Merge pull request #273 from ajibade3210/nodeGraphql

Node graphql

build-all.sh

@@ -87,6 +87,8 @@ if [[ "$MODULE" == "module7" ]]
 then
   # ADD NEW MODULES HERE
   # (add new modules above the rest so you get quicker feedback if it fails)
+  build_gradle_module "kotlin/coroutines"
+  build_maven_module "core-java/streams/data-streams"
   build maven_module "aws/kinesis"
   build maven_module "aws/sqs"
   build_maven_module "core-java/annotation-processing/introduction-to-annotations"

core-java/jackson/jackson/.gitignore

@@ -0,0 +1,29 @@
+HELP.md
+target/*
+!.mvn/wrapper/maven-wrapper.jar
+!**/src/main/**/target/
+!**/src/test/**/target/
+
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+
+### IntelliJ IDEA ###
+.idea
+*.iws
+*.iml
+*.ipr
+
+### NetBeans ###
+/nbproject/private/
+/nbbuild/
+/dist/
+/nbdist/
+build/
+!**/src/main/**/build/
+!**/src/test/**/build/
+
+### VS Code ###
+.vscode/

core-java/jackson/jackson/pom.xml

@@ -0,0 +1,52 @@
+<?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>com.reflectoring</groupId>
+    <artifactId>jackson</artifactId>
+    <version>1.0-SNAPSHOT</version>
+
+    <properties>
+        <maven.compiler.source>11</maven.compiler.source>
+        <maven.compiler.target>11</maven.compiler.target>
+    </properties>
+
+    <dependencies>
+        <dependency>
+            <groupId>com.fasterxml.jackson.core</groupId>
+            <artifactId>jackson-databind</artifactId>
+            <version>2.13.3</version>
+        </dependency>
+
+        <dependency>
+            <groupId>com.fasterxml.jackson.datatype</groupId>
+            <artifactId>jackson-datatype-jsr310</artifactId>
+            <version>2.13.3</version>
+        </dependency>
+
+        <dependency>
+            <groupId>org.junit.jupiter</groupId>
+            <artifactId>junit-jupiter-api</artifactId>
+            <version>5.9.0-M1</version>
+            <scope>test</scope>
+        </dependency>
+
+        <dependency>
+            <groupId>org.projectlombok</groupId>
+            <artifactId>lombok</artifactId>
+            <version>1.18.24</version>
+            <scope>provided</scope>
+        </dependency>
+
+        <dependency>
+            <groupId>org.assertj</groupId>
+            <artifactId>assertj-core</artifactId>
+            <version>3.23.1</version>
+            <scope>test</scope>
+        </dependency>
+
+
+    </dependencies>
+</project>

core-java/jackson/jackson/src/main/java/com/reflectoring/pojo/Car.java

@@ -0,0 +1,24 @@
+package com.reflectoring.pojo;
+
+import com.fasterxml.jackson.annotation.JsonAnySetter;
+import com.fasterxml.jackson.annotation.JsonSetter;
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+
+import java.util.HashMap;
+import java.util.Map;
+
+@NoArgsConstructor
+@AllArgsConstructor
+@Getter
+public class Car {
+    @JsonSetter("carBrand")
+    private String brand;
+    private Map<String, String> unrecognizedFields = new HashMap<>();
+
+    @JsonAnySetter
+    public void allSetter(String fieldName, String fieldValue) {
+        unrecognizedFields.put(fieldName, fieldValue);
+    }
+}

core-java/jackson/jackson/src/main/java/com/reflectoring/pojo/Cat.java

@@ -0,0 +1,29 @@
+package com.reflectoring.pojo;
+
+import com.fasterxml.jackson.annotation.JsonAnyGetter;
+import com.fasterxml.jackson.annotation.JsonGetter;
+import lombok.AllArgsConstructor;
+import lombok.NoArgsConstructor;
+
+import java.util.Map;
+
+@NoArgsConstructor
+@AllArgsConstructor
+public class Cat {
+    private String name;
+
+    @JsonAnyGetter
+    Map<String, String> map = Map.of(
+            "name", "Jack",
+            "surname", "wolfskin"
+    );
+
+    @JsonGetter("catName")
+    public String getName() {
+        return name;
+    }
+
+    public Cat(String name) {
+        this.name = name;
+    }
+}

