diff --git a/apache-olingo/Samples.md b/apache-olingo/Samples.md
new file mode 100644
index 0000000000..def8971d64
--- /dev/null
+++ b/apache-olingo/Samples.md
@@ -0,0 +1,21 @@
+##  OData test URLs
+
+This following table contains test URLs that can be used with the Olingo V2 demo project.
+
+| URL                                      | Description                                     |
+|------------------------------------------|-------------------------------------------------|
+| `http://localhost:8180/odata/$metadata`  | fetch OData metadata document |
+| `http://localhost:8180/odata/CarMakers?$top=10&$skip=10` | Get 10 entities starting at offset 10 |
+| `http://localhost:8180/odata/CarMakers?$count` | Return total count of entities in this set |
+| `http://localhost:8180/odata/CarMakers?$filter=startswith(Name,'B')` | Return entities where the *Name* property starts with 'B' |
+| `http://localhost:8180/odata/CarModels?$filter=Year eq 2008 and CarMakerDetails/Name eq 'BWM'` | Return *CarModel* entities where the *Name* property of its maker  starts with 'B' |
+| `http://localhost:8180/odata/CarModels(1L)?$expand=CarMakerDetails` | Return the *CarModel* with primary key '1', along with its maker|
+| `http://localhost:8180/odata/CarModels(1L)?$select=Name,Sku` | Return the *CarModel* with primary key '1', returing only its *Name* and *Sku* properties |
+| `http://localhost:8180/odata/CarModels?$orderBy=Name asc,Sku desc` | Return *CarModel* entities, ordered by the their *Name* and *Sku* properties |
+| `http://localhost:8180/odata/CarModels?$format=json` | Return *CarModel* entities, using a JSON representation|
+
+
+
+
+
+
diff --git a/apache-olingo/olingo2/.gitignore b/apache-olingo/olingo2/.gitignore
new file mode 100644
index 0000000000..153c9335eb
--- /dev/null
+++ b/apache-olingo/olingo2/.gitignore
@@ -0,0 +1,29 @@
+HELP.md
+/target/
+!.mvn/wrapper/maven-wrapper.jar
+
+### STS ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+.sts4-cache
+
+### IntelliJ IDEA ###
+.idea
+*.iws
+*.iml
+*.ipr
+
+### NetBeans ###
+/nbproject/private/
+/nbbuild/
+/dist/
+/nbdist/
+/.nb-gradle/
+/build/
+
+### VS Code ###
+.vscode/
diff --git a/apache-olingo/olingo2/pom.xml b/apache-olingo/olingo2/pom.xml
new file mode 100644
index 0000000000..4fc81e5e49
--- /dev/null
+++ b/apache-olingo/olingo2/pom.xml
@@ -0,0 +1,108 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+	<modelVersion>4.0.0</modelVersion>
+	<parent>
+		<groupId>org.springframework.boot</groupId>
+		<artifactId>spring-boot-starter-parent</artifactId>
+		<version>2.1.3.RELEASE</version>
+		<relativePath /> <!-- lookup parent from repository -->
+	</parent>
+	<groupId>org.baeldung.examples.olingo2</groupId>
+	<artifactId>olingo2-sample</artifactId>
+	<version>0.0.1-SNAPSHOT</version>
+	<name>olingo2-sample</name>
+	<description>Sample Olingo 2 Project</description>
+
+	<properties>
+		<java.version>1.8</java.version>
+		<olingo2.version>2.0.11</olingo2.version>
+	</properties>
+
+	<dependencies>
+
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-jersey</artifactId>
+		</dependency>
+
+
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-data-jpa</artifactId>
+		</dependency>
+
+
+		<dependency>
+			<groupId>com.h2database</groupId>
+			<artifactId>h2</artifactId>
+			<scope>runtime</scope>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-configuration-processor</artifactId>
+			<optional>true</optional>
+		</dependency>
+		<dependency>
+			<groupId>org.projectlombok</groupId>
+			<artifactId>lombok</artifactId>
+			<optional>true</optional>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-test</artifactId>
+			<scope>test</scope>
+		</dependency>
+
+		<!-- Olingo 2 Dependencies -->
+		<dependency>
+			<groupId>org.apache.olingo</groupId>
+			<artifactId>olingo-odata2-core</artifactId>
+			<version>${olingo2.version}</version>
+			<!-- Avoid jax-rs version conflict by excluding Olingo's version -->
+			<exclusions>
+				<exclusion>
+					<groupId>javax.ws.rs</groupId>
+					<artifactId>javax.ws.rs-api</artifactId>
+				</exclusion>
+			</exclusions>
+		</dependency>
+		<dependency>
+			<groupId>org.apache.olingo</groupId>
+			<artifactId>olingo-odata2-api</artifactId>
+			<version>${olingo2.version}</version>
+		</dependency>
+		<dependency>
+			<groupId>org.apache.olingo</groupId>
+			<artifactId>olingo-odata2-jpa-processor-api</artifactId>
+			<version>${olingo2.version}</version>
+		</dependency>
+		<dependency>
+			<groupId>org.apache.olingo</groupId>
+			<artifactId>olingo-odata2-jpa-processor-core</artifactId>
+			<version>${olingo2.version}</version>
+		</dependency>
+		<dependency>
+			<groupId>org.apache.olingo</groupId>
+			<artifactId>olingo-odata2-jpa-processor-ref</artifactId>
+			<version>${olingo2.version}</version>
+			<exclusions>
+				<exclusion>
+					<groupId>org.eclipse.persistence</groupId>
+					<artifactId>eclipselink</artifactId>
+				</exclusion>
+			</exclusions>
+		</dependency>
+	</dependencies>
+
+	<build>
+		<plugins>
+			<plugin>
+				<groupId>org.springframework.boot</groupId>
+				<artifactId>spring-boot-maven-plugin</artifactId>
+			</plugin>
+		</plugins>
+	</build>
+
+</project>
diff --git a/apache-olingo/olingo2/src/main/java/org/baeldung/examples/olingo2/CarsODataJPAServiceFactory.java b/apache-olingo/olingo2/src/main/java/org/baeldung/examples/olingo2/CarsODataJPAServiceFactory.java
new file mode 100644
index 0000000000..65a0428154
--- /dev/null
+++ b/apache-olingo/olingo2/src/main/java/org/baeldung/examples/olingo2/CarsODataJPAServiceFactory.java
@@ -0,0 +1,298 @@
+package org.baeldung.examples.olingo2;
+
+import java.util.List;
+import java.util.Map;
+
+import javax.persistence.EntityGraph;
+import javax.persistence.EntityManager;
+import javax.persistence.EntityManagerFactory;
+import javax.persistence.EntityTransaction;
+import javax.persistence.FlushModeType;
+import javax.persistence.LockModeType;
+import javax.persistence.Persistence;
+import javax.persistence.Query;
+import javax.persistence.StoredProcedureQuery;
+import javax.persistence.SynchronizationType;
+import javax.persistence.TypedQuery;
+import javax.persistence.criteria.CriteriaBuilder;
+import javax.persistence.criteria.CriteriaDelete;
+import javax.persistence.criteria.CriteriaQuery;
+import javax.persistence.criteria.CriteriaUpdate;
+import javax.persistence.metamodel.Metamodel;
+import javax.servlet.http.HttpServletRequest;
+
+import org.apache.olingo.odata2.api.processor.ODataContext;
+import org.apache.olingo.odata2.jpa.processor.api.ODataJPAContext;
+import org.apache.olingo.odata2.jpa.processor.api.ODataJPAServiceFactory;
+import org.apache.olingo.odata2.jpa.processor.api.exception.ODataJPARuntimeException;
+import org.baeldung.examples.olingo2.JerseyConfig.EntityManagerFilter;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.orm.jpa.EntityManagerFactoryUtils;
+import org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean;
+import org.springframework.stereotype.Component;
+
+/**
+ * ODataJPAServiceFactory implementation for our sample domain 
+ * @author Philippe
+ *
+ */
+@Component
+public class CarsODataJPAServiceFactory extends ODataJPAServiceFactory {
+
+    private static final Logger log = LoggerFactory.getLogger(CarsODataJPAServiceFactory.class);
+
+    public CarsODataJPAServiceFactory() {
+        // Enable detailed error messages (useful for debugging)
+        setDetailErrors(true);
+    }
+
+    /**
+     * This method will be called by Olingo on every request to
+     * initialize the ODataJPAContext that will be used. 
+     */
+    @Override
+    public ODataJPAContext initializeODataJPAContext() throws ODataJPARuntimeException {
+
+        log.info("[I32] >>> initializeODataJPAContext()");
+        ODataJPAContext ctx = getODataJPAContext();
+        ODataContext octx = ctx.getODataContext();
+        HttpServletRequest request = (HttpServletRequest)octx.getParameter(ODataContext.HTTP_SERVLET_REQUEST_OBJECT);
+        EntityManager em = (EntityManager)request.getAttribute(EntityManagerFilter.EM_REQUEST_ATTRIBUTE);
+                
+        // Here we're passing the EM that was created by the EntityManagerFilter (see JerseyConfig)
+        ctx.setEntityManager(new EntityManagerWrapper(em));
+        ctx.setPersistenceUnitName("default");
+        
+        // We're managing the EM's lifecycle, so we must inform Olingo that it should not
+        // try to manage transactions and/or persistence sessions
+        ctx.setContainerManaged(true);                
+        return ctx;
+    }
+
+    static class EntityManagerWrapper implements EntityManager {
+
+        private EntityManager delegate;
+
+        public void persist(Object entity) {
+            log.info("[I68] persist: entity.class=" + entity.getClass()
+                .getSimpleName());
+            delegate.persist(entity);
+            // delegate.flush();
+        }
+
+        public <T> T merge(T entity) {
+            log.info("[I74] merge: entity.class=" + entity.getClass()
+                .getSimpleName());
+            return delegate.merge(entity);
+        }
+
+        public void remove(Object entity) {
+            log.info("[I78] remove: entity.class=" + entity.getClass()
+                .getSimpleName());
+            delegate.remove(entity);
+        }
+
+        public <T> T find(Class<T> entityClass, Object primaryKey) {
+            return delegate.find(entityClass, primaryKey);
+        }
+
+        public <T> T find(Class<T> entityClass, Object primaryKey, Map<String, Object> properties) {
+            return delegate.find(entityClass, primaryKey, properties);
+        }
+
+        public <T> T find(Class<T> entityClass, Object primaryKey, LockModeType lockMode) {
+            return delegate.find(entityClass, primaryKey, lockMode);
+        }
+
+        public <T> T find(Class<T> entityClass, Object primaryKey, LockModeType lockMode, Map<String, Object> properties) {
+            return delegate.find(entityClass, primaryKey, lockMode, properties);
+        }
+
+        public <T> T getReference(Class<T> entityClass, Object primaryKey) {
+            return delegate.getReference(entityClass, primaryKey);
+        }
+
+        public void flush() {
+            delegate.flush();
+        }
+
+        public void setFlushMode(FlushModeType flushMode) {
+            delegate.setFlushMode(flushMode);
+        }
+
+        public FlushModeType getFlushMode() {
+            return delegate.getFlushMode();
+        }
+
+        public void lock(Object entity, LockModeType lockMode) {
+            delegate.lock(entity, lockMode);
+        }
+
+        public void lock(Object entity, LockModeType lockMode, Map<String, Object> properties) {
+            delegate.lock(entity, lockMode, properties);
+        }
+
+        public void refresh(Object entity) {
+            delegate.refresh(entity);
+        }
+
+        public void refresh(Object entity, Map<String, Object> properties) {
+            delegate.refresh(entity, properties);
+        }
+
+        public void refresh(Object entity, LockModeType lockMode) {
+            delegate.refresh(entity, lockMode);
+        }
+
+        public void refresh(Object entity, LockModeType lockMode, Map<String, Object> properties) {
+            delegate.refresh(entity, lockMode, properties);
+        }
+
+        public void clear() {
+            delegate.clear();
+        }
+
+        public void detach(Object entity) {
+            delegate.detach(entity);
+        }
+
+        public boolean contains(Object entity) {
+            return delegate.contains(entity);
+        }
+
+        public LockModeType getLockMode(Object entity) {
+            return delegate.getLockMode(entity);
+        }
+
+        public void setProperty(String propertyName, Object value) {
+            delegate.setProperty(propertyName, value);
+        }
+
