() {
-		return findAll(new Query());
-	}
-
-	/*
-	 * (non-Javadoc)
-	 * @see org.springframework.data.repository.reactive.ReactiveCrudRepository#findAllById(java.lang.Iterable)
-	 */
-	@Override
-	public Flux<T> findAllById(Iterable<ID> ids) {
-
-		Assert.notNull(ids, "The given Iterable of Id's must not be null!");
-
-		return findAll(getIdQuery(ids));
-	}
-
-	/*
-	 * (non-Javadoc)
-	 * @see org.springframework.data.repository.reactive.ReactiveCrudRepository#findAllById(org.reactivestreams.Publisher)
-	 */
-	@Override
-	public Flux<T> findAllById(Publisher<ID> ids) {
-
-		Assert.notNull(ids, "The given Publisher of Id's must not be null!");
-
-		return Flux.from(ids).buffer().flatMap(this::findAllById);
-	}
-
-	/*
-	 * (non-Javadoc)
-	 * @see org.springframework.data.repository.reactive.ReactiveCrudRepository#count()
-	 */
-	@Override
-	public Mono<Long> count() {
-		return mongoOperations.count(new Query(), entityInformation.getCollectionName());
-	}
-
-
 	/*
 	 * (non-Javadoc)
 	 * @see org.springframework.data.repository.reactive.ReactiveCrudRepository#deleteById(java.lang.Object)
@@ -266,19 +394,6 @@ public class SimpleReactiveMongoRepository<T, ID extends Serializable> implement
 		return remove.then();
 	}
 
-	/*
-	 * (non-Javadoc)
-	 * @see org.springframework.data.repository.reactive.ReactiveCrudRepository#deleteAllById(java.lang.Iterable)
-	 */
-	@Override
-	public Mono<Void> deleteAllById(Iterable<? extends ID> ids) {
-
-		Assert.notNull(ids, "The given Iterable of Id's must not be null!");
-
-		return mongoOperations
-				.remove(getIdQuery(ids), entityInformation.getJavaType(), entityInformation.getCollectionName()).then();
-	}
-
 	/*
 	 * (non-Javadoc)
 	 * @see org.springframework.data.repository.reactive.ReactiveCrudRepository#deleteAll(java.lang.Iterable)
@@ -288,14 +403,7 @@ public class SimpleReactiveMongoRepository<T, ID extends Serializable> implement
 
 		Assert.notNull(entities, "The given Iterable of entities must not be null!");
 
-		Collection<?> idCollection = StreamUtils.createStreamFromIterator(entities.iterator()).map(entityInformation::getId)
-				.collect(Collectors.toList());
-
-		Criteria idsInCriteria = where(entityInformation.getIdAttribute()).in(idCollection);
-
-		return mongoOperations
-				.remove(new Query(idsInCriteria), entityInformation.getJavaType(), entityInformation.getCollectionName())
-				.then();
+		return Flux.fromIterable(entities).flatMap(this::delete).then();
 	}
 
 	/*
@@ -322,150 +430,6 @@ public class SimpleReactiveMongoRepository<T, ID extends Serializable> implement
 		return mongoOperations.remove(new Query(), entityInformation.getCollectionName()).then(Mono.empty());
 	}
 