core-java/jackson/jackson/src/main/java/com/reflectoring/pojo/Dog.java

@@ -0,0 +1,15 @@
+package com.reflectoring.pojo;
+
+import com.fasterxml.jackson.annotation.JsonIgnore;
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+
+@AllArgsConstructor
+@NoArgsConstructor
+@Getter
+public class Dog {
+    private String name;
+    @JsonIgnore
+    private Integer age;
+}

core-java/jackson/jackson/src/main/java/com/reflectoring/pojo/Employee.java

@@ -0,0 +1,16 @@
+package com.reflectoring.pojo;
+
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+
+import java.util.Date;
+
+@Getter
+@AllArgsConstructor
+@NoArgsConstructor
+public class Employee {
+    private String firstName;
+    private String lastName;
+    private int age;
+}

core-java/jackson/jackson/src/main/java/com/reflectoring/pojo/Order.java

@@ -0,0 +1,18 @@
+package com.reflectoring.pojo;
+
+import com.fasterxml.jackson.annotation.JsonFormat;
+import com.fasterxml.jackson.annotation.JsonSetter;
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+
+import java.time.LocalDate;
+
+@NoArgsConstructor
+@AllArgsConstructor
+@Getter
+public class Order {
+    private int id;
+    @JsonFormat(pattern = "dd/MM/yyyy")
+    private LocalDate date;
+}