+        public Map<String, Object> getProperties() {
+            return delegate.getProperties();
+        }
+
+        public Query createQuery(String qlString) {
+            return delegate.createQuery(qlString);
+        }
+
+        public <T> TypedQuery<T> createQuery(CriteriaQuery<T> criteriaQuery) {
+            return delegate.createQuery(criteriaQuery);
+        }
+
+        public Query createQuery(CriteriaUpdate updateQuery) {
+            return delegate.createQuery(updateQuery);
+        }
+
+        public Query createQuery(CriteriaDelete deleteQuery) {
+            return delegate.createQuery(deleteQuery);
+        }
+
+        public <T> TypedQuery<T> createQuery(String qlString, Class<T> resultClass) {
+            return delegate.createQuery(qlString, resultClass);
+        }
+
+        public Query createNamedQuery(String name) {
+            return delegate.createNamedQuery(name);
+        }
+
+        public <T> TypedQuery<T> createNamedQuery(String name, Class<T> resultClass) {
+            return delegate.createNamedQuery(name, resultClass);
+        }
+
+        public Query createNativeQuery(String sqlString) {
+            return delegate.createNativeQuery(sqlString);
+        }
+
+        public Query createNativeQuery(String sqlString, Class resultClass) {
+            return delegate.createNativeQuery(sqlString, resultClass);
+        }
+
+        public Query createNativeQuery(String sqlString, String resultSetMapping) {
+            return delegate.createNativeQuery(sqlString, resultSetMapping);
+        }
+
+        public StoredProcedureQuery createNamedStoredProcedureQuery(String name) {
+            return delegate.createNamedStoredProcedureQuery(name);
+        }
+
+        public StoredProcedureQuery createStoredProcedureQuery(String procedureName) {
+            return delegate.createStoredProcedureQuery(procedureName);
+        }
+
+        public StoredProcedureQuery createStoredProcedureQuery(String procedureName, Class... resultClasses) {
+            return delegate.createStoredProcedureQuery(procedureName, resultClasses);
+        }
+
+        public StoredProcedureQuery createStoredProcedureQuery(String procedureName, String... resultSetMappings) {
+            return delegate.createStoredProcedureQuery(procedureName, resultSetMappings);
+        }
+
+        public void joinTransaction() {
+            delegate.joinTransaction();
+        }
+
+        public boolean isJoinedToTransaction() {
+            return delegate.isJoinedToTransaction();
+        }
+
+        public <T> T unwrap(Class<T> cls) {
+            return delegate.unwrap(cls);
+        }
+
+        public Object getDelegate() {
+            return delegate.getDelegate();
+        }
+
+        public void close() {
+            log.info("[I229] close");
+            delegate.close();
+        }
+
+        public boolean isOpen() {
+            boolean isOpen = delegate.isOpen();
+            log.info("[I236] isOpen: " + isOpen);
+            return isOpen;
+        }
+
+        public EntityTransaction getTransaction() {
+            log.info("[I240] getTransaction()");
+            return delegate.getTransaction();
+        }
+
+        public EntityManagerFactory getEntityManagerFactory() {
+            return delegate.getEntityManagerFactory();
+        }
+
+        public CriteriaBuilder getCriteriaBuilder() {
+            return delegate.getCriteriaBuilder();
+        }
+
+        public Metamodel getMetamodel() {
+            return delegate.getMetamodel();
+        }
+
+        public <T> EntityGraph<T> createEntityGraph(Class<T> rootType) {
+            return delegate.createEntityGraph(rootType);
+        }
+
+        public EntityGraph<?> createEntityGraph(String graphName) {
+            return delegate.createEntityGraph(graphName);
+        }
+
+        public EntityGraph<?> getEntityGraph(String graphName) {
+            return delegate.getEntityGraph(graphName);
+        }
+
+        public <T> List<EntityGraph<? super T>> getEntityGraphs(Class<T> entityClass) {
+            return delegate.getEntityGraphs(entityClass);
+        }
+
+        public EntityManagerWrapper(EntityManager delegate) {
+            this.delegate = delegate;
+        }
+
+    }
+
+}
diff --git a/apache-olingo/olingo2/src/main/java/org/baeldung/examples/olingo2/JerseyConfig.java b/apache-olingo/olingo2/src/main/java/org/baeldung/examples/olingo2/JerseyConfig.java
new file mode 100644
index 0000000000..78caf99861
--- /dev/null
+++ b/apache-olingo/olingo2/src/main/java/org/baeldung/examples/olingo2/JerseyConfig.java
@@ -0,0 +1,125 @@
+    package org.baeldung.examples.olingo2;
+
+import java.io.IOException;
+
+import javax.persistence.EntityManager;
+import javax.persistence.EntityManagerFactory;
+import javax.persistence.EntityTransaction;
+import javax.servlet.ServletContext;
+import javax.servlet.http.HttpServletRequest;
+import javax.ws.rs.ApplicationPath;
+import javax.ws.rs.Path;
+import javax.ws.rs.container.ContainerRequestContext;
+import javax.ws.rs.container.ContainerRequestFilter;
+import javax.ws.rs.container.ContainerResponseContext;
+import javax.ws.rs.container.ContainerResponseFilter;
+import javax.ws.rs.core.Context;
+import javax.ws.rs.ext.Provider;
+
+import org.apache.olingo.odata2.api.ODataServiceFactory;
+import org.apache.olingo.odata2.core.rest.ODataRootLocator;
+import org.apache.olingo.odata2.core.rest.app.ODataApplication;
+import org.glassfish.jersey.server.ResourceConfig;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.stereotype.Component;
+
+/**
+ * Jersey JAX-RS configuration
+ * @author Philippe
+ *
+ */
+@Component
+@ApplicationPath("/odata")
+public class JerseyConfig extends ResourceConfig {
+    
+    
+    public JerseyConfig(CarsODataJPAServiceFactory serviceFactory, EntityManagerFactory emf) {        
+        
+        ODataApplication app = new ODataApplication();
+        
+        app
+          .getClasses()
+          .forEach( c -> {
+              // Avoid using the default RootLocator, as we want
+              // a Spring Managed one
+              if ( !ODataRootLocator.class.isAssignableFrom(c)) {
+                  register(c);
+              }
+          });
+        
+        register(new CarsRootLocator(serviceFactory)); 
+        register( new EntityManagerFilter(emf));
+    }
+    
+    /**
+     * This filter handles the EntityManager transaction lifecycle.
+     * @author Philippe
+     *
+     */
+    @Provider
+    public static class EntityManagerFilter implements ContainerRequestFilter, ContainerResponseFilter {
+
+        private static final Logger log = LoggerFactory.getLogger(EntityManagerFilter.class);
+        public static final String EM_REQUEST_ATTRIBUTE = EntityManagerFilter.class.getName() + "_ENTITY_MANAGER";
+
+        private final EntityManagerFactory emf;
+
+        @Context
+        private HttpServletRequest httpRequest;
+
+        public EntityManagerFilter(EntityManagerFactory emf) {
+            this.emf = emf;
+        }
+
+        @Override
+        public void filter(ContainerRequestContext ctx) throws IOException {
+            log.info("[I60] >>> filter");
+            EntityManager em = this.emf.createEntityManager();
+            httpRequest.setAttribute(EM_REQUEST_ATTRIBUTE, em);
+
+            // Start a new transaction unless we have a simple GET
+            if (!"GET".equalsIgnoreCase(ctx.getMethod())) {
+                em.getTransaction()
+                    .begin();
+            }
+        }
+
+        @Override
+        public void filter(ContainerRequestContext requestContext, ContainerResponseContext responseContext) throws IOException {
+
+            log.info("[I68] <<< filter");
+            EntityManager em = (EntityManager) httpRequest.getAttribute(EM_REQUEST_ATTRIBUTE);
+
+            if (!"GET".equalsIgnoreCase(requestContext.getMethod())) {
+                EntityTransaction t = em.getTransaction();
+                if (t.isActive()) {
+                    if (!t.getRollbackOnly()) {
+                        t.commit();
+                    }
+                }
+            }
+
+            em.close();
+
+        }
+
+    }
+
+    @Path("/")
+    public static class CarsRootLocator extends ODataRootLocator {
+
+        private CarsODataJPAServiceFactory serviceFactory;
+
+        public CarsRootLocator(CarsODataJPAServiceFactory serviceFactory) {
+            this.serviceFactory = serviceFactory;
+        }
+
+        @Override
+        public ODataServiceFactory getServiceFactory() {
+            return this.serviceFactory;
+        }
+
+    }
+
+}
diff --git a/apache-olingo/olingo2/src/main/java/org/baeldung/examples/olingo2/Olingo2SampleApplication.java b/apache-olingo/olingo2/src/main/java/org/baeldung/examples/olingo2/Olingo2SampleApplication.java
new file mode 100644
index 0000000000..fa58612088
--- /dev/null
+++ b/apache-olingo/olingo2/src/main/java/org/baeldung/examples/olingo2/Olingo2SampleApplication.java
@@ -0,0 +1,14 @@
+package org.baeldung.examples.olingo2;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.boot.builder.SpringApplicationBuilder;
+import org.springframework.boot.web.servlet.support.SpringBootServletInitializer;
+
+@SpringBootApplication
+public class Olingo2SampleApplication extends SpringBootServletInitializer {
+
+    public static void main(String[] args) {        
+        SpringApplication.run(Olingo2SampleApplication.class);
+    }
+}
diff --git a/apache-olingo/olingo2/src/main/java/org/baeldung/examples/olingo2/domain/CarMaker.java b/apache-olingo/olingo2/src/main/java/org/baeldung/examples/olingo2/domain/CarMaker.java
new file mode 100644
index 0000000000..42a3eaa59d
--- /dev/null
+++ b/apache-olingo/olingo2/src/main/java/org/baeldung/examples/olingo2/domain/CarMaker.java
@@ -0,0 +1,36 @@
+package org.baeldung.examples.olingo2.domain;
+
+import java.util.List;
+
+import javax.persistence.CascadeType;
+import javax.persistence.Column;
+import javax.persistence.Entity;
+import javax.persistence.GeneratedValue;
+import javax.persistence.GenerationType;
+import javax.persistence.Id;
+import javax.persistence.OneToMany;
+import javax.persistence.Table;
+import javax.validation.constraints.NotNull;
+
+import lombok.Data;
+
+@Entity
+@Data
+@Table(name="car_maker")
+public class CarMaker {
+    
+    @Id
+    @GeneratedValue(strategy=GenerationType.IDENTITY)    
+    private Long id;
+    
+    @NotNull
+    @Column(name="name")
+    private String name;
+    
+    @OneToMany(mappedBy="maker",
+      orphanRemoval = true,
+      cascade=CascadeType.ALL)
+    private List<CarModel> models;
+    
+
+}
diff --git a/apache-olingo/olingo2/src/main/java/org/baeldung/examples/olingo2/domain/CarModel.java b/apache-olingo/olingo2/src/main/java/org/baeldung/examples/olingo2/domain/CarModel.java
new file mode 100644
index 0000000000..a4f2a04f6e
--- /dev/null
+++ b/apache-olingo/olingo2/src/main/java/org/baeldung/examples/olingo2/domain/CarModel.java
@@ -0,0 +1,38 @@
+package org.baeldung.examples.olingo2.domain;
+
+
+import javax.persistence.Entity;
+import javax.persistence.FetchType;
+import javax.persistence.GeneratedValue;
+import javax.persistence.GenerationType;
+import javax.persistence.Id;
+import javax.persistence.JoinColumn;
+import javax.persistence.ManyToOne;
+import javax.persistence.Table;
+import javax.validation.constraints.NotNull;
+
+import lombok.Data;
+
+@Entity
+@Data
+@Table(name="car_model")
+public class CarModel {
+
+    @Id
+    @GeneratedValue(strategy=GenerationType.AUTO)
+    private Long id;
+    
+    @NotNull
+    private String name;
+    
+    @NotNull
+    private Integer year;
+    
+    @NotNull
+    private String sku;
+    
+    @ManyToOne(optional=false, fetch= FetchType.LAZY)
+    @JoinColumn(name="maker_fk")
+    private CarMaker maker;
+
+}
diff --git a/apache-olingo/olingo2/src/main/resources/application.yml b/apache-olingo/olingo2/src/main/resources/application.yml