-	// -------------------------------------------------------------------------
-	// Methods from ReactiveSortingRepository
-	// -------------------------------------------------------------------------
-
-	/*
-	 * (non-Javadoc)
-	 * @see org.springframework.data.repository.reactive.ReactiveSortingRepository#findAll(org.springframework.data.domain.Sort)
-	 */
-	@Override
-	public Flux<T> findAll(Sort sort) {
-
-		Assert.notNull(sort, "Sort must not be null!");
-
-		return findAll(new Query().with(sort));
-	}
-
-	// -------------------------------------------------------------------------
-	// Methods from ReactiveMongoRepository
-	// -------------------------------------------------------------------------
-
-	/*
-	 * (non-Javadoc)
-	 * @see org.springframework.data.mongodb.repository.ReactiveMongoRepository#insert(java.lang.Object)
-	 */
-	@Override
-	public <S extends T> Mono<S> insert(S entity) {
-
-		Assert.notNull(entity, "Entity must not be null!");
-
-		return mongoOperations.insert(entity, entityInformation.getCollectionName());
-	}
-
-	/*
-	 * (non-Javadoc)
-	 * @see org.springframework.data.mongodb.repository.ReactiveMongoRepository#insert(java.lang.Iterable)
-	 */
-	@Override
-	public <S extends T> Flux<S> insert(Iterable<S> entities) {
-
-		Assert.notNull(entities, "The given Iterable of entities must not be null!");
-
-		Collection<S> source = toCollection(entities);
-
-		return source.isEmpty() ? Flux.empty() : mongoOperations.insertAll(source);
-	}
-
-	/*
-	 * (non-Javadoc)
-	 * @see org.springframework.data.mongodb.repository.ReactiveMongoRepository#insert(org.reactivestreams.Publisher)
-	 */
-	@Override
-	public <S extends T> Flux<S> insert(Publisher<S> entities) {
-
-		Assert.notNull(entities, "The given Publisher of entities must not be null!");
-
-		return Flux.from(entities).flatMap(entity -> mongoOperations.insert(entity, entityInformation.getCollectionName()));
-	}
-
-	// -------------------------------------------------------------------------
-	// Methods from ReactiveMongoRepository
-	// -------------------------------------------------------------------------
-
-	/*
-	 * (non-Javadoc)
-	 * @see org.springframework.data.repository.query.ReactiveQueryByExampleExecutor#findOne(org.springframework.data.domain.Example)
-	 */
-	@Override
-	public <S extends T> Mono<S> findOne(Example<S> example) {
-
-		Assert.notNull(example, "Sample must not be null!");
-
-		Query query = new Query(new Criteria().alike(example)) //
-				.collation(entityInformation.getCollation()) //
-				.limit(2);
-
-		return mongoOperations.find(query, example.getProbeType(), entityInformation.getCollectionName()).buffer(2)
-				.map(vals -> {
-
-					if (vals.size() > 1) {
-						throw new IncorrectResultSizeDataAccessException(1);
-					}
-					return vals.iterator().next();
-				}).next();
-	}
-
-	/*
-	 * (non-Javadoc)
-	 * @see org.springframework.data.mongodb.repository.ReactiveMongoRepository#findAll(org.springframework.data.domain.Example)
-	 */
-	@Override
-	public <S extends T> Flux<S> findAll(Example<S> example) {
-
-		Assert.notNull(example, "Example must not be null!");
-
-		return findAll(example, Sort.unsorted());
-	}
-
-	/*
-	 * (non-Javadoc)
-	 * @see org.springframework.data.mongodb.repository.ReactiveMongoRepository#findAll(org.springframework.data.domain.Example, org.springframework.data.domain.Sort)
-	 */
-	@Override
-	public <S extends T> Flux<S> findAll(Example<S> example, Sort sort) {
-
-		Assert.notNull(example, "Sample must not be null!");
-		Assert.notNull(sort, "Sort must not be null!");
-
-		Query query = new Query(new Criteria().alike(example)) //
-				.collation(entityInformation.getCollation()) //
-				.with(sort);
-
-		return mongoOperations.find(query, example.getProbeType(), entityInformation.getCollectionName());
-	}
-
-	/*
-	 * (non-Javadoc)
-	 * @see org.springframework.data.repository.query.ReactiveQueryByExampleExecutor#count(org.springframework.data.domain.Example)
-	 */
-	@Override
-	public <S extends T> Mono<Long> count(Example<S> example) {
-
-		Assert.notNull(example, "Sample must not be null!");
-
-		Query query = new Query(new Criteria().alike(example)) //
-				.collation(entityInformation.getCollation());
-
-		return mongoOperations.count(query, example.getProbeType(), entityInformation.getCollectionName());
-	}
-
-	/*
-	 * (non-Javadoc)
-	 * @see org.springframework.data.repository.query.ReactiveQueryByExampleExecutor#exists(org.springframework.data.domain.Example)
-	 */
-	@Override
-	public <S extends T> Mono<Boolean> exists(Example<S> example) {
-
-		Assert.notNull(example, "Sample must not be null!");
-
-		Query query = new Query(new Criteria().alike(example)) //
-				.collation(entityInformation.getCollation());
-
-		return mongoOperations.exists(query, example.getProbeType(), entityInformation.getCollectionName());
-	}
-
 	private Query getIdQuery(Object id) {
 		return new Query(getIdCriteria(id));
 	}
@@ -474,10 +438,6 @@ public class SimpleReactiveMongoRepository<T, ID extends Serializable> implement
 		return where(entityInformation.getIdAttribute()).is(id);
 	}
 