core-java/jackson/jackson/src/test/java/com/reflectoring/JacksonTest.java

@@ -0,0 +1,184 @@
+package com.reflectoring;
+
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.core.type.TypeReference;
+import com.fasterxml.jackson.databind.DeserializationFeature;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.reflectoring.pojo.*;
+import org.junit.jupiter.api.Test;
+
+import java.io.File;
+import java.io.IOException;
+import java.time.LocalDate;
+import java.util.List;
+import java.util.Map;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+public class JacksonTest {
+    ObjectMapper objectMapper = new ObjectMapper().findAndRegisterModules();
+
+    @Test
+    void jsonStringToPojo() throws JsonProcessingException {
+        String employeeJson = "{\n" +
+                " \"firstName\" : \"Jalil\",\n" +
+                "  \"lastName\" : \"Jarjanazy\",\n" +
+                "  \"age\" : 30\n" +
+                "}";
+
+        Employee employee = objectMapper.readValue(employeeJson, Employee.class);
+
+        assertThat(employee.getFirstName()).isEqualTo("Jalil");
+    }
+
+    @Test
+    void pojoToJsonString() throws JsonProcessingException {
+        Employee employee = new Employee("Mark", "James", 20);
+
+        String json = objectMapper.writeValueAsString(employee);
+
+        assertThat(json).isEqualTo("{\"firstName\":\"Mark\",\"lastName\":\"James\",\"age\":20}");
+    }
+
+    @Test
+    void jsonFileToPojo() throws IOException {
+        File file = new File("src/test/resources/employee.json");
+
+        Employee employee = objectMapper.readValue(file, Employee.class);
+
+        assertThat(employee.getAge()).isEqualTo(44);
+        assertThat(employee.getLastName()).isEqualTo("Simpson");
+        assertThat(employee.getFirstName()).isEqualTo("Homer");
+    }
+
+    @Test
+    void byteArrayToPojo() throws IOException {
+        String employeeJson = "{\n" +
+                " \"firstName\" : \"Jalil\",\n" +
+                "  \"lastName\" : \"Jarjanazy\",\n" +
+                "  \"age\" : 30\n" +
+                "}";
+
+        Employee employee = objectMapper.readValue(employeeJson.getBytes(), Employee.class);
+
+        assertThat(employee.getFirstName()).isEqualTo("Jalil");
+    }
+
+    @Test
+    void fileToListOfPojos() throws IOException {
+        File file = new File("src/test/resources/employeeList.json");
+        List<Employee> employeeList = objectMapper.readValue(file, new TypeReference<>(){});
+
+        assertThat(employeeList).hasSize(2);
+        assertThat(employeeList.get(0).getAge()).isEqualTo(33);
+        assertThat(employeeList.get(0).getLastName()).isEqualTo("Simpson");
+        assertThat(employeeList.get(0).getFirstName()).isEqualTo("Marge");
+    }
+
+    @Test
+    void fileToMap() throws IOException {
+        File file = new File("src/test/resources/employee.json");
+        Map<String, Object> employee = objectMapper.readValue(file, new TypeReference<>(){});
+
+        assertThat(employee.keySet()).containsExactly("firstName", "lastName", "age");
+
+        assertThat(employee.get("firstName")).isEqualTo("Homer");
+        assertThat(employee.get("lastName")).isEqualTo("Simpson");
+        assertThat(employee.get("age")).isEqualTo(44);
+    }
+
+    @Test
+    void fileToPojoWithUnknownProperties() throws IOException {
+        File file = new File("src/test/resources/employeeWithUnknownProperties.json");
+
+        objectMapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);
+
+        Employee employee = objectMapper.readValue(file, Employee.class);
+
+        assertThat(employee.getFirstName()).isEqualTo("Homer");
+        assertThat(employee.getLastName()).isEqualTo("Simpson");
+        assertThat(employee.getAge()).isEqualTo(44);
+    }
+
+    @Test
+    void orderToJson() throws JsonProcessingException {
+        Order order = new Order(1, LocalDate.of(1900,2,1));
+
+        String json = objectMapper.writeValueAsString(order);
+
+        System.out.println(json);
+    }
+
+    @Test
+    void orderToJsonWithDate() throws JsonProcessingException {
+        Order order = new Order(1, LocalDate.of(2023, 1, 1));
+
+        String json = objectMapper.writeValueAsString(order);
+
+        System.out.println(json);
+    }
+    @Test
+    void fileToOrder() throws IOException {
+        File file = new File("src/test/resources/order.json");
+
+        Order order = objectMapper.readValue(file, Order.class);
+
+        assertThat(order.getDate().getYear()).isEqualTo(2000);
+        assertThat(order.getDate().getMonthValue()).isEqualTo(4);
+        assertThat(order.getDate().getDayOfMonth()).isEqualTo(30);
+    }
+    @Test
+    void fileToCar() throws IOException {
+        File file = new File("src/test/resources/car.json");
+
+        Car car = objectMapper.readValue(file, Car.class);
+
+        assertThat(car.getBrand()).isEqualTo("BMW");
+    }
+
+    @Test
+    void fileToUnrecognizedCar() throws IOException {
+        File file = new File("src/test/resources/carUnrecognized.json");
+
+        Car car = objectMapper.readValue(file, Car.class);
+
+        assertThat(car.getUnrecognizedFields()).containsKey("productionYear");
+    }
+
+    @Test
+    void catToJson() throws JsonProcessingException {
+        Cat cat = new Cat("Monica");
+
+        String json = objectMapper.writeValueAsString(cat);
+
+        System.out.println(json);
+
+    }
+
+    @Test
+    void catToJsonWithMap() throws JsonProcessingException {
+        Cat cat = new Cat("Monica");
+
+        String json = objectMapper.writeValueAsString(cat);
+
+        System.out.println(json);
+    }
+
+    @Test
+    void dogToJson() throws JsonProcessingException {
+        Dog dog = new Dog("Max", 3);
+
+        String json = objectMapper.writeValueAsString(dog);
+
+        System.out.println(json);
+    }
+    @Test
+    void fileToDog() throws IOException {
+        File file = new File("src/test/resources/dog.json");
+
+        Dog dog = objectMapper.readValue(file, Dog.class);
+
+        assertThat(dog.getName()).isEqualTo("bobby");
+        assertThat(dog.getAge()).isNull();
+    }
+}