new file mode 100644
index 0000000000..21563a94fe
--- /dev/null
+++ b/apache-olingo/olingo2/src/main/resources/application.yml
@@ -0,0 +1,12 @@
+server:
+  port: 8180
+  
+spring:
+  jersey:
+    application-path: /odata
+    
+  jpa:
+    show-sql: true
+    open-in-view: false
+    hibernate:
+      ddl-auto: update
\ No newline at end of file
diff --git a/apache-olingo/olingo2/src/main/resources/data.sql b/apache-olingo/olingo2/src/main/resources/data.sql
new file mode 100644
index 0000000000..327f2688c5
--- /dev/null
+++ b/apache-olingo/olingo2/src/main/resources/data.sql
@@ -0,0 +1,12 @@
+insert into car_maker(id,name) values (1,'Special Motors');
+insert into car_maker(id,name) values (2,'BWM');
+insert into car_maker(id,name) values (3,'Dolores');
+
+insert into car_model(id,maker_fk,name,sku,year) values(1,1,'Muze','SM001',2018);
+insert into car_model(id,maker_fk,name,sku,year) values(2,1,'Empada','SM002',2008);
+
+insert into car_model(id,maker_fk,name,sku,year) values(4,2,'BWM-100','BWM100',2008);
+insert into car_model(id,maker_fk,name,sku,year) values(5,2,'BWM-200','BWM200',2009);
+insert into car_model(id,maker_fk,name,sku,year) values(6,2,'BWM-300','BWM300',2008);
+
+alter sequence hibernate_sequence restart with 100;
\ No newline at end of file
diff --git a/apache-olingo/olingo2/src/test/java/org/baeldung/examples/olingo2/Olingo2SampleApplicationTests.java b/apache-olingo/olingo2/src/test/java/org/baeldung/examples/olingo2/Olingo2SampleApplicationTests.java
new file mode 100644
index 0000000000..687f6ab1ff
--- /dev/null
+++ b/apache-olingo/olingo2/src/test/java/org/baeldung/examples/olingo2/Olingo2SampleApplicationTests.java
@@ -0,0 +1,16 @@
+package org.baeldung.examples.olingo2;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.test.context.junit4.SpringRunner;
+
+@RunWith(SpringRunner.class)
+@SpringBootTest
+public class Olingo2SampleApplicationTests {
+
+	@Test
+	public void contextLoads() {
+	}
+
+}
diff --git a/apache-olingo/olingo2/src/test/resources/olingo2-queries.json b/apache-olingo/olingo2/src/test/resources/olingo2-queries.json
new file mode 100644
index 0000000000..9fdade6d10
--- /dev/null
+++ b/apache-olingo/olingo2/src/test/resources/olingo2-queries.json
@@ -0,0 +1,256 @@
+{
+	"info": {
+		"_postman_id": "afa8e1e5-ab0e-4f1d-8b99-b7d1f091f975",
+		"name": "OLingo2 - Cars",
+		"schema": "https://schema.getpostman.com/json/collection/v2.0.0/collection.json"
+	},
+	"item": [
+		{
+			"name": "GET Metadata",
+			"request": {
+				"method": "GET",
+				"header": [],
+				"body": {
+					"mode": "raw",
+					"raw": ""
+				},
+				"url": "http://localhost:8080/odata/$metadata"
+			},
+			"response": []
+		},
+		{
+			"name": "GET All CarMakers",
+			"request": {
+				"method": "GET",
+				"header": [],
+				"body": {
+					"mode": "raw",
+					"raw": ""
+				},
+				"url": "http://localhost:8080/odata/CarMakers"
+			},
+			"response": []
+		},
+		{
+			"name": "GET Makers with Pagination",
+			"request": {
+				"method": "GET",
+				"header": [],
+				"body": {
+					"mode": "raw",
+					"raw": ""
+				},
+				"url": {
+					"raw": "http://localhost:8080/odata/CarMakers?$top=1&$orderby=Name&$skip=3",
+					"protocol": "http",
+					"host": [
+						"localhost"
+					],
+					"port": "8080",
+					"path": [
+						"odata",
+						"CarMakers"
+					],
+					"query": [
+						{
+							"key": "$top",
+							"value": "1"
+						},
+						{
+							"key": "$orderby",
+							"value": "Name"
+						},
+						{
+							"key": "$skip",
+							"value": "3"
+						}
+					]
+				}
+			},
+			"response": []
+		},
+		{
+			"name": "GET Makers and Models",
+			"request": {
+				"method": "GET",
+				"header": [],
+				"body": {
+					"mode": "raw",
+					"raw": ""
+				},
+				"url": {
+					"raw": "http://localhost:8080/odata/CarMakers?$expand=CarModelDetails",
+					"protocol": "http",
+					"host": [
+						"localhost"
+					],
+					"port": "8080",
+					"path": [
+						"odata",
+						"CarMakers"
+					],
+					"query": [
+						{
+							"key": "$expand",
+							"value": "CarModelDetails"
+						}
+					]
+				}
+			},
+			"response": []
+		},
+		{
+			"name": "GET Makers with filter",
+			"request": {
+				"method": "GET",
+				"header": [
+					{
+						"key": "Accept",
+						"value": "application/json",
+						"type": "text"
+					}
+				],
+				"body": {
+					"mode": "raw",
+					"raw": ""
+				},
+				"url": {
+					"raw": "http://localhost:8080/odata/CarMakers?$filter=Name eq 'BWM'&$expand=CarModelDetails",
+					"protocol": "http",
+					"host": [
+						"localhost"
+					],
+					"port": "8080",
+					"path": [
+						"odata",
+						"CarMakers"
+					],
+					"query": [
+						{
+							"key": "$filter",
+							"value": "Name eq 'BWM'"
+						},
+						{
+							"key": "$expand",
+							"value": "CarModelDetails"
+						}
+					]
+				}
+			},
+			"response": []
+		},
+		{
+			"name": "Create CarMaker",
+			"request": {
+				"method": "POST",
+				"header": [
+					{
+						"key": "Content-Type",
+						"name": "Content-Type",
+						"value": "application/atom+xml",
+						"type": "text"
+					},
+					{
+						"key": "Accept",
+						"value": "application/atom+xml",
+						"type": "text"
+					}
+				],
+				"body": {
+					"mode": "raw",
+					"raw": "<?xml version=\"1.0\" encoding=\"utf-8\" ?> \r\n<entry xmlns:d=\"http://schemas.microsoft.com/ado/2007/08/dataservices\"\r\n    xmlns:m=\"http://schemas.microsoft.com/ado/2007/08/dataservices/metadata\" \r\n    xmlns=\"http://www.w3.org/2005/Atom\">\r\n  <title type=\"text\"></title> \r\n  <updated>2019-04-02T21:36:47Z</updated>\r\n  <author> \r\n    <name /> \r\n  </author> \r\n  <category term=\"default.CarMaker\"\r\n      scheme=\"http://schemas.microsoft.com/ado/2007/08/dataservices/scheme\" /> \r\n  <content type=\"application/xml\"> \r\n    <m:properties>\r\n      <d:Name>Lucien</d:Name>\r\n    </m:properties> \r\n  </content> \r\n</entry>"
+				},
+				"url": "http://localhost:8080/odata/CarMakers"
+			},
+			"response": []
+		},
+		{
+			"name": "Create CarModel",
+			"request": {
+				"method": "POST",
+				"header": [
+					{
+						"key": "Content-Type",
+						"name": "Content-Type",
+						"type": "text",
+						"value": "application/atom+xml"
+					},
+					{
+						"key": "Accept",
+						"type": "text",
+						"value": "application/atom+xml"
+					}
+				],
+				"body": {
+					"mode": "raw",
+					"raw": "<?xml version=\"1.0\" encoding=\"utf-8\" ?> \r\n<entry xmlns:d=\"http://schemas.microsoft.com/ado/2007/08/dataservices\"\r\n    xmlns:m=\"http://schemas.microsoft.com/ado/2007/08/dataservices/metadata\" \r\n    xmlns=\"http://www.w3.org/2005/Atom\">\r\n  <title type=\"text\"></title> \r\n  <updated>2019-04-02T21:36:47Z</updated>\r\n  <author> \r\n    <name /> \r\n  </author> \r\n  <link href=\"CarModels(1L)/CarMakerDetails\" \r\n    rel=\"http://schemas.microsoft.com/ado/2007/08/dataservices/related/CarMakerDetails\" \r\n    title=\"CarMakerDetails\" \r\n    type=\"application/atom+xml;type=entry\"></link>  \r\n  <category term=\"default.CarModel\"\r\n      scheme=\"http://schemas.microsoft.com/ado/2007/08/dataservices/scheme\" /> \r\n  <content type=\"application/xml\"> \r\n    <m:properties>\r\n\t    <d:Name>Tata</d:Name>\r\n\t    <d:Sku>TT101</d:Sku>\r\n\t    <d:Year>2018</d:Year>\r\n    </m:properties> \r\n  </content> \r\n</entry>"
+				},
+				"url": "http://localhost:8080/odata/CarModels"
+			},
+			"response": []
+		},
+		{
+			"name": "Update CarMaker",
+			"request": {
+				"method": "PUT",
+				"header": [
+					{
+						"key": "Content-Type",
+						"name": "Content-Type",
+						"type": "text",
+						"value": "application/atom+xml"
+					},
+					{
+						"key": "Accept",
+						"type": "text",
+						"value": "application/atom+xml"
+					}
+				],
+				"body": {
+					"mode": "raw",
+					"raw": "<?xml version=\"1.0\" encoding=\"utf-8\" ?> \r\n<entry xmlns:d=\"http://schemas.microsoft.com/ado/2007/08/dataservices\"\r\n    xmlns:m=\"http://schemas.microsoft.com/ado/2007/08/dataservices/metadata\" \r\n    xmlns=\"http://www.w3.org/2005/Atom\">\r\n  <title type=\"text\"></title> \r\n  <updated>2019-04-02T21:36:47Z</updated>\r\n  <author> \r\n    <name /> \r\n  </author> \r\n  <category term=\"default.CarMaker\"\r\n      scheme=\"http://schemas.microsoft.com/ado/2007/08/dataservices/scheme\" /> \r\n  <content type=\"application/xml\"> \r\n    <m:properties>\r\n      <d:Id>5</d:Id>\r\n      <d:Name>KaiserWagen</d:Name>\r\n    </m:properties> \r\n  </content> \r\n</entry>"
+				},
+				"url": "http://localhost:8080/odata/CarMakers(5L)"
+			},
+			"response": []
+		},
+		{
+			"name": "All CarModels",
+			"request": {
+				"method": "GET",
+				"header": [],
+				"body": {
+					"mode": "raw",
+					"raw": ""
+				},
+				"url": "http://localhost:8080/odata/CarModels"
+			},
+			"response": []
+		},
+		{
+			"name": "Delete CarModel",
+			"request": {
+				"method": "DELETE",
+				"header": [
+					{
+						"key": "Content-Type",
+						"name": "Content-Type",
+						"type": "text",
+						"value": "application/atom+xml"
+					},
+					{
+						"key": "Accept",
+						"type": "text",
+						"value": "application/atom+xml"
+					}
+				],
+				"body": {
+					"mode": "raw",
+					"raw": ""
+				},
+				"url": "http://localhost:8080/odata/CarModels(100L)"
+			},
+			"response": []
+		}
+	]
+}
\ No newline at end of file
diff --git a/apache-olingo/olingo4/.gitignore b/apache-olingo/olingo4/.gitignore
new file mode 100644
index 0000000000..153c9335eb
--- /dev/null
+++ b/apache-olingo/olingo4/.gitignore
@@ -0,0 +1,29 @@
+HELP.md
+/target/
+!.mvn/wrapper/maven-wrapper.jar
+
+### STS ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+.sts4-cache
+
+### IntelliJ IDEA ###
+.idea
+*.iws
+*.iml
+*.ipr
+
+### NetBeans ###
+/nbproject/private/
+/nbbuild/
+/dist/
+/nbdist/
+/.nb-gradle/
+/build/
+
+### VS Code ###
+.vscode/
diff --git a/apache-olingo/olingo4/pom.xml b/apache-olingo/olingo4/pom.xml
new file mode 100644
index 0000000000..794aee0711
--- /dev/null
+++ b/apache-olingo/olingo4/pom.xml
@@ -0,0 +1,95 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+	<modelVersion>4.0.0</modelVersion>
+	<parent>
+		<groupId>org.springframework.boot</groupId>
+		<artifactId>spring-boot-starter-parent</artifactId>
+		<version>2.1.3.RELEASE</version>
+		<relativePath /> <!-- lookup parent from repository -->
+	</parent>
+	<groupId>org.baeldung.examples.olingo4</groupId>
+	<artifactId>olingo4-sample</artifactId>
+	<version>0.0.1-SNAPSHOT</version>
+	<name>olingo4-sample</name>
+	<description>Sample Olingo 4 Project</description>
+
+	<properties>
+		<java.version>1.8</java.version>
+		<odata.version>4.5.0</odata.version>
+	</properties>
+
+	<dependencies>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-data-jpa</artifactId>
+		</dependency>
+
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-configuration-processor</artifactId>
+			<optional>true</optional>
+		</dependency>
+
+		<dependency>
+			<groupId>com.h2database</groupId>
+			<artifactId>h2</artifactId>
+			<scope>runtime</scope>
+		</dependency>
+
+		<dependency>
+			<groupId>org.projectlombok</groupId>
+			<artifactId>lombok</artifactId>
+			<optional>true</optional>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-test</artifactId>
+			<scope>test</scope>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-web</artifactId>
+		</dependency>
+		
+		<dependency>
+			<groupId>org.apache.olingo</groupId>
+			<artifactId>odata-server-api</artifactId>
+			<version>${odata.version}</version>
+		</dependency>
+		<dependency>
+			<groupId>org.apache.olingo</groupId>
+			<artifactId>odata-server-core</artifactId>
+			<version>${odata.version}</version>
+			<scope>runtime</scope>
+		</dependency>
+
+		<dependency>
+			<groupId>org.apache.olingo</groupId>
+			<artifactId>odata-commons-api</artifactId>