-	private Query getIdQuery(Iterable<? extends ID> ids) {
-		return new Query(where(entityInformation.getIdAttribute()).in(toCollection(ids)));
-	}
-
 	private static <E> Collection<E> toCollection(Iterable<E> ids) {
 		return ids instanceof Collection ? (Collection<E>) ids
 				: StreamUtils.createStreamFromIterator(ids.iterator()).collect(Collectors.toList());

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/repository/support/SpringDataMongodbQuery.java

@@ -15,27 +15,7 @@
  */
 package org.springframework.data.mongodb.repository.support;
 
-import java.util.Collections;
-import java.util.List;
-
-import org.bson.Document;
-
-import org.springframework.data.mongodb.core.ExecutableFindOperation;
 import org.springframework.data.mongodb.core.MongoOperations;
-import org.springframework.data.mongodb.core.query.BasicQuery;
-import org.springframework.data.mongodb.core.query.Query;
-import org.springframework.lang.Nullable;
-
-import com.mysema.commons.lang.CloseableIterator;
-import com.mysema.commons.lang.EmptyCloseableIterator;
-import com.querydsl.core.Fetchable;
-import com.querydsl.core.QueryMetadata;
-import com.querydsl.core.QueryModifiers;
-import com.querydsl.core.QueryResults;
-import com.querydsl.core.types.Expression;
-import com.querydsl.core.types.OrderSpecifier;
-import com.querydsl.core.types.Predicate;
-import com.querydsl.mongodb.document.MongodbDocumentSerializer;
 
 /**
  * Spring Data specific simple {@link com.querydsl.core.Fetchable} {@link com.querydsl.core.SimpleQuery Query}
@@ -45,13 +25,7 @@ import com.querydsl.mongodb.document.MongodbDocumentSerializer;
  * @author Mark Paluch
  * @author Christoph Strobl
  */
-public class SpringDataMongodbQuery<T> extends SpringDataMongodbQuerySupport<SpringDataMongodbQuery<T>>
-		implements Fetchable<T> {
-
-	private final Class<T> entityClass;
-	private final String collection;
-	private final MongoOperations mongoOperations;
-	private final ExecutableFindOperation.FindWithProjection<T> find;
+public class SpringDataMongodbQuery<T> extends QuerydslFetchableMongodbQuery<T, SpringDataMongodbQuery<T>> {
 
 	/**
 	 * Creates a new {@link SpringDataMongodbQuery}.
@@ -59,7 +33,7 @@ public class SpringDataMongodbQuery<T> extends SpringDataMongodbQuerySupport<Spr
 	 * @param operations must not be {@literal null}.
 	 * @param type must not be {@literal null}.
 	 */
-	public SpringDataMongodbQuery(MongoOperations operations, Class<? extends T> type) {
+	public SpringDataMongodbQuery(final MongoOperations operations, final Class<? extends T> type) {
 		this(operations, type, operations.getCollectionName(type));
 	}
 