core-java/jackson/jackson/src/test/resources/car.json

@@ -0,0 +1,3 @@
+{
+  "carBrand" : "BMW"
+}

core-java/jackson/jackson/src/test/resources/carUnrecognized.json

@@ -0,0 +1,4 @@
+{
+  "carBrand" : "BMW",
+  "productionYear": 1996
+}

core-java/jackson/jackson/src/test/resources/dog.json

@@ -0,0 +1,4 @@
+{
+  "name" : "bobby",
+  "age" : 5
+}

core-java/jackson/jackson/src/test/resources/employee.json

@@ -0,0 +1,5 @@
+{
+  "firstName":"Homer",
+  "lastName":"Simpson",
+  "age":44
+}

core-java/jackson/jackson/src/test/resources/employeeList.json

@@ -0,0 +1,12 @@
+[
+  {
+    "firstName":"Marge",
+    "lastName":"Simpson",
+    "age":33
+  },
+  {
+  "firstName":"Homer",
+  "lastName":"Simpson",
+  "age":44
+  }
+]

core-java/jackson/jackson/src/test/resources/employeeWithUnknownProperties.json

@@ -0,0 +1,6 @@
+{
+  "firstName":"Homer",
+  "lastName":"Simpson",
+  "age":44,
+  "department": "IT"
+}

core-java/jackson/jackson/src/test/resources/order.json

@@ -0,0 +1,4 @@
+{
+  "id" : 1,
+  "date" : "30/04/2000"
+}

core-java/junit5-parameterized-tests/.gitignore

@@ -0,0 +1,8 @@
+# Maven 
+target/
+.mvn/
+
+# eclipse project file
+.settings/
+.classpath
+.project

core-java/junit5-parameterized-tests/README.md

@@ -0,0 +1,3 @@
+# Related Blog Posts
+
+* [Parameterized tests with JUnit 5](https://reflectoring.io/junit5-parameterized-tests/)