+			<version>${odata.version}</version>
+		</dependency>
+		<dependency>
+			<groupId>org.apache.olingo</groupId>
+			<artifactId>odata-commons-core</artifactId>
+			<version>${odata.version}</version>
+		</dependency>
+		
+		<dependency>
+			<groupId>commons-beanutils</groupId>
+			<artifactId>commons-beanutils</artifactId>
+			<version>1.9.3</version>
+		</dependency>
+	</dependencies>
+
+	<build>
+		<plugins>
+			<plugin>
+				<groupId>org.springframework.boot</groupId>
+				<artifactId>spring-boot-maven-plugin</artifactId>
+			</plugin>
+		</plugins>
+	</build>
+
+</project>
diff --git a/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/DefaultODataFactory.java b/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/DefaultODataFactory.java
new file mode 100644
index 0000000000..18f7f8ba24
--- /dev/null
+++ b/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/DefaultODataFactory.java
@@ -0,0 +1,20 @@
+package org.baeldung.examples.olingo4;
+
+import org.apache.olingo.server.api.OData;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
+import org.springframework.stereotype.Component;
+
+/**
+ * Default implementation for ODataFactory 
+ * @author Philippe
+ *
+ */
+@Component
+public class DefaultODataFactory implements ODataFactory {
+
+    @Override
+    public OData newInstance() {
+        return OData.newInstance();
+    }
+
+}
diff --git a/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/ODataFactory.java b/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/ODataFactory.java
new file mode 100644
index 0000000000..9acb4b8c5e
--- /dev/null
+++ b/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/ODataFactory.java
@@ -0,0 +1,8 @@
+package org.baeldung.examples.olingo4;
+
+import org.apache.olingo.server.api.OData;
+
+public interface ODataFactory {
+
+    public OData newInstance();
+}
diff --git a/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/ODataHttpHandlerFactory.java b/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/ODataHttpHandlerFactory.java
new file mode 100644
index 0000000000..27d0737c24
--- /dev/null
+++ b/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/ODataHttpHandlerFactory.java
@@ -0,0 +1,8 @@
+package org.baeldung.examples.olingo4;
+
+import org.apache.olingo.server.api.ODataHttpHandler;
+
+public interface ODataHttpHandlerFactory {
+
+    ODataHttpHandler newInstance();
+}
diff --git a/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/ODataHttpHandlerFactoryImpl.java b/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/ODataHttpHandlerFactoryImpl.java
new file mode 100644
index 0000000000..68d39dc052
--- /dev/null
+++ b/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/ODataHttpHandlerFactoryImpl.java
@@ -0,0 +1,42 @@
+package org.baeldung.examples.olingo4;
+
+import java.util.Collections;
+import java.util.List;
+
+import org.apache.olingo.commons.api.edm.provider.CsdlEdmProvider;
+import org.apache.olingo.server.api.OData;
+import org.apache.olingo.server.api.ODataHttpHandler;
+import org.apache.olingo.server.api.ServiceMetadata;
+import org.apache.olingo.server.api.processor.Processor;
+
+import lombok.Builder;
+
+@Builder
+public class ODataHttpHandlerFactoryImpl implements ODataHttpHandlerFactory {
+    
+    
+    private final ODataFactory odataFactory;
+    private final CsdlEdmProvider edmProvider;
+    private final List<Processor> processors;
+
+    public ODataHttpHandlerFactoryImpl(ODataFactory odataFactory,CsdlEdmProvider edmProvider, List<Processor> processors) {
+        this.odataFactory = odataFactory;
+        this.edmProvider = edmProvider;
+        this.processors = processors;
+    }
+
+    @Override
+    public ODataHttpHandler newInstance() {
+        
+        OData odata = odataFactory.newInstance();
+        ServiceMetadata metadata = odata.createServiceMetadata(edmProvider, Collections.emptyList());
+        ODataHttpHandler handler = odata.createHandler(metadata);
+        
+        // Register all available processors
+        processors.forEach(p -> handler.register(p));
+        
+        
+        return handler;
+    }
+
+}
diff --git a/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/ODataServiceConfiguration.java b/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/ODataServiceConfiguration.java
new file mode 100644
index 0000000000..0cde665359
--- /dev/null
+++ b/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/ODataServiceConfiguration.java
@@ -0,0 +1,35 @@
+package org.baeldung.examples.olingo4;
+
+import java.util.List;
+
+import javax.persistence.EntityManagerFactory;
+import javax.servlet.http.HttpServlet;
+
+import org.apache.olingo.commons.api.edm.provider.CsdlEdmProvider;
+import org.apache.olingo.server.api.processor.Processor;
+import org.baeldung.examples.olingo4.ODataHttpHandlerFactoryImpl.ODataHttpHandlerFactoryImplBuilder;
+import org.springframework.boot.web.servlet.ServletRegistrationBean;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+
+@Configuration
+public class ODataServiceConfiguration {
+
+    @Bean
+    public ServletRegistrationBean<HttpServlet> odataServletRegistration(ODataHttpHandlerFactory factory) {
+        ServletRegistrationBean<HttpServlet> srb = 
+          new ServletRegistrationBean<>(new ODataServlet(factory), "/odata/*");
+        srb.setLoadOnStartup(1);
+        return srb;
+    }
+
+    @Bean
+    public ODataHttpHandlerFactory httpHandlerFactory(CsdlEdmProvider edmProvider, ODataFactory odataFactory, List<Processor> processors) {
+        return new ODataHttpHandlerFactoryImplBuilder()
+          .edmProvider(edmProvider)
+          .odataFactory(odataFactory)
+          .processors(processors)
+          .build();
+    }
+
+}
diff --git a/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/ODataServlet.java b/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/ODataServlet.java
new file mode 100644
index 0000000000..c379124541
--- /dev/null
+++ b/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/ODataServlet.java
@@ -0,0 +1,38 @@
+/**
+ * 
+ */
+package org.baeldung.examples.olingo4;
+
+import java.io.IOException;
+
+import javax.persistence.EntityManager;
+import javax.persistence.EntityManagerFactory;
+import javax.persistence.EntityTransaction;
+import javax.servlet.ServletException;
+import javax.servlet.http.HttpServlet;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+
+import org.apache.olingo.server.api.ODataHttpHandler;
+
+/**
+ * @author Philippe
+ *
+ */
+public class ODataServlet extends HttpServlet {
+
+    private static final long serialVersionUID = 1L;
+    private final ODataHttpHandlerFactory odataHttpHandlerFactory;
+    
+    
+    public ODataServlet(ODataHttpHandlerFactory factory) {
+        this.odataHttpHandlerFactory = factory;
+    }
+
+    @Override
+    protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
+
+        ODataHttpHandler handler = odataHttpHandlerFactory.newInstance();
+        handler.process(req, resp);
+    }
+}
diff --git a/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/Olingo4SampleApplication.java b/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/Olingo4SampleApplication.java
new file mode 100644
index 0000000000..1ac872ea0f
--- /dev/null
+++ b/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/Olingo4SampleApplication.java
@@ -0,0 +1,13 @@
+package org.baeldung.examples.olingo4;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+public class Olingo4SampleApplication {
+
+    public static void main(String[] args) {
+        SpringApplication.run(Olingo4SampleApplication.class, args);
+    }
+
+}
diff --git a/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/domain/CarMaker.java b/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/domain/CarMaker.java
new file mode 100644
index 0000000000..79825b4556
--- /dev/null
+++ b/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/domain/CarMaker.java
@@ -0,0 +1,36 @@
+package org.baeldung.examples.olingo4.domain;
+
+import java.util.List;
+
+import javax.persistence.CascadeType;
+import javax.persistence.Column;
+import javax.persistence.Entity;
+import javax.persistence.GeneratedValue;
+import javax.persistence.GenerationType;
+import javax.persistence.Id;
+import javax.persistence.OneToMany;
+import javax.persistence.Table;
+import javax.validation.constraints.NotNull;
+
+import lombok.Data;
+
+@Entity
+@Data
+@Table(name="car_maker")
+public class CarMaker {
+    
+    @Id
+    @GeneratedValue(strategy=GenerationType.IDENTITY)    
+    private Long id;
+    
+    @NotNull
+    @Column(name="name")
+    private String name;
+    
+    @OneToMany(mappedBy="maker",
+      orphanRemoval = true,
+      cascade=CascadeType.ALL)
+    private List<CarModel> models;
+    
+
+}
diff --git a/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/domain/CarModel.java b/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/domain/CarModel.java
new file mode 100644
index 0000000000..a9254e48b9
--- /dev/null
+++ b/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/domain/CarModel.java
@@ -0,0 +1,38 @@
+package org.baeldung.examples.olingo4.domain;
+
+
+import javax.persistence.Entity;
+import javax.persistence.FetchType;
+import javax.persistence.GeneratedValue;
+import javax.persistence.GenerationType;
+import javax.persistence.Id;
+import javax.persistence.JoinColumn;
+import javax.persistence.ManyToOne;
+import javax.persistence.Table;
+import javax.validation.constraints.NotNull;
+
+import lombok.Data;
+
+@Entity
+@Data
+@Table(name="car_model")
+public class CarModel {
+
+    @Id
+    @GeneratedValue(strategy=GenerationType.AUTO)
+    private Long id;
+    
+    @NotNull
+    private String name;
+    
+    @NotNull
+    private Integer year;
+    
+    @NotNull
+    private String sku;
+    
+    @ManyToOne(optional=false, fetch= FetchType.EAGER   )
+    @JoinColumn(name="maker_fk")
+    private CarMaker maker;
+
+}
diff --git a/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/edm/EdmTypeMapper.java b/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/edm/EdmTypeMapper.java
new file mode 100644
index 0000000000..95797752a2
--- /dev/null
+++ b/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/edm/EdmTypeMapper.java
@@ -0,0 +1,46 @@
+package org.baeldung.examples.olingo4.edm;
+
+import java.util.Collections;
+import java.util.Date;
+import java.util.Map;
+import java.util.UUID;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
+import java.sql.Time;
+import java.util.AbstractMap.SimpleEntry;
+
+import org.apache.olingo.commons.api.edm.EdmPrimitiveTypeKind;
+import org.springframework.stereotype.Component;
+
+@Component
+public class EdmTypeMapper {
+
+    public EdmPrimitiveTypeKind java2edm(Class<?> clazz) {
+        EdmPrimitiveTypeKind result = java2edm.get(clazz);
+        if ( result == null ) {
+            throw new IllegalArgumentException("[E19] Unsupported class mapping: class=" + clazz);
+        }
+        else {
+            return result;
+        }
+    }
+    
+    // Static map used generate attribute metadada based on Java types
+    static Map<Class<?>,EdmPrimitiveTypeKind> java2edm = Collections
+      .unmodifiableMap(Stream.of(
+        new SimpleEntry<>(Boolean.class,EdmPrimitiveTypeKind.Boolean),
+        new SimpleEntry<>(Byte.class,EdmPrimitiveTypeKind.SByte),
+        new SimpleEntry<>(Date.class,EdmPrimitiveTypeKind.Date),
+        new SimpleEntry<>(Time.class,EdmPrimitiveTypeKind.TimeOfDay),
+        new SimpleEntry<>(Number.class,EdmPrimitiveTypeKind.Decimal),
+        new SimpleEntry<>(Float.class,EdmPrimitiveTypeKind.Single),
+        new SimpleEntry<>(Double.class,EdmPrimitiveTypeKind.Double),
+        new SimpleEntry<>(UUID.class,EdmPrimitiveTypeKind.Guid),
+        new SimpleEntry<>(Short.class,EdmPrimitiveTypeKind.Int16),
+        new SimpleEntry<>(Integer.class,EdmPrimitiveTypeKind.Int32),