@@ -70,174 +44,9 @@ public class SpringDataMongodbQuery<T> extends SpringDataMongodbQuerySupport<Spr
 	 * @param type must not be {@literal null}.
 	 * @param collectionName must not be {@literal null} or empty.
 	 */
-	public SpringDataMongodbQuery(MongoOperations operations, Class<? extends T> type,
+	public SpringDataMongodbQuery(final MongoOperations operations, final Class<? extends T> type,
 			String collectionName) {
-		this(new SpringDataMongodbSerializer(operations.getConverter()), operations, type, collectionName);
+
+		super(new SpringDataMongodbSerializer(operations.getConverter()), type, collectionName, operations);
 	}
-
-	private SpringDataMongodbQuery(MongodbDocumentSerializer serializer, MongoOperations operations,
-			Class<? extends T> type, String collectionName) {
-
-		super(serializer);
-
-		this.entityClass = (Class<T>) type;
-		this.collection = collectionName;
-		this.mongoOperations = operations;
-		this.find = mongoOperations.query(this.entityClass).inCollection(collection);
-	}
-
-	/*
-	 * (non-Javadoc)
-	 * @see com.querydsl.core.Fetchable#iterable()
-	 */
-	@Override
-	public CloseableIterator<T> iterate() {
-
-		try {
-			org.springframework.data.util.CloseableIterator<? extends T> stream = mongoOperations.stream(createQuery(),
-					entityClass, collection);
-
-			return new CloseableIterator<T>() {
-
-				@Override
-				public boolean hasNext() {
-					return stream.hasNext();
-				}
-
-				@Override
-				public T next() {
-					return stream.next();
-				}
-
-				@Override
-				public void remove() {
-					throw new UnsupportedOperationException("Cannot remove from iterator while streaming data.");
-				}
-
-				@Override
-				public void close() {
-					stream.close();
-				}
-			};
-		} catch (RuntimeException e) {
-			return handleException(e, new EmptyCloseableIterator<>());
-		}
-	}
-
-	/*
-	 * (non-Javadoc)
-	 * @see com.querydsl.core.Fetchable#fetch()
-	 */
-	@Override
-	public List<T> fetch() {
-		try {
-			return find.matching(createQuery()).all();
-		} catch (RuntimeException e) {
-			return handleException(e, Collections.emptyList());
-		}
-	}
-
-	/*
-	 * (non-Javadoc)
-	 * @see com.querydsl.core.Fetchable#fetchFirst()
-	 */
-	@Override
-	public T fetchFirst() {
-		try {
-			return find.matching(createQuery()).firstValue();
-		} catch (RuntimeException e) {
-			return handleException(e, null);
-		}
-	}
-
-	/*
-	 * (non-Javadoc)
-	 * @see com.querydsl.core.Fetchable#fetchOne()
-	 */
-	@Override
-	public T fetchOne() {
-		try {
-			return find.matching(createQuery()).oneValue();
-		} catch (RuntimeException e) {
-			return handleException(e, null);
-		}
-	}
-
-	/*
-	 * (non-Javadoc)
-	 * @see com.querydsl.core.Fetchable#fetchResults()
-	 */
-	@Override
-	public QueryResults<T> fetchResults() {
-
-		long total = fetchCount();
-		return total > 0L ? new QueryResults<>(fetch(), getQueryMixin().getMetadata().getModifiers(), total)
-				: QueryResults.emptyResults();
-	}
-
-	/*
-	 * (non-Javadoc)
-	 * @see com.querydsl.core.Fetchable#fetchCount()
-	 */
-	@Override
-	public long fetchCount() {
-		try {
-			return find.matching(Query.of(createQuery()).skip(-1).limit(-1)).count();
-		} catch (RuntimeException e) {
-			return handleException(e, 0L);
-		}
-	}
-
-	protected org.springframework.data.mongodb.core.query.Query createQuery() {
-
-		QueryMetadata metadata = getQueryMixin().getMetadata();
-
-		return createQuery(createFilter(metadata), metadata.getProjection(), metadata.getModifiers(),
-				metadata.getOrderBy());
-	}
-
-	protected org.springframework.data.mongodb.core.query.Query createQuery(@Nullable Predicate filter,
-			@Nullable Expression<?> projection, QueryModifiers modifiers, List<OrderSpecifier<?>> orderBy) {
-
-		Document fields = createProjection(projection);
-		BasicQuery basicQuery = new BasicQuery(createQuery(filter), fields == null ? new Document() : fields);
-
-		Integer limit = modifiers.getLimitAsInteger();
-		Integer offset = modifiers.getOffsetAsInteger();
-
-		if (limit != null) {
-			basicQuery.limit(limit);
-		}
-		if (offset != null) {
-			basicQuery.skip(offset);
-		}
-		if (orderBy.size() > 0) {
-			basicQuery.setSortObject(createSort(orderBy));
-		}
-
-		return basicQuery;
-	}
-
-	/**
-	 * Fetch the list of ids matching a given condition.
-	 *
-	 * @param targetType must not be {@literal null}.
-	 * @param condition must not be {@literal null}.
-	 * @return empty {@link List} if none found.
-	 */
-	protected List<Object> getIds(Class<?> targetType, Predicate condition) {
-
-		Query query = createQuery(condition, null, QueryModifiers.EMPTY, Collections.emptyList());
-		return mongoOperations.findDistinct(query, "_id", targetType, Object.class);
-	}
-
-	private static <T> T handleException(RuntimeException e, T defaultValue) {
-
-		if (e.getClass().getName().endsWith("$NoResults")) {
-			return defaultValue;
-		}
-
-		throw e;
-	}
-
 }