core-java/junit5-parameterized-tests/mvnw

@@ -0,0 +1,287 @@
+#!/bin/sh
+# ----------------------------------------------------------------------------
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+# ----------------------------------------------------------------------------
+
+# ----------------------------------------------------------------------------
+# Apache Maven Wrapper startup batch script, version 3.1.1
+#
+# Required ENV vars:
+# ------------------
+#   JAVA_HOME - location of a JDK home dir
+#
+# Optional ENV vars
+# -----------------
+#   MAVEN_OPTS - parameters passed to the Java VM when running Maven
+#     e.g. to debug Maven itself, use
+#       set MAVEN_OPTS=-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=8000
+#   MAVEN_SKIP_RC - flag to disable loading of mavenrc files
+# ----------------------------------------------------------------------------
+
+if [ -z "$MAVEN_SKIP_RC" ] ; then
+
+  if [ -f /usr/local/etc/mavenrc ] ; then
+    . /usr/local/etc/mavenrc
+  fi
+
+  if [ -f /etc/mavenrc ] ; then
+    . /etc/mavenrc
+  fi
+
+  if [ -f "$HOME/.mavenrc" ] ; then
+    . "$HOME/.mavenrc"
+  fi
+
+fi
+
+# OS specific support.  $var _must_ be set to either true or false.
+cygwin=false;
+darwin=false;
+mingw=false
+case "`uname`" in
+  CYGWIN*) cygwin=true ;;
+  MINGW*) mingw=true;;
+  Darwin*) darwin=true
+    # Use /usr/libexec/java_home if available, otherwise fall back to /Library/Java/Home
+    # See https://developer.apple.com/library/mac/qa/qa1170/_index.html
+    if [ -z "$JAVA_HOME" ]; then
+      if [ -x "/usr/libexec/java_home" ]; then
+        JAVA_HOME="`/usr/libexec/java_home`"; export JAVA_HOME
+      else
+        JAVA_HOME="/Library/Java/Home"; export JAVA_HOME
+      fi
+    fi
+    ;;
+esac
+
+if [ -z "$JAVA_HOME" ] ; then
+  if [ -r /etc/gentoo-release ] ; then
+    JAVA_HOME=`java-config --jre-home`
+  fi
+fi
+
+# For Cygwin, ensure paths are in UNIX format before anything is touched
+if $cygwin ; then
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME=`cygpath --unix "$JAVA_HOME"`
+  [ -n "$CLASSPATH" ] &&
+    CLASSPATH=`cygpath --path --unix "$CLASSPATH"`
+fi
+
+# For Mingw, ensure paths are in UNIX format before anything is touched
+if $mingw ; then
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME="`(cd "$JAVA_HOME"; pwd)`"
+fi
+
+if [ -z "$JAVA_HOME" ]; then
+  javaExecutable="`which javac`"
+  if [ -n "$javaExecutable" ] && ! [ "`expr \"$javaExecutable\" : '\([^ ]*\)'`" = "no" ]; then
+    # readlink(1) is not available as standard on Solaris 10.
+    readLink=`which readlink`
+    if [ ! `expr "$readLink" : '\([^ ]*\)'` = "no" ]; then
+      if $darwin ; then
+        javaHome="`dirname \"$javaExecutable\"`"
+        javaExecutable="`cd \"$javaHome\" && pwd -P`/javac"
+      else
+        javaExecutable="`readlink -f \"$javaExecutable\"`"
+      fi
+      javaHome="`dirname \"$javaExecutable\"`"
+      javaHome=`expr "$javaHome" : '\(.*\)/bin'`
+      JAVA_HOME="$javaHome"
+      export JAVA_HOME
+    fi
+  fi
+fi
+
+if [ -z "$JAVACMD" ] ; then
+  if [ -n "$JAVA_HOME"  ] ; then
+    if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