+        new SimpleEntry<>(Long.class,EdmPrimitiveTypeKind.Int64),
+        new SimpleEntry<>(String.class,EdmPrimitiveTypeKind.String)
+      
+      ).collect(Collectors.toMap((e)-> e.getKey(),(e)-> e.getValue())));
+
+}
diff --git a/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/edm/JpaEdmProvider.java b/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/edm/JpaEdmProvider.java
new file mode 100644
index 0000000000..4cd979e931
--- /dev/null
+++ b/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/edm/JpaEdmProvider.java
@@ -0,0 +1,269 @@
+package org.baeldung.examples.olingo4.edm;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.stream.Collectors;
+
+import javax.persistence.EntityManagerFactory;
+import javax.persistence.metamodel.Attribute.PersistentAttributeType;
+import javax.persistence.metamodel.EntityType;
+import javax.persistence.metamodel.Metamodel;
+import javax.persistence.metamodel.PluralAttribute;
+import javax.persistence.metamodel.SingularAttribute;
+
+import org.apache.olingo.commons.api.edm.FullQualifiedName;
+import org.apache.olingo.commons.api.edm.provider.CsdlAbstractEdmProvider;
+import org.apache.olingo.commons.api.edm.provider.CsdlEntityContainer;
+import org.apache.olingo.commons.api.edm.provider.CsdlEntityContainerInfo;
+import org.apache.olingo.commons.api.edm.provider.CsdlEntitySet;
+import org.apache.olingo.commons.api.edm.provider.CsdlEntityType;
+import org.apache.olingo.commons.api.edm.provider.CsdlNavigationProperty;
+import org.apache.olingo.commons.api.edm.provider.CsdlProperty;
+import org.apache.olingo.commons.api.edm.provider.CsdlPropertyRef;
+import org.apache.olingo.commons.api.edm.provider.CsdlSchema;
+import org.apache.olingo.commons.api.ex.ODataException;
+import org.springframework.stereotype.Component;
+
+@Component
+public class JpaEdmProvider extends CsdlAbstractEdmProvider {
+
+    EntityManagerFactory emf;
+
+    //
+    private EdmTypeMapper typeMapper;
+
+    // Service Namespace
+    public static final String NAMESPACE = "Baeldung.OData";
+
+    // EDM Container
+    public static final String CONTAINER_NAME = "Cars";
+    public static final FullQualifiedName CONTAINER = new FullQualifiedName(NAMESPACE, CONTAINER_NAME);
+    
+    // Caches of OData types by it fully qualified name
+    private Map<FullQualifiedName, CsdlEntityType> cdslName2Type = new HashMap<>();
+
+    public JpaEdmProvider(EntityManagerFactory emf, EdmTypeMapper mapper) {
+        this.emf = emf;
+        this.typeMapper = mapper;
+    }
+
+    /* (non-Javadoc)
+     * @see org.apache.olingo.commons.api.edm.provider.CsdlAbstractEdmProvider#getEntitySet(org.apache.olingo.commons.api.edm.FullQualifiedName, java.lang.String)
+     */
+    @Override
+    public CsdlEntitySet getEntitySet(FullQualifiedName entityContainer, String entitySetName) throws ODataException {
+
+        if (entityContainer.equals(CONTAINER)) {
+
+            EntityType<?> e = emf.getMetamodel()
+                .getEntities()
+                .stream()
+                .filter((ent) -> (ent.getName() + "s")
+                    .equals(entitySetName))
+                .findFirst()
+                .orElse(null);
+
+            if (e != null) {
+                CsdlEntitySet entitySet = new CsdlEntitySet();
+                entitySet
+                  .setName(entitySetName)
+                  .setType(new FullQualifiedName(NAMESPACE, e.getName()));
+                return entitySet;
+            }
+        }
+
+        return null;
+    }
+
+    /* (non-Javadoc)
+     * @see org.apache.olingo.commons.api.edm.provider.CsdlAbstractEdmProvider#getEntityContainerInfo(org.apache.olingo.commons.api.edm.FullQualifiedName)
+     */
+    @Override
+    public CsdlEntityContainerInfo getEntityContainerInfo(FullQualifiedName entityContainerName) throws ODataException {
+
+        // This method is invoked when displaying the Service Document at e.g. http://localhost:8080/DemoService/DemoService.svc
+        if (entityContainerName == null || entityContainerName.equals(CONTAINER)) {
+            CsdlEntityContainerInfo entityContainerInfo = new CsdlEntityContainerInfo();
+            entityContainerInfo.setContainerName(CONTAINER);
+            return entityContainerInfo;
+        }
+
+        return null;
+    }
+
+    /* (non-Javadoc)
+     * @see org.apache.olingo.commons.api.edm.provider.CsdlAbstractEdmProvider#getSchemas()
+     */
+    @Override
+    public List<CsdlSchema> getSchemas() throws ODataException {
+        // create Schema
+        CsdlSchema schema = new CsdlSchema();
+        schema.setNamespace(NAMESPACE);
+
+        // add EntityTypes
+        List<CsdlEntityType> entityTypes = emf.getMetamodel()
+            .getEntities()
+            .stream()
+            .map((e) -> {
+                try {
+                    return getEntityType(new FullQualifiedName(NAMESPACE, e.getName()));
+                } catch (ODataException oe) {
+                    throw new RuntimeException(oe);
+                }
+            })
+            .collect(Collectors.toList());
+
+        schema.setEntityTypes(entityTypes);
+
+        // add EntityContainer
+        schema.setEntityContainer(getEntityContainer());
+
+        // finally
+        List<CsdlSchema> schemas = new ArrayList<CsdlSchema>();
+        schemas.add(schema);
+
+        return schemas;
+    }
+
+    /* (non-Javadoc)
+     * @see org.apache.olingo.commons.api.edm.provider.CsdlAbstractEdmProvider#getEntityContainer()
+     */
+    @Override
+    public CsdlEntityContainer getEntityContainer() throws ODataException {
+        
+        
+        // add EntityTypes
+        List<CsdlEntitySet> entitySets = emf.getMetamodel()
+            .getEntities()
+            .stream()
+            .map((e) -> {
+                try {
+                    // Here we use a simple mapping strategy to map entity types to entity set names:
+                    return getEntitySet(CONTAINER, e.getName() + "s");
+                } catch (ODataException oe) {
+                    throw new RuntimeException(oe);
+                }
+            })
+            .collect(Collectors.toList());
+        
+        // create EntityContainer
+        CsdlEntityContainer entityContainer = new CsdlEntityContainer();
+        entityContainer.setName(CONTAINER_NAME);
+        entityContainer.setEntitySets(entitySets);
+
+        return entityContainer;
+    }
+
+    @Override
+    public CsdlEntityType getEntityType(FullQualifiedName entityTypeName) throws ODataException {
+        
+        CsdlEntityType result = cdslName2Type.get(entityTypeName);
+        if ( result != null ) {
+            return result;
+        }
+
+        Metamodel mm = emf.getMetamodel();
+        result = mm.getEntities()
+            .stream()
+            .filter(et -> entityTypeName.equals(new FullQualifiedName(NAMESPACE, et.getName())))
+            .map(et -> buildODataType(et))
+            .findFirst()
+            .orElse(null);
+
+        // save for future use
+        cdslName2Type.put(entityTypeName, result);
+        return result;
+        
+    }
+
+    /**
+     * Maps a JPA type to its OData counterpart.
+     * @param et
+     * @return
+     */
+    protected CsdlEntityType buildODataType(EntityType<?> et) {
+
+        CsdlEntityType result = new CsdlEntityType();
+        result.setName(et.getName());
+
+        // Process simple properties
+        List<CsdlProperty> properties = et.getDeclaredSingularAttributes()
+            .stream()
+            .filter(attr -> attr.getPersistentAttributeType() == PersistentAttributeType.BASIC)
+            .map(attr -> buildBasicAttribute(et, attr))
+            .collect(Collectors.toList());
+
+        result.setProperties(properties);
+
+        // Process Ids
+        List<CsdlPropertyRef> ids = et.getDeclaredSingularAttributes()
+            .stream()
+            .filter(attr -> attr.getPersistentAttributeType() == PersistentAttributeType.BASIC && attr.isId())
+            .map(attr -> buildRefAttribute(et, attr))
+            .collect(Collectors.toList());
+
+        result.setKey(ids);
+
+        // Process 1:N navs
+        List<CsdlNavigationProperty> navs = et.getDeclaredPluralAttributes()
+            .stream()
+            .map(attr -> buildNavAttribute(et, attr))
+            .collect(Collectors.toList());
+        result.setNavigationProperties(navs);
+        
+        // Process N:1 navs
+        List<CsdlNavigationProperty> navs2 = et.getDeclaredSingularAttributes()
+            .stream()
+            .filter(attr -> attr.getPersistentAttributeType() == PersistentAttributeType.MANY_TO_ONE)
+            .map(attr -> buildNavAttribute(et, attr))
+            .collect(Collectors.toList());
+
+        result.getNavigationProperties().addAll(navs2);
+        
+
+        return result;
+    }
+
+    private CsdlProperty buildBasicAttribute(EntityType<?> et, SingularAttribute<?, ?> attr) {
+
+        CsdlProperty p = new CsdlProperty().setName(attr.getName())
+            .setType(typeMapper.java2edm(attr.getJavaType())
+                .getFullQualifiedName())
+            .setNullable(et.getDeclaredSingularAttribute(attr.getName())
+                .isOptional());
+
+        return p;
+    }
+
+    private CsdlPropertyRef buildRefAttribute(EntityType<?> et, SingularAttribute<?, ?> attr) {
+
+        CsdlPropertyRef p = new CsdlPropertyRef().setName(attr.getName());
+
+        return p;
+    }
+
+    // Build NavProperty for 1:N or M:N associations
+    private CsdlNavigationProperty buildNavAttribute(EntityType<?> et, PluralAttribute<?, ?, ?> attr) {
+
+        CsdlNavigationProperty p = new CsdlNavigationProperty().setName(attr.getName())
+            .setType(new FullQualifiedName(NAMESPACE, attr.getBindableJavaType().getSimpleName()))
+            .setCollection(true)
+            .setNullable(false); 
+
+        return p;
+    }
+
+    // Build NavProperty for N:1 associations
+    private CsdlNavigationProperty buildNavAttribute(EntityType<?> et, SingularAttribute<?, ?> attr) {
+
+        CsdlNavigationProperty p = new CsdlNavigationProperty().setName(attr.getName())
+            .setType(new FullQualifiedName(NAMESPACE, attr.getBindableJavaType().getSimpleName()))
+            .setCollection(false)
+            .setNullable(attr.isOptional());
+
+        return p;
+    }
+    
+}
diff --git a/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/processor/JpaEntityCollectionProcessor.java b/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/processor/JpaEntityCollectionProcessor.java
new file mode 100644
index 0000000000..4a4e5026f3
--- /dev/null
+++ b/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/processor/JpaEntityCollectionProcessor.java
@@ -0,0 +1,161 @@
+package org.baeldung.examples.olingo4.processor;
+
+import java.io.ByteArrayInputStream;
+import java.io.InputStream;
+import java.lang.reflect.InvocationTargetException;
+import java.net.URI;
+import java.net.URISyntaxException;
+import java.util.Collection;
+import java.util.List;
+
+import javax.persistence.EntityManagerFactory;
+import javax.persistence.metamodel.EntityType;
+import javax.persistence.metamodel.SingularAttribute;
+
+import org.apache.commons.beanutils.PropertyUtils;
+import org.apache.olingo.commons.api.data.ContextURL;
+import org.apache.olingo.commons.api.data.Entity;
+import org.apache.olingo.commons.api.data.EntityCollection;
+import org.apache.olingo.commons.api.data.Property;
+import org.apache.olingo.commons.api.data.ValueType;
+import org.apache.olingo.commons.api.edm.EdmEntitySet;
+import org.apache.olingo.commons.api.edm.EdmEntityType;
+import org.apache.olingo.commons.api.edm.EdmNavigationProperty;
+import org.apache.olingo.commons.api.ex.ODataRuntimeException;
+import org.apache.olingo.commons.api.format.ContentType;
+import org.apache.olingo.commons.api.http.HttpHeader;
+import org.apache.olingo.commons.api.http.HttpStatusCode;