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/repository/support/SpringDataMongodbQuerySupport.java

@@ -1,142 +0,0 @@
-/*
- * Copyright 2021 the original author or authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      https://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.springframework.data.mongodb.repository.support;
-
-import java.util.List;
-
-import org.bson.Document;
-import org.bson.codecs.DocumentCodec;
-import org.bson.json.JsonMode;
-import org.bson.json.JsonWriterSettings;
-
-import org.springframework.beans.DirectFieldAccessor;
-
-import com.mongodb.MongoClientSettings;
-import com.querydsl.core.support.QueryMixin;
-import com.querydsl.core.types.OrderSpecifier;
-import com.querydsl.mongodb.document.AbstractMongodbQuery;
-import com.querydsl.mongodb.document.MongodbDocumentSerializer;
-
-/**
- * Support query type to augment Spring Data-specific {@link #toString} representations and
- * {@link org.springframework.data.domain.Sort} creation.
- *
- * @author Mark Paluch
- * @since 3.3
- */
-abstract class SpringDataMongodbQuerySupport<Q extends SpringDataMongodbQuerySupport<Q>>
-		extends AbstractMongodbQuery<Q> {
-
-	private final QueryMixin<Q> superQueryMixin;
-
-	private static final JsonWriterSettings JSON_WRITER_SETTINGS = JsonWriterSettings.builder().outputMode(JsonMode.SHELL)
-			.build();
-
-	private final MongodbDocumentSerializer serializer;
-
-	@SuppressWarnings("unchecked")
-	SpringDataMongodbQuerySupport(MongodbDocumentSerializer serializer) {
-		super(serializer);
-		this.serializer = serializer;
-
-		DirectFieldAccessor fieldAccessor = new DirectFieldAccessor(this);
-		this.superQueryMixin = (QueryMixin<Q>) fieldAccessor.getPropertyValue("queryMixin");
-	}
-
-	/**
-	 * Returns the {@literal Mongo Shell} representation of the query. <br />
-	 * The following query
-	 *
-	 * <pre class="code">
-	 *
-	 * where(p.lastname.eq("Matthews")).orderBy(p.firstname.asc()).offset(1).limit(5);
-	 * </pre>
-	 *
-	 * results in
-	 *
-	 * <pre class="code">
-	 *
-	 * find({"lastname" : "Matthews"}).sort({"firstname" : 1}).skip(1).limit(5)
-	 * </pre>
-	 *
-	 * Note that encoding to {@link String} may fail when using data types that cannot be encoded or DBRef's without an
-	 * identifier.
-	 *
-	 * @return never {@literal null}.
-	 */
-	@Override
-	public String toString() {
-
-		Document projection = createProjection(getQueryMixin().getMetadata().getProjection());
-		Document sort = createSort(getQueryMixin().getMetadata().getOrderBy());
-		DocumentCodec codec = new DocumentCodec(MongoClientSettings.getDefaultCodecRegistry());
-