+      # IBM's JDK on AIX uses strange locations for the executables
+      JAVACMD="$JAVA_HOME/jre/sh/java"
+    else
+      JAVACMD="$JAVA_HOME/bin/java"
+    fi
+  else
+    JAVACMD="`\\unset -f command; \\command -v java`"
+  fi
+fi
+
+if [ ! -x "$JAVACMD" ] ; then
+  echo "Error: JAVA_HOME is not defined correctly." >&2
+  echo "  We cannot execute $JAVACMD" >&2
+  exit 1
+fi
+
+if [ -z "$JAVA_HOME" ] ; then
+  echo "Warning: JAVA_HOME environment variable is not set."
+fi
+
+# traverses directory structure from process work directory to filesystem root
+# first directory with .mvn subdirectory is considered project base directory
+find_maven_basedir() {
+  if [ -z "$1" ]
+  then
+    echo "Path not specified to find_maven_basedir"
+    return 1
+  fi
+
+  basedir="$1"
+  wdir="$1"
+  while [ "$wdir" != '/' ] ; do
+    if [ -d "$wdir"/.mvn ] ; then
+      basedir=$wdir
+      break
+    fi
+    # workaround for JBEAP-8937 (on Solaris 10/Sparc)
+    if [ -d "${wdir}" ]; then
+      wdir=`cd "$wdir/.."; pwd`
+    fi
+    # end of workaround
+  done
+  printf '%s' "$(cd "$basedir"; pwd)"
+}
+
+# concatenates all lines of a file
+concat_lines() {
+  if [ -f "$1" ]; then
+    echo "$(tr -s '\n' ' ' < "$1")"
+  fi
+}
+
+BASE_DIR=$(find_maven_basedir "$(dirname $0)")
+if [ -z "$BASE_DIR" ]; then
+  exit 1;
+fi
+
+MAVEN_PROJECTBASEDIR=${MAVEN_BASEDIR:-"$BASE_DIR"}; export MAVEN_PROJECTBASEDIR
+if [ "$MVNW_VERBOSE" = true ]; then
+  echo $MAVEN_PROJECTBASEDIR
+fi
+
+##########################################################################################
+# Extension to allow automatically downloading the maven-wrapper.jar from Maven-central
+# This allows using the maven wrapper in projects that prohibit checking in binary data.
+##########################################################################################
+if [ -r "$BASE_DIR/.mvn/wrapper/maven-wrapper.jar" ]; then
+    if [ "$MVNW_VERBOSE" = true ]; then
+      echo "Found .mvn/wrapper/maven-wrapper.jar"
+    fi
+else
+    if [ "$MVNW_VERBOSE" = true ]; then
+      echo "Couldn't find .mvn/wrapper/maven-wrapper.jar, downloading it ..."
+    fi
+    if [ -n "$MVNW_REPOURL" ]; then
+      wrapperUrl="$MVNW_REPOURL/org/apache/maven/wrapper/maven-wrapper/3.1.1/maven-wrapper-3.1.1.jar"
+    else
+      wrapperUrl="https://repo.maven.apache.org/maven2/org/apache/maven/wrapper/maven-wrapper/3.1.1/maven-wrapper-3.1.1.jar"
+    fi
+    while IFS="=" read key value; do
+      case "$key" in (wrapperUrl) wrapperUrl="$value"; break ;;
+      esac
+    done < "$BASE_DIR/.mvn/wrapper/maven-wrapper.properties"
+    if [ "$MVNW_VERBOSE" = true ]; then
+      echo "Downloading from: $wrapperUrl"
+    fi
+    wrapperJarPath="$BASE_DIR/.mvn/wrapper/maven-wrapper.jar"
+    if $cygwin; then
+      wrapperJarPath=`cygpath --path --windows "$wrapperJarPath"`
+    fi
+
+    if command -v wget > /dev/null; then
+        QUIET="--quiet"
+        if [ "$MVNW_VERBOSE" = true ]; then
+          echo "Found wget ... using wget"
+          QUIET=""
+        fi
+        if [ -z "$MVNW_USERNAME" ] || [ -z "$MVNW_PASSWORD" ]; then