+import org.apache.olingo.server.api.OData;
+import org.apache.olingo.server.api.ODataApplicationException;
+import org.apache.olingo.server.api.ODataLibraryException;
+import org.apache.olingo.server.api.ODataRequest;
+import org.apache.olingo.server.api.ODataResponse;
+import org.apache.olingo.server.api.ServiceMetadata;
+import org.apache.olingo.server.api.processor.CountEntityCollectionProcessor;
+import org.apache.olingo.server.api.processor.EntityCollectionProcessor;
+import org.apache.olingo.server.api.serializer.EntityCollectionSerializerOptions;
+import org.apache.olingo.server.api.serializer.ODataSerializer;
+import org.apache.olingo.server.api.serializer.SerializerResult;
+import org.apache.olingo.server.api.uri.UriInfo;
+import org.apache.olingo.server.api.uri.UriParameter;
+import org.apache.olingo.server.api.uri.UriResource;
+import org.apache.olingo.server.api.uri.UriResourceEntitySet;
+import org.baeldung.examples.olingo4.repository.RepositoryRegistry;
+import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.stereotype.Component;
+
+@Component
+public class JpaEntityCollectionProcessor implements CountEntityCollectionProcessor {
+
+    private OData odata;
+    private ServiceMetadata serviceMetadata;
+    private EntityManagerFactory emf;
+    private RepositoryRegistry repositoryRegistry;
+    private JpaEntityMapper entityMapper;
+
+    public JpaEntityCollectionProcessor(EntityManagerFactory emf, RepositoryRegistry repositoryRegistry, JpaEntityMapper entityMapper) {
+        this.emf = emf;
+        this.repositoryRegistry = repositoryRegistry;
+        this.entityMapper = entityMapper;
+    }
+
+    @Override
+    public void init(OData odata, ServiceMetadata serviceMetadata) {
+        this.odata = odata;
+        this.serviceMetadata = serviceMetadata;
+    }
+
+    @Override
+    public void readEntityCollection(ODataRequest request, ODataResponse response, UriInfo uriInfo, ContentType responseFormat) throws ODataApplicationException, ODataLibraryException {
+
+        // 1st we have retrieve the requested EntitySet from the uriInfo object (representation of the parsed service URI)
+        List<UriResource> resourcePaths = uriInfo.getUriResourceParts();
+        UriResourceEntitySet uriResourceEntitySet = (UriResourceEntitySet) resourcePaths.get(0); // in our example, the first segment is the EntitySet
+        EdmEntitySet edmEntitySet = uriResourceEntitySet.getEntitySet();
+
+        // 2nd: fetch the data from backend for this requested EntitySetName
+        // it has to be delivered as EntitySet object
+        EntityCollection entitySet = getData(edmEntitySet, uriInfo);
+
+        // 3rd: create a serializer based on the requested format (json)
+        ODataSerializer serializer = odata.createSerializer(responseFormat);
+
+        // 4th: Now serialize the content: transform from the EntitySet object to InputStream
+        EdmEntityType edmEntityType = edmEntitySet.getEntityType();
+        ContextURL contextUrl = ContextURL.with()
+            .entitySet(edmEntitySet)
+            .build();
+
+        final String id = request.getRawBaseUri() + "/" + edmEntitySet.getName();
+        EntityCollectionSerializerOptions opts = EntityCollectionSerializerOptions.with()
+            .id(id)
+            .contextURL(contextUrl)
+            .build();
+        SerializerResult serializerResult = serializer.entityCollection(serviceMetadata, edmEntityType, entitySet, opts);
+        InputStream serializedContent = serializerResult.getContent();
+
+        // Finally: configure the response object: set the body, headers and status code
+        response.setContent(serializedContent);
+        response.setStatusCode(HttpStatusCode.OK.getStatusCode());
+        response.setHeader(HttpHeader.CONTENT_TYPE, responseFormat.toContentTypeString());
+
+    }
+
+    @Override
+    public void countEntityCollection(ODataRequest request, ODataResponse response, UriInfo uriInfo) throws ODataApplicationException, ODataLibraryException {
+
+        // 1st we have retrieve the requested EntitySet from the uriInfo object (representation of the parsed service URI)
+        List<UriResource> resourcePaths = uriInfo.getUriResourceParts();
+        UriResourceEntitySet uriResourceEntitySet = (UriResourceEntitySet) resourcePaths.get(0); // in our example, the first segment is the EntitySet
+        EdmEntitySet edmEntitySet = uriResourceEntitySet.getEntitySet();
+
+        // 2nd: fetch the data from backend for this requested EntitySetName
+        Long count = getCount(edmEntitySet, uriInfo);
+
+        // Finally: configure the response object: set the body, headers and status code
+        response.setContent(new ByteArrayInputStream(count.toString().getBytes()));
+        response.setStatusCode(HttpStatusCode.OK.getStatusCode());
+        response.setHeader(HttpHeader.CONTENT_TYPE, "text/plain");
+
+    }
+
+    /**
+     * Helper method to retrieve all entities of an entity set from an the backend database
+     * @param edmEntitySet
+     * @param uriInfo
+     * @return
+     */
+    protected EntityCollection getData(EdmEntitySet edmEntitySet, UriInfo uriInfo) {
+
+        EdmEntityType type = edmEntitySet.getEntityType();
+        JpaRepository<?, ?> repo = (JpaRepository<?, ?>)repositoryRegistry.getRepositoryForEntity(type);
+        EntityCollection result = new EntityCollection();
+
+        repo.findAll()
+          .stream()
+          .forEach((it) -> result.getEntities()
+          .add(entityMapper.map2entity(edmEntitySet, it)));
+
+        return result;
+    }
+
+
+    /**
+     * Helper method to get the total size of an entity set
+     * @param edmEntitySet
+     * @param uriInfo
+     * @return
+     */
+    protected Long getCount(EdmEntitySet edmEntitySet, UriInfo uriInfo) {
+        
+        EdmEntityType type = edmEntitySet.getEntityType();
+        JpaRepository<?, ?> repo = (JpaRepository<?, ?>)repositoryRegistry.getRepositoryForEntity(type);
+        EntityCollection result = new EntityCollection();
+
+        return repo.count();
+    }
+    
+    
+
+
+}
diff --git a/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/processor/JpaEntityMapper.java b/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/processor/JpaEntityMapper.java
new file mode 100644
index 0000000000..1978aa4fd6
--- /dev/null
+++ b/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/processor/JpaEntityMapper.java
@@ -0,0 +1,93 @@
+/**
+ * 
+ */
+package org.baeldung.examples.olingo4.processor;
+
+import java.lang.reflect.InvocationTargetException;
+import java.net.URI;
+import java.net.URISyntaxException;
+
+import javax.persistence.EntityManagerFactory;
+import javax.persistence.metamodel.EntityType;
+
+import org.apache.commons.beanutils.PropertyUtils;
+import org.apache.olingo.commons.api.data.Entity;
+import org.apache.olingo.commons.api.data.Property;
+import org.apache.olingo.commons.api.data.ValueType;
+import org.apache.olingo.commons.api.edm.EdmEntitySet;
+import org.apache.olingo.commons.api.ex.ODataRuntimeException;
+import org.springframework.stereotype.Component;
+
+/**
+ * <p>Helper class that converts a JPA entity into an OData entity using
+ * available metadata from the JPA's EntityManagerFactory.</p>
+ * 
+ * @author Philippe
+ *
+ */
+@Component
+public class JpaEntityMapper {
+    
+    private EntityManagerFactory emf;
+
+    public JpaEntityMapper(EntityManagerFactory emf) {
+        this.emf = emf;
+    }
+    
+    
+    public Entity map2entity(EdmEntitySet edmEntitySet, Object entry) {
+
+        EntityType<?> et = emf.getMetamodel()
+            .entity(entry.getClass());
+
+
+        Entity e = new Entity();
+        try {
+            et.getDeclaredSingularAttributes().stream()
+              .forEach( (attr) -> {
+                 if ( !attr.isAssociation()) {
+                     Object v = getPropertyValue(entry,attr.getName());
+                     Property p = new Property(null, attr.getName(),ValueType.PRIMITIVE,v);
+                     e.addProperty(p);
+
+                     if ( attr.isId()) {
+                         e.setId(createId(edmEntitySet.getName(),v));                     
+                     }                     
+                 }                 
+              });
+        } catch (Exception ex) {
+            throw new ODataRuntimeException("[E141] Unable to create OData entity", ex);
+        }
+
+        return e;
+    }
+    
+    
+    public Object getPropertyValue(Object entry, String name) {
+        try {
+            return PropertyUtils.getProperty(entry,name);
+        } catch (IllegalAccessException | InvocationTargetException | NoSuchMethodException e) {
+            throw new ODataRuntimeException("[E141] Unable to read property from entity, property=" + name, e);
+        }
+    }
+    
+    public void setPropertyValue(Object entry, String name,Object value) {
+        try {
+            PropertyUtils.setProperty(entry,name,value);
+        } catch (IllegalAccessException | InvocationTargetException | NoSuchMethodException e) {
+            throw new ODataRuntimeException("[E141] Unable to read property from entity, property=" + name, e);
+        }
+    }
+    
+
+    private URI createId(String entitySetName, Object id)  {
+        try {
+            return new URI(entitySetName + "(" + String.valueOf(id) + ")");
+        } catch (URISyntaxException e) {
+            throw new ODataRuntimeException("[E177] Unable to create URI", e);
+        }
+    }
+    
+
+
+}
diff --git a/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/processor/JpaEntityProcessor.java b/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/processor/JpaEntityProcessor.java
new file mode 100644
index 0000000000..719e5de160
--- /dev/null
+++ b/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/processor/JpaEntityProcessor.java
@@ -0,0 +1,304 @@
+/**
+ * 
+ */
+package org.baeldung.examples.olingo4.processor;
+
+import java.io.InputStream;
+import java.util.List;
+import java.util.Locale;
+import java.util.Optional;
+
+import javax.persistence.EntityManager;
+import javax.persistence.EntityManagerFactory;
+import javax.persistence.metamodel.SingularAttribute;
+
+import org.apache.olingo.commons.api.data.ContextURL;
+import org.apache.olingo.commons.api.data.Entity;
+import org.apache.olingo.commons.api.edm.EdmEntitySet;
+import org.apache.olingo.commons.api.edm.EdmEntityType;
+import org.apache.olingo.commons.api.edm.EdmNavigationProperty;
+import org.apache.olingo.commons.api.ex.ODataRuntimeException;
+import org.apache.olingo.commons.api.format.ContentType;
+import org.apache.olingo.commons.api.http.HttpHeader;
+import org.apache.olingo.commons.api.http.HttpStatusCode;
+import org.apache.olingo.server.api.OData;
+import org.apache.olingo.server.api.ODataApplicationException;
+import org.apache.olingo.server.api.ODataLibraryException;
+import org.apache.olingo.server.api.ODataRequest;
+import org.apache.olingo.server.api.ODataResponse;
+import org.apache.olingo.server.api.ServiceMetadata;
+import org.apache.olingo.server.api.processor.EntityProcessor;
+import org.apache.olingo.server.api.serializer.EntitySerializerOptions;
+import org.apache.olingo.server.api.serializer.ODataSerializer;
+import org.apache.olingo.server.api.serializer.SerializerResult;
+import org.apache.olingo.server.api.uri.UriInfo;
+import org.apache.olingo.server.api.uri.UriParameter;
+import org.apache.olingo.server.api.uri.UriResource;
+import org.apache.olingo.server.api.uri.UriResourceEntitySet;
+import org.apache.olingo.server.api.uri.UriResourceNavigation;
+import org.baeldung.examples.olingo4.repository.EdmEntityRepository;
+import org.baeldung.examples.olingo4.repository.RepositoryRegistry;
+import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.stereotype.Component;
+
+/**
+ * JpaEntityProcessor adapter. 