-		StringBuilder sb = new StringBuilder("find(" + asDocument().toJson(JSON_WRITER_SETTINGS, codec));
-		if (projection != null && projection.isEmpty()) {
-			sb.append(", ").append(projection.toJson(JSON_WRITER_SETTINGS, codec));
-		}
-		sb.append(")");
-		if (!sort.isEmpty()) {
-			sb.append(".sort(").append(sort.toJson(JSON_WRITER_SETTINGS, codec)).append(")");
-		}
-		if (getQueryMixin().getMetadata().getModifiers().getOffset() != null) {
-			sb.append(".skip(").append(getQueryMixin().getMetadata().getModifiers().getOffset()).append(")");
-		}
-		if (getQueryMixin().getMetadata().getModifiers().getLimit() != null) {
-			sb.append(".limit(").append(getQueryMixin().getMetadata().getModifiers().getLimit()).append(")");
-		}
-		return sb.toString();
-	}
-
-	/**
-	 * Get the where definition as a Document instance
-	 *
-	 * @return
-	 */
-	public Document asDocument() {
-		return createQuery(getQueryMixin().getMetadata().getWhere());
-	}
-
-	/**
-	 * Obtain the {@literal Mongo Shell} json query representation.
-	 *
-	 * @return never {@literal null}.
-	 */
-	public String toJson() {
-		return toJson(JSON_WRITER_SETTINGS);
-	}
-
-	/**
-	 * Obtain the json query representation applying given {@link JsonWriterSettings settings}.
-	 *
-	 * @param settings must not be {@literal null}.
-	 * @return never {@literal null}.
-	 */
-	public String toJson(JsonWriterSettings settings) {
-		return asDocument().toJson(settings);
-	}
-
-	/**
-	 * Compute the sort {@link Document} from the given list of {@link OrderSpecifier order specifiers}.
-	 *
-	 * @param orderSpecifiers can be {@literal null}.
-	 * @return an empty {@link Document} if predicate is {@literal null}.
-	 * @see MongodbDocumentSerializer#toSort(List)
-	 */
-	protected Document createSort(List<OrderSpecifier<?>> orderSpecifiers) {
-		return serializer.toSort(orderSpecifiers);
-	}
-}

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/repository/support/SpringDataMongodbSerializer.java

@@ -22,7 +22,6 @@ import java.util.Set;
 import java.util.regex.Pattern;
 
 import org.bson.Document;
-
 import org.springframework.data.mapping.context.MappingContext;
 import org.springframework.data.mongodb.core.convert.MongoConverter;
 import org.springframework.data.mongodb.core.convert.QueryMapper;
@@ -40,7 +39,6 @@ import com.querydsl.core.types.Path;
 import com.querydsl.core.types.PathMetadata;
 import com.querydsl.core.types.PathType;
 import com.querydsl.mongodb.MongodbSerializer;
-import com.querydsl.mongodb.document.MongodbDocumentSerializer;
 
 /**
  * Custom {@link MongodbSerializer} to take mapping information into account when building keys for constraints.