+            wget $QUIET "$wrapperUrl" -O "$wrapperJarPath"
+        else
+            wget $QUIET --http-user="$MVNW_USERNAME" --http-password="$MVNW_PASSWORD" "$wrapperUrl" -O "$wrapperJarPath"
+        fi
+        [ $? -eq 0 ] || rm -f "$wrapperJarPath"
+    elif command -v curl > /dev/null; then
+        QUIET="--silent"
+        if [ "$MVNW_VERBOSE" = true ]; then
+          echo "Found curl ... using curl"
+          QUIET=""
+        fi
+        if [ -z "$MVNW_USERNAME" ] || [ -z "$MVNW_PASSWORD" ]; then
+            curl $QUIET -o "$wrapperJarPath" "$wrapperUrl" -f -L
+        else
+            curl $QUIET --user "$MVNW_USERNAME:$MVNW_PASSWORD" -o "$wrapperJarPath" "$wrapperUrl" -f -L
+        fi
+        [ $? -eq 0 ] || rm -f "$wrapperJarPath"
+    else
+        if [ "$MVNW_VERBOSE" = true ]; then
+          echo "Falling back to using Java to download"
+        fi
+        javaSource="$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.java"
+        javaClass="$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.class"
+        # For Cygwin, switch paths to Windows format before running javac
+        if $cygwin; then
+          javaSource=`cygpath --path --windows "$javaSource"`
+          javaClass=`cygpath --path --windows "$javaClass"`
+        fi
+        if [ -e "$javaSource" ]; then
+            if [ ! -e "$javaClass" ]; then
+                if [ "$MVNW_VERBOSE" = true ]; then
+                  echo " - Compiling MavenWrapperDownloader.java ..."
+                fi
+                # Compiling the Java class
+                ("$JAVA_HOME/bin/javac" "$javaSource")
+            fi
+            if [ -e "$javaClass" ]; then
+                # Running the downloader
+                if [ "$MVNW_VERBOSE" = true ]; then
+                  echo " - Running MavenWrapperDownloader.java ..."
+                fi
+                ("$JAVA_HOME/bin/java" -cp .mvn/wrapper MavenWrapperDownloader "$MAVEN_PROJECTBASEDIR")
+            fi
+        fi
+    fi
+fi
+##########################################################################################
+# End of extension
+##########################################################################################
+
+MAVEN_OPTS="$(concat_lines "$MAVEN_PROJECTBASEDIR/.mvn/jvm.config") $MAVEN_OPTS"
+
+# For Cygwin, switch paths to Windows format before running java
+if $cygwin; then
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME=`cygpath --path --windows "$JAVA_HOME"`
+  [ -n "$CLASSPATH" ] &&
+    CLASSPATH=`cygpath --path --windows "$CLASSPATH"`
+  [ -n "$MAVEN_PROJECTBASEDIR" ] &&
+    MAVEN_PROJECTBASEDIR=`cygpath --path --windows "$MAVEN_PROJECTBASEDIR"`
+fi
+
+# Provide a "standardized" way to retrieve the CLI args that will
+# work with both Windows and non-Windows executions.
+MAVEN_CMD_LINE_ARGS="$MAVEN_CONFIG $@"
+export MAVEN_CMD_LINE_ARGS
+
+WRAPPER_LAUNCHER=org.apache.maven.wrapper.MavenWrapperMain
+
+exec "$JAVACMD" \
+  $MAVEN_OPTS \
+  $MAVEN_DEBUG_OPTS \
+  -classpath "$MAVEN_PROJECTBASEDIR/.mvn/wrapper/maven-wrapper.jar" \
+  "-Dmaven.multiModuleProjectDirectory=${MAVEN_PROJECTBASEDIR}" \
+  ${WRAPPER_LAUNCHER} $MAVEN_CONFIG "$@"