+ * <p>This implementation is heavily based on the Tutorial available
+ * at Olingo's site. It is meant to be an starting point for an actual implementation.</p>
+ * <p>Please note that many features from a full-fledged are missing
+ * @author Philippe
+ *
+ */
+@Component
+public class JpaEntityProcessor implements EntityProcessor {
+    
+    private EntityManagerFactory emf;
+    private OData odata;
+    private ServiceMetadata serviceMetadata;
+    private RepositoryRegistry registry;
+    private JpaEntityMapper entityMapper;
+
+    public JpaEntityProcessor(EntityManagerFactory emf, RepositoryRegistry registry, JpaEntityMapper entityMapper) {
+        this.emf = emf;
+        this.registry = registry;
+        this.entityMapper = entityMapper;
+    }
+
+    /* (non-Javadoc)
+     * @see org.apache.olingo.server.api.processor.Processor#init(org.apache.olingo.server.api.OData, org.apache.olingo.server.api.ServiceMetadata)
+     */
+    @Override
+    public void init(OData odata, ServiceMetadata serviceMetadata) {
+        this.odata = odata;
+        this.serviceMetadata = serviceMetadata;
+        
+    }
+
+    /* (non-Javadoc)
+     * @see org.apache.olingo.server.api.processor.EntityProcessor#readEntity(org.apache.olingo.server.api.ODataRequest, org.apache.olingo.server.api.ODataResponse, org.apache.olingo.server.api.uri.UriInfo, org.apache.olingo.commons.api.format.ContentType)
+     */
+    @Override
+    public void readEntity(ODataRequest request, ODataResponse response, UriInfo uriInfo, ContentType responseFormat) throws ODataApplicationException, ODataLibraryException {
+
+        // First, we have to figure out which entity is requested
+        List<UriResource> resourceParts = uriInfo.getUriResourceParts();
+        InputStream entityStream;
+        
+        UriResourceEntitySet rootResourceEntitySet = (UriResourceEntitySet) resourceParts.get(0);
+        EdmEntitySet rootEntitySet = rootResourceEntitySet.getEntitySet();        
+        List<UriParameter> rootPredicates = rootResourceEntitySet.getKeyPredicates();
+        
+        if ( resourceParts.size() == 1 ) {
+            entityStream = readRootEntity(rootEntitySet,rootPredicates,responseFormat);
+        }
+        else if ( resourceParts.size() == 2 ) {
+            UriResource part = resourceParts.get(1);
+            if ( !(part instanceof UriResourceNavigation)) {
+                throw new ODataRuntimeException("[E103] part type not supported: class=" + part.getClass().getName());
+            }
+
+            UriResourceNavigation navSegment = (UriResourceNavigation)part;
+            entityStream = readRelatedEntity(request, rootEntitySet,rootPredicates,navSegment.getProperty(),navSegment.getKeyPredicates(),responseFormat);                       
+        }
+        else {
+            // For now, we'll only allow navigation just to directly linked navs
+            throw new ODataApplicationException("[E109] Multi-level navigation not supported", HttpStatusCode.NOT_IMPLEMENTED.getStatusCode(), Locale.ROOT);
+        }
+
+        //4. configure the response object
+        response.setContent(entityStream);
+        response.setStatusCode(HttpStatusCode.OK.getStatusCode());
+        response.setHeader(HttpHeader.CONTENT_TYPE, responseFormat.toContentTypeString());       
+        
+    }
+    
+
+    // Lookup the EntitySet associated with an EntityType
+    // In our example, we assume we have only one entityset for each entity type
+    private EdmEntitySet entitySetFromType(EdmEntityType type) {
+        return serviceMetadata
+          .getEdm()
+          .getEntityContainer()
+          .getEntitySets()
+          .stream()
+          .filter((s) -> s.getEntityType().getName().equals(type.getName()))
+          .findFirst()
+          .orElseThrow(() -> new ODataRuntimeException("[E144] No entity set found for type " + type.getFullQualifiedName()));
+    }
+
+    // 
+   // private boolean isOne2ManyProperty(EdmEntityType entityType, EdmNavigationProperty property) {        
+    //    return entityType.getProperty(property.getName()) != null && property.isCollection();
+    //}
+
+    @SuppressWarnings({ "rawtypes", "unchecked" })
+    private InputStream readRootEntity(EdmEntitySet entitySet, List<UriParameter> keyPredicates,ContentType responseFormat) throws ODataApplicationException, ODataLibraryException {        
+        EdmEntityType type = entitySet.getEntityType();        
+        JpaRepository repo =  registry.getRepositoryForEntity(type);
+        
+        // Get key value
+        Long keyValue =  getEntityKey(keyPredicates);
+        Optional<Object> entry  = repo.findById(keyValue);
+        if ( !entry.isPresent()) {
+            throw new ODataApplicationException(
+              "[E116] NO entity found for the given key",
+              HttpStatusCode.NOT_FOUND.getStatusCode(), 
+              Locale.ENGLISH);
+        }
+      
+        Entity e = entityMapper.map2entity(entitySet, entry.get());        
+        return serializeEntity(entitySet,e,responseFormat);        
+    }
+    
+    private InputStream serializeEntity(EdmEntitySet entitySet, Entity entity,ContentType responseFormat) throws ODataApplicationException, ODataLibraryException {
+        ContextURL contextUrl = ContextURL.with().entitySet(entitySet).build();
+        // expand and select currently not supported
+        EntitySerializerOptions options = EntitySerializerOptions
+          .with()
+          .contextURL(contextUrl)
+          .build();
+
+        ODataSerializer serializer = odata.createSerializer(responseFormat);
+        
+        SerializerResult serializerResult = serializer.entity(serviceMetadata, entitySet.getEntityType(), entity, options);
+        return serializerResult.getContent();
+        
+    }
+    
+//    @SuppressWarnings("unchecked")
+//    protected InputStream readRelatedEntities(EdmEntitySet rootEntitySet, List<UriParameter> rootPredicates, EdmNavigationProperty property, ContentType responseFormat) throws ODataApplicationException {
+//
+//        Object jpaEntity = readJPAEntity(rootEntitySet, rootPredicates);
+//        try {
+//            Collection<Object> set = (Collection<Object>)PropertyUtils.getProperty(jpaEntity, property.getName());
+//            EdmEntitySet entitySet = entitySetFromType(property.getType());
+//            ContextURL contextUrl = ContextURL
+//              .with()
+//              .entitySet(entitySet)
+//              .build();
+//            
+//            EntityCollectionSerializerOptions options = EntityCollectionSerializerOptions
+//              .with()
+//              .contextURL(contextUrl)
+//              .build();
+//            
+//            EntityCollection result = new EntityCollection();
+//            
+//            set.stream()
+//              .map((o) -> this.entityMapper.map2entity(entitySet, o))
+//              .forEach((e) -> result.getEntities().add(e));
+//
+//            ODataSerializer serializer = odata.createSerializer(responseFormat);            
+//            SerializerResult serializerResult = serializer.entityCollection(serviceMetadata, property.getType(), result, options);
+//            return serializerResult.getContent();
+//        }
+//        catch(Exception ex) {
+//            throw new ODataRuntimeException("[E181] Error accessing database", ex);
+//        }
+//    }
+    
+    @SuppressWarnings({ "rawtypes", "unchecked" })
+    private InputStream readRelatedEntity(ODataRequest request, EdmEntitySet entitySet, List<UriParameter> rootPredicates, EdmNavigationProperty property, List<UriParameter> parentPredicates, ContentType responseFormat) throws ODataApplicationException, ODataLibraryException {
+
+
+        JpaRepository<Object,Object> repo =  (JpaRepository<Object,Object>)registry.getRepositoryForEntity(entitySet.getEntityType());
+        EdmEntityRepository<Object> relatedRepo =  (EdmEntityRepository<Object>)registry.getRepositoryForEntity(property.getType());
+
+        // We assume here that we have a bi-directional 1:N relationship, so we'll
+        // always have a property in the child entity that points to the parent
+        Class<?> rootClass = ((EdmEntityRepository)repo).getEntityClass();        
+        Class<?> relatedClass = ((EdmEntityRepository)relatedRepo).getEntityClass();
+        
+        SingularAttribute fk = emf.getMetamodel()
+          .entity(rootClass)
+          .getSingularAttributes()
+          .stream()
+          .filter((attr) -> {
+              boolean b = attr.isAssociation() && attr.getJavaType().isAssignableFrom(relatedClass);
+              return b;
+          })
+          .findFirst()
+          .orElse(null);
+        
+        if ( fk == null ) {
+            throw new ODataRuntimeException("[E230] No singular attribute of child class '" + relatedClass.getName() + "' found" );
+        }
+        
+        Long pkValue = getEntityKey(rootPredicates);  
+        EntityManager em = this.emf.createEntityManager();
+        try {
+            // Read data from DB 
+            Object root = em.find(rootClass, pkValue);            
+            Object related = this.entityMapper.getPropertyValue(root, fk.getName());
+                
+            EdmEntitySet relatedEntitySet = entitySetFromType(property.getType());        
+            Entity e = entityMapper.map2entity(relatedEntitySet, related);               
+            return serializeEntity(relatedEntitySet,e,responseFormat);
+        }
+        finally {
+            em.close();
+        }
+    }
+
+//    @SuppressWarnings("unchecked")
+//    private Object readJPAEntity(EdmEntitySet edmEntitySet, List<UriParameter> keyPredicates) throws ODataApplicationException {
+//        EdmEntityType type = edmEntitySet.getEntityType();        
+//        JpaRepository<Object,Object> repo =  (JpaRepository<Object,Object>)registry.getRepositoryForEntity(type);
+//        
+//        // Get key value
+//        Object keyValue =  getEntityKey(type,keyPredicates);
+//        Object entry = repo
+//          .findById(keyValue)
+//          .orElseThrow(
+//             () -> new ODataApplicationException("[E116] NO entity found for the given key",
+//                                       HttpStatusCode.NOT_FOUND.getStatusCode(), Locale.ENGLISH));
+//       
+//        return entry;
+//    }
+
+    private Long getEntityKey(List<UriParameter> keyPredicates) {
+        
+        if ( keyPredicates.size() > 1 ) {
+            throw new ODataRuntimeException("[E131] Composite keys are not supported");
+        }
+        
+        // For now, we'll assume we only have numeric keys.