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/util/BsonUtils.java

@@ -17,14 +17,12 @@ package org.springframework.data.mongodb.util;
 
 import java.util.Arrays;
 import java.util.Collection;
-import java.util.Collections;
 import java.util.Date;
 import java.util.Map;
 import java.util.StringJoiner;
 import java.util.function.Function;
 import java.util.stream.StreamSupport;
 
-import org.bson.BSONObject;
 import org.bson.BsonBinary;
 import org.bson.BsonBoolean;
 import org.bson.BsonDouble;
@@ -38,11 +36,11 @@ import org.bson.codecs.DocumentCodec;
 import org.bson.conversions.Bson;
 import org.bson.json.JsonParseException;
 import org.bson.types.ObjectId;
+
 import org.springframework.core.convert.converter.Converter;
 import org.springframework.data.mongodb.CodecRegistryProvider;
 import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
-import org.springframework.util.CollectionUtils;
 import org.springframework.util.ObjectUtils;
 import org.springframework.util.StringUtils;
 
@@ -52,8 +50,6 @@ import com.mongodb.DBRef;
 import com.mongodb.MongoClientSettings;
 
 /**
- * Internal API for operations on {@link Bson} elements that can be either {@link Document} or {@link DBObject}.
- *
  * @author Christoph Strobl
  * @author Mark Paluch
  * @since 2.0
@@ -74,9 +70,6 @@ public class BsonUtils {
 		if (bson instanceof BasicDBObject) {
 			return ((BasicDBObject) bson);
 		}
-		if (bson instanceof DBObject) {
-			return ((DBObject) bson).toMap();
-		}
 
 		return (Map) bson.toBsonDocument(Document.class, MongoClientSettings.getDefaultCodecRegistry());
 	}
@@ -84,110 +77,14 @@ public class BsonUtils {
 	public static void addToMap(Bson bson, String key, @Nullable Object value) {
 
 		if (bson instanceof Document) {
-
 			((Document) bson).put(key, value);
 			return;
 		}
-		if (bson instanceof BSONObject) {
-
-			((BSONObject) bson).put(key, value);
+		if (bson instanceof DBObject) {
+			((DBObject) bson).put(key, value);
 			return;
 		}
-
-		throw new IllegalArgumentException(String.format(
-				"Cannot add key/value pair to %s. as map. Given Bson must be a Document or BSONObject!", bson.getClass()));
-	}
-
-	/**
-	 * Add all entries from the given {@literal source} {@link Map} to the {@literal target}.
-	 *
-	 * @param target must not be {@literal null}.
-	 * @param source must not be {@literal null}.
-	 * @since 3.2
-	 */
-	public static void addAllToMap(Bson target, Map<String, ?> source) {
-
-		if (target instanceof Document) {
-
-			((Document) target).putAll(source);
-			return;
-		}
-
-		if (target instanceof BSONObject) {
-
-			((BSONObject) target).putAll(source);
-			return;
-		}
-
-		throw new IllegalArgumentException(
-				String.format("Cannot add all to %s. Given Bson must be a Document or BSONObject.", target.getClass()));
-	}
-
-	/**
-	 * Check if a given entry (key/value pair) is present in the given {@link Bson}.
-	 *
-	 * @param bson must not be {@literal null}.
-	 * @param key must not be {@literal null}.
-	 * @param value can be {@literal null}.
-	 * @return {@literal true} if (key/value pair) is present.
-	 * @since 3.2
-	 */
-	public static boolean contains(Bson bson, String key, @Nullable Object value) {
-
-		if (bson instanceof Document) {
-
-			Document doc = (Document) bson;
-			return doc.containsKey(key) && ObjectUtils.nullSafeEquals(doc.get(key), value);
-		}
-		if (bson instanceof BSONObject) {
-
-			BSONObject bsonObject = (BSONObject) bson;
-			return bsonObject.containsField(key) && ObjectUtils.nullSafeEquals(bsonObject.get(key), value);
-		}
-
-		Map<String, Object> map = asMap(bson);
-		return map.containsKey(key) && ObjectUtils.nullSafeEquals(map.get(key), value);
-	}
-
-	/**
-	 * Remove {@code _id : null} from the given {@link Bson} if present.
-	 *
-	 * @param bson must not be {@literal null}.
-	 * @since 3.2
-	 */
-	public static boolean removeNullId(Bson bson) {
-
-		if (!contains(bson, "_id", null)) {
-			return false;
-		}
-
-		removeFrom(bson, "_id");
-		return true;
-	}
-
-	/**
-	 * Remove the given {@literal key} from the {@link Bson} value.
-	 *
-	 * @param bson must not be {@literal null}.
-	 * @param key must not be {@literal null}.
-	 * @since 3.2
-	 */
-	static void removeFrom(Bson bson, String key) {
-
-		if (bson instanceof Document) {
-
-			((Document) bson).remove(key);
-			return;
-		}
-
-		if (bson instanceof BSONObject) {
-
-			((BSONObject) bson).removeField(key);
-			return;
-		}
-
-		throw new IllegalArgumentException(
-				String.format("Cannot remove from %s. Given Bson must be a Document or BSONObject.", bson.getClass()));
+		throw new IllegalArgumentException("o_O what's that? Cannot add value to " + bson.getClass());
 	}
 