+        UriParameter keyParam = keyPredicates.get(0);
+        try {
+            return Long.parseLong(keyParam.getText());
+        }
+        catch(NumberFormatException nfe) {
+            throw new ODataRuntimeException("[E140] Invalid key value. Only numeric keys are supported by this service");
+        }
+        
+        
+    }
+
+    /* (non-Javadoc)
+     * @see org.apache.olingo.server.api.processor.EntityProcessor#createEntity(org.apache.olingo.server.api.ODataRequest, org.apache.olingo.server.api.ODataResponse, org.apache.olingo.server.api.uri.UriInfo, org.apache.olingo.commons.api.format.ContentType, org.apache.olingo.commons.api.format.ContentType)
+     */
+    @Override
+    public void createEntity(ODataRequest request, ODataResponse response, UriInfo uriInfo, ContentType requestFormat, ContentType responseFormat) throws ODataApplicationException, ODataLibraryException {
+        // TODO Auto-generated method stub
+
+    }
+
+    /* (non-Javadoc)
+     * @see org.apache.olingo.server.api.processor.EntityProcessor#updateEntity(org.apache.olingo.server.api.ODataRequest, org.apache.olingo.server.api.ODataResponse, org.apache.olingo.server.api.uri.UriInfo, org.apache.olingo.commons.api.format.ContentType, org.apache.olingo.commons.api.format.ContentType)
+     */
+    @Override
+    public void updateEntity(ODataRequest request, ODataResponse response, UriInfo uriInfo, ContentType requestFormat, ContentType responseFormat) throws ODataApplicationException, ODataLibraryException {
+        // TODO Auto-generated method stub
+
+    }
+
+    /* (non-Javadoc)
+     * @see org.apache.olingo.server.api.processor.EntityProcessor#deleteEntity(org.apache.olingo.server.api.ODataRequest, org.apache.olingo.server.api.ODataResponse, org.apache.olingo.server.api.uri.UriInfo)
+     */
+    @Override
+    public void deleteEntity(ODataRequest request, ODataResponse response, UriInfo uriInfo) throws ODataApplicationException, ODataLibraryException {
+        // TODO Auto-generated method stub
+
+    }
+
+}
diff --git a/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/repository/CarMakerRepository.java b/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/repository/CarMakerRepository.java
new file mode 100644
index 0000000000..1bde9f148c
--- /dev/null
+++ b/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/repository/CarMakerRepository.java
@@ -0,0 +1,16 @@
+package org.baeldung.examples.olingo4.repository;
+
+import org.baeldung.examples.olingo4.domain.CarMaker;
+import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.data.jpa.repository.JpaSpecificationExecutor;
+import org.springframework.stereotype.Repository;
+
+@Repository
+public interface CarMakerRepository extends EdmEntityRepository<CarMaker>, JpaRepository<CarMaker, Long>, JpaSpecificationExecutor<CarMaker> {
+
+    public default String getEdmEntityName() { return CarMaker.class.getSimpleName();}
+    @Override
+    default Class<CarMaker> getEntityClass() {
+        return CarMaker.class;
+    }
+}
diff --git a/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/repository/CarModelRepository.java b/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/repository/CarModelRepository.java
new file mode 100644
index 0000000000..247bf6e77b
--- /dev/null
+++ b/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/repository/CarModelRepository.java
@@ -0,0 +1,22 @@
+package org.baeldung.examples.olingo4.repository;
+
+import java.util.List;
+
+import org.baeldung.examples.olingo4.domain.CarModel;
+import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.data.jpa.repository.JpaSpecificationExecutor;
+import org.springframework.stereotype.Repository;
+
+@Repository
+public interface CarModelRepository extends EdmEntityRepository<CarModel>, JpaRepository<CarModel, Long>, JpaSpecificationExecutor<CarModel> {
+
+    public List<CarModel> findByMakerId(Long makerId);
+    
+    public default String getEdmEntityName() { return CarModel.class.getSimpleName();}
+    
+    @Override
+    default Class<CarModel> getEntityClass() {
+        return CarModel.class;
+    }
+
+}
diff --git a/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/repository/EdmEntityRepository.java b/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/repository/EdmEntityRepository.java
new file mode 100644
index 0000000000..dbfd0e6f93
--- /dev/null
+++ b/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/repository/EdmEntityRepository.java
@@ -0,0 +1,17 @@
+/**
+ * 
+ */
+package org.baeldung.examples.olingo4.repository;
+
+
+/**
+ * @author Philippe
+ *
+ */
+public interface EdmEntityRepository<E>  {
+    
+    public String getEdmEntityName();
+    public Class<E> getEntityClass();
+
+
+}
diff --git a/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/repository/RepositoryRegistry.java b/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/repository/RepositoryRegistry.java
new file mode 100644
index 0000000000..e3bb172e3a
--- /dev/null
+++ b/apache-olingo/olingo4/src/main/java/org/baeldung/examples/olingo4/repository/RepositoryRegistry.java
@@ -0,0 +1,29 @@
+package org.baeldung.examples.olingo4.repository;
+
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+import org.apache.olingo.commons.api.edm.EdmEntityType;
+import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.stereotype.Component;
+
+@Component
+public class RepositoryRegistry {
+    
+    private Map<String,JpaRepository<?,?>> repositoriesByClassName = new HashMap<>();
+
+    public RepositoryRegistry(List<EdmEntityRepository<?>> allRepositories) {
+        
+        allRepositories.stream()
+          .forEach((r) ->  
+            repositoriesByClassName.put(r.getEdmEntityName(),(JpaRepository<?,?>)r));
+        
+    }
+    
+    
+    public JpaRepository<?,?> getRepositoryForEntity(EdmEntityType entityType) {        
+        JpaRepository<?,?> repo = repositoriesByClassName.get(entityType.getName());
+        return repo;
+    }
+}
diff --git a/apache-olingo/olingo4/src/main/resources/application.properties b/apache-olingo/olingo4/src/main/resources/application.properties
new file mode 100644
index 0000000000..02c7fe5c4d
--- /dev/null
+++ b/apache-olingo/olingo4/src/main/resources/application.properties
@@ -0,0 +1,9 @@
+server:
+	port: 8080
+	
+spring:    
+  jpa:
+    show-sql: true
+    open-in-view: true
+    hibernate:
+      ddl-auto: update
diff --git a/apache-olingo/olingo4/src/main/resources/data.sql b/apache-olingo/olingo4/src/main/resources/data.sql
new file mode 100644
index 0000000000..327f2688c5
--- /dev/null
+++ b/apache-olingo/olingo4/src/main/resources/data.sql
@@ -0,0 +1,12 @@
+insert into car_maker(id,name) values (1,'Special Motors');
+insert into car_maker(id,name) values (2,'BWM');
+insert into car_maker(id,name) values (3,'Dolores');
+
+insert into car_model(id,maker_fk,name,sku,year) values(1,1,'Muze','SM001',2018);
+insert into car_model(id,maker_fk,name,sku,year) values(2,1,'Empada','SM002',2008);
+
+insert into car_model(id,maker_fk,name,sku,year) values(4,2,'BWM-100','BWM100',2008);
+insert into car_model(id,maker_fk,name,sku,year) values(5,2,'BWM-200','BWM200',2009);
+insert into car_model(id,maker_fk,name,sku,year) values(6,2,'BWM-300','BWM300',2008);
+
+alter sequence hibernate_sequence restart with 100;
\ No newline at end of file
diff --git a/apache-olingo/olingo4/src/test/java/org/baeldung/examples/olingo4/Olingo4SampleApplicationTests.java b/apache-olingo/olingo4/src/test/java/org/baeldung/examples/olingo4/Olingo4SampleApplicationTests.java
new file mode 100644
index 0000000000..5d23a4148e
--- /dev/null
+++ b/apache-olingo/olingo4/src/test/java/org/baeldung/examples/olingo4/Olingo4SampleApplicationTests.java
@@ -0,0 +1,16 @@
+package org.baeldung.examples.olingo4;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.test.context.junit4.SpringRunner;
+
+@RunWith(SpringRunner.class)
+@SpringBootTest
+public class Olingo4SampleApplicationTests {
+
+	@Test
+	public void contextLoads() {
+	}
+
+}
diff --git a/software-security/sql-injection-samples/pom.xml b/software-security/sql-injection-samples/pom.xml
index b982a34e75..b12b479614 100644
--- a/software-security/sql-injection-samples/pom.xml
+++ b/software-security/sql-injection-samples/pom.xml
@@ -17,6 +17,7 @@
 
 	<dependencies>
 	
+	
 		<dependency>
 			<groupId>org.springframework.boot</groupId>
 			<artifactId>spring-boot-starter-jdbc</artifactId>
@@ -53,6 +54,11 @@
 		    <artifactId>hibernate-jpamodelgen</artifactId>
 		</dependency>
 
+
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-devtools</artifactId>
+		</dependency>
 	</dependencies>
 
 	<build>
diff --git a/spring-webflux-amqp/pom.xml b/spring-webflux-amqp/pom.xml
index a8346458a0..88f5eff403 100755
--- a/spring-webflux-amqp/pom.xml
+++ b/spring-webflux-amqp/pom.xml
@@ -1,62 +1,76 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
-    <modelVersion>4.0.0</modelVersion>
-    <groupId>org.baeldung.spring</groupId>
-    <artifactId>spring-webflux-amqp</artifactId>
-    <version>1.0.0-SNAPSHOT</version>
-    <name>spring-webflux-amqp</name>
-    <packaging>jar</packaging>
-    <description>Spring WebFlux AMQP Sample</description>
+	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+	<modelVersion>4.0.0</modelVersion>
+	<groupId>org.baeldung.spring</groupId>
+	<artifactId>spring-webflux-amqp</artifactId>
+	<version>1.0.0-SNAPSHOT</version>
+	<name>spring-webflux-amqp</name>
+	<packaging>jar</packaging>
+	<description>Spring WebFlux AMQP Sample</description>
 
-    <parent>
-        <artifactId>parent-boot-2</artifactId>
-        <groupId>com.baeldung</groupId>
-        <version>0.0.1-SNAPSHOT</version>
-        <relativePath>../parent-boot-2</relativePath>
-    </parent>
+	<parent>
+		<artifactId>parent-boot-2</artifactId>
+		<groupId>com.baeldung</groupId>
+		<version>0.0.1-SNAPSHOT</version>
+		<relativePath>../parent-boot-2</relativePath>
+	</parent>
 
-    <dependencies>
-        <dependency>
-            <groupId>org.springframework.boot</groupId>
-            <artifactId>spring-boot-starter-amqp</artifactId>
-        </dependency>
-        <dependency>
-            <groupId>org.springframework.boot</groupId>
-            <artifactId>spring-boot-starter-webflux</artifactId>
-        </dependency>
+	<dependencyManagement>
+		<dependencies>
+			<dependency>
+				<!-- Import dependency management from Spring Boot -->
+				<groupId>org.springframework.boot</groupId>
+				<artifactId>spring-boot-dependencies</artifactId>
+				<!-- <version>2.0.4.RELEASE</version>  --><!-- works -->
+				<version>2.1.3.RELEASE</version>  <!-- Works with workaround applied -->
+				<type>pom</type>
+				<scope>import</scope>
+			</dependency>
+		</dependencies>
+	</dependencyManagement>
 
-        <dependency>
-            <groupId>org.springframework.boot</groupId>
-            <artifactId>spring-boot-configuration-processor</artifactId>
-            <optional>true</optional>
-        </dependency>
+	<dependencies>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-amqp</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-webflux</artifactId>
+		</dependency>
 
-        <dependency>
-            <groupId>org.springframework.boot</groupId>
-            <artifactId>spring-boot-starter-test</artifactId>
-            <scope>test</scope>
-        </dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-configuration-processor</artifactId>
+			<optional>true</optional>
+		</dependency>
 
-        <dependency>
-            <groupId>io.projectreactor</groupId>
-            <artifactId>reactor-test</artifactId>
-            <scope>test</scope>
-        </dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-test</artifactId>
+			<scope>test</scope>
+		</dependency>
 
-        <dependency>
-            <groupId>org.springframework.boot</groupId>
-            <artifactId>spring-boot-starter-integration</artifactId>
-        </dependency>
-    </dependencies>
+		<dependency>
+			<groupId>io.projectreactor</groupId>
+			<artifactId>reactor-test</artifactId>
+			<scope>test</scope>
+		</dependency>
 
-    <build>
-        <plugins>
-            <plugin>
-                <groupId>org.springframework.boot</groupId>
-                <artifactId>spring-boot-maven-plugin</artifactId>
-            </plugin>
-        </plugins>
-    </build>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-integration</artifactId>
+		</dependency>
+	</dependencies>
+
+	<build>
+		<plugins>
+			<plugin>
+				<groupId>org.springframework.boot</groupId>
+				<artifactId>spring-boot-maven-plugin</artifactId>
+			</plugin>
+		</plugins>
+	</build>
 
 </project>
diff --git a/spring-webflux-amqp/src/main/java/org/baeldung/spring/amqp/SpringWebfluxAmqpApplication.java b/spring-webflux-amqp/src/main/java/org/baeldung/spring/amqp/SpringWebfluxAmqpApplication.java
index 30614e7ee6..8a31299333 100755
--- a/spring-webflux-amqp/src/main/java/org/baeldung/spring/amqp/SpringWebfluxAmqpApplication.java
+++ b/spring-webflux-amqp/src/main/java/org/baeldung/spring/amqp/SpringWebfluxAmqpApplication.java
@@ -3,6 +3,12 @@ package org.baeldung.spring.amqp;
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
 import org.springframework.boot.context.properties.EnableConfigurationProperties;
+import org.springframework.context.annotation.Bean;
+import org.springframework.web.filter.reactive.HiddenHttpMethodFilter;
+import org.springframework.web.server.ServerWebExchange;
+import org.springframework.web.server.WebFilterChain;
+
+import reactor.core.publisher.Mono;
 
 @SpringBootApplication
 @EnableConfigurationProperties(DestinationsConfig.class)
@@ -12,4 +18,19 @@ public class SpringWebfluxAmqpApplication {
         SpringApplication.run(SpringWebfluxAmqpApplication.class, args);
     }
     
+    
+    /**
+     * This is a workaround for https://github.com/spring-projects/spring-framework/issues/21094
+     * @return
+     */
+    @Bean
+    public HiddenHttpMethodFilter hiddenHttpMethodFilter() {
+        return new HiddenHttpMethodFilter() {
+            @Override
+            public Mono<Void> filter(ServerWebExchange exchange, WebFilterChain chain) {
+                return chain.filter(exchange);
+            }
+        };
+    }
+    
 }
diff --git a/spring-webflux-amqp/src/main/resources/application.yml b/spring-webflux-amqp/src/main/resources/application.yml
index 702aaba357..3f527ce4c5 100755
--- a/spring-webflux-amqp/src/main/resources/application.yml
+++ b/spring-webflux-amqp/src/main/resources/application.yml
@@ -1,6 +1,6 @@
 spring:
   rabbitmq:
-    host: localhost
+    host: 192.168.99.100
     port: 5672
     username: guest
     password: guest