 	/**
@@ -349,13 +246,7 @@ public class BsonUtils {
 	 * @since 3.0
 	 */
 	public static boolean isJsonDocument(@Nullable String value) {
-
-		if(!StringUtils.hasText(value)) {
-			return false;
-		}
-
-		String potentialJson = value.trim();
-		return potentialJson.startsWith("{") && potentialJson.endsWith("}");
+		return StringUtils.hasText(value) && (value.startsWith("{") && value.endsWith("}"));
 	}
 
 	/**
@@ -494,67 +385,6 @@ public class BsonUtils {
 		return null;
 	}
 
-	/**
-	 * Returns the given source object as {@link Bson}, i.e. {@link Document}s and maps as is or throw
-	 * {@link IllegalArgumentException}.
-	 *
-	 * @param source
-	 * @return the converted/casted source object.
-	 * @throws IllegalArgumentException if {@code source} cannot be converted/cast to {@link Bson}.
-	 * @since 3.2.3
-	 * @see #supportsBson(Object)
-	 */
-	@SuppressWarnings("unchecked")
-	public static Bson asBson(Object source) {
-
-		if (source instanceof Document) {
-			return (Document) source;
-		}
-
-		if (source instanceof BasicDBObject) {
-			return (BasicDBObject) source;
-		}
-
-		if (source instanceof DBObject) {
-			return new Document(((DBObject) source).toMap());
-		}
-
-		if (source instanceof Map) {
-			return new Document((Map<String, Object>) source);
-		}
-
-		throw new IllegalArgumentException(String.format("Cannot convert %s to Bson", source));
-	}
-
-	/**
-	 * Returns the given source can be used/converted as {@link Bson}.
-	 *
-	 * @param source
-	 * @return {@literal true} if the given source can be converted to {@link Bson}.
-	 * @since 3.2.3
-	 */
-	public static boolean supportsBson(Object source) {
-		return source instanceof DBObject || source instanceof Map;
-	}
-
-	/**
-	 * Returns given object as {@link Collection}. Will return the {@link Collection} as is if the source is a
-	 * {@link Collection} already, will convert an array into a {@link Collection} or simply create a single element
-	 * collection for everything else.
-	 *
-	 * @param source must not be {@literal null}.
-	 * @return never {@literal null}.
-	 * @since 3.2
-	 */
-	public static Collection<?> asCollection(Object source) {
-
-		if (source instanceof Collection) {
-			return (Collection<?>) source;
-		}
-
-		return source.getClass().isArray() ? CollectionUtils.arrayToList(source) : Collections.singleton(source);
-	}
-
 	@Nullable
 	private static String toJson(@Nullable Object value) {