core-java/junit5-parameterized-tests/mvnw.cmd

@@ -0,0 +1,187 @@
+@REM ----------------------------------------------------------------------------
+@REM Licensed to the Apache Software Foundation (ASF) under one
+@REM or more contributor license agreements.  See the NOTICE file
+@REM distributed with this work for additional information
+@REM regarding copyright ownership.  The ASF licenses this file
+@REM to you under the Apache License, Version 2.0 (the
+@REM "License"); you may not use this file except in compliance
+@REM with the License.  You may obtain a copy of the License at
+@REM
+@REM    http://www.apache.org/licenses/LICENSE-2.0
+@REM
+@REM Unless required by applicable law or agreed to in writing,
+@REM software distributed under the License is distributed on an
+@REM "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+@REM KIND, either express or implied.  See the License for the
+@REM specific language governing permissions and limitations
+@REM under the License.
+@REM ----------------------------------------------------------------------------
+
+@REM ----------------------------------------------------------------------------
+@REM Apache Maven Wrapper startup batch script, version 3.1.1
+@REM
+@REM Required ENV vars:
+@REM JAVA_HOME - location of a JDK home dir
+@REM
+@REM Optional ENV vars
+@REM MAVEN_BATCH_ECHO - set to 'on' to enable the echoing of the batch commands
+@REM MAVEN_BATCH_PAUSE - set to 'on' to wait for a keystroke before ending
+@REM MAVEN_OPTS - parameters passed to the Java VM when running Maven
+@REM     e.g. to debug Maven itself, use
+@REM set MAVEN_OPTS=-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=8000
+@REM MAVEN_SKIP_RC - flag to disable loading of mavenrc files
+@REM ----------------------------------------------------------------------------
+
+@REM Begin all REM lines with '@' in case MAVEN_BATCH_ECHO is 'on'
+@echo off
+@REM set title of command window
+title %0
+@REM enable echoing by setting MAVEN_BATCH_ECHO to 'on'
+@if "%MAVEN_BATCH_ECHO%" == "on"  echo %MAVEN_BATCH_ECHO%
+
+@REM set %HOME% to equivalent of $HOME
+if "%HOME%" == "" (set "HOME=%HOMEDRIVE%%HOMEPATH%")
+
+@REM Execute a user defined script before this one
+if not "%MAVEN_SKIP_RC%" == "" goto skipRcPre
+@REM check for pre script, once with legacy .bat ending and once with .cmd ending
+if exist "%USERPROFILE%\mavenrc_pre.bat" call "%USERPROFILE%\mavenrc_pre.bat" %*
+if exist "%USERPROFILE%\mavenrc_pre.cmd" call "%USERPROFILE%\mavenrc_pre.cmd" %*
+:skipRcPre
+
+@setlocal
+
+set ERROR_CODE=0
+
+@REM To isolate internal variables from possible post scripts, we use another setlocal
+@setlocal
+
+@REM ==== START VALIDATION ====
+if not "%JAVA_HOME%" == "" goto OkJHome
+
+echo.
+echo Error: JAVA_HOME not found in your environment. >&2
+echo Please set the JAVA_HOME variable in your environment to match the >&2
+echo location of your Java installation. >&2
+echo.
+goto error
+
+:OkJHome
+if exist "%JAVA_HOME%\bin\java.exe" goto init
+
+echo.
+echo Error: JAVA_HOME is set to an invalid directory. >&2
+echo JAVA_HOME = "%JAVA_HOME%" >&2
+echo Please set the JAVA_HOME variable in your environment to match the >&2
+echo location of your Java installation. >&2
+echo.
+goto error
+
+@REM ==== END VALIDATION ====
+
+:init
+
+@REM Find the project base dir, i.e. the directory that contains the folder ".mvn".
+@REM Fallback to current working directory if not found.
+
+set MAVEN_PROJECTBASEDIR=%MAVEN_BASEDIR%
+IF NOT "%MAVEN_PROJECTBASEDIR%"=="" goto endDetectBaseDir
+
+set EXEC_DIR=%CD%
+set WDIR=%EXEC_DIR%
+:findBaseDir
+IF EXIST "%WDIR%"\.mvn goto baseDirFound
+cd ..
+IF "%WDIR%"=="%CD%" goto baseDirNotFound
+set WDIR=%CD%
+goto findBaseDir
+
+:baseDirFound
+set MAVEN_PROJECTBASEDIR=%WDIR%
+cd "%EXEC_DIR%"
+goto endDetectBaseDir
+
+:baseDirNotFound
+set MAVEN_PROJECTBASEDIR=%EXEC_DIR%
+cd "%EXEC_DIR%"
+
+:endDetectBaseDir
+
+IF NOT EXIST "%MAVEN_PROJECTBASEDIR%\.mvn\jvm.config" goto endReadAdditionalConfig
+
+@setlocal EnableExtensions EnableDelayedExpansion
+for /F "usebackq delims=" %%a in ("%MAVEN_PROJECTBASEDIR%\.mvn\jvm.config") do set JVM_CONFIG_MAVEN_PROPS=!JVM_CONFIG_MAVEN_PROPS! %%a
+@endlocal & set JVM_CONFIG_MAVEN_PROPS=%JVM_CONFIG_MAVEN_PROPS%
+
+:endReadAdditionalConfig
+
+SET MAVEN_JAVA_EXE="%JAVA_HOME%\bin\java.exe"
+set WRAPPER_JAR="%MAVEN_PROJECTBASEDIR%\.mvn\wrapper\maven-wrapper.jar"
+set WRAPPER_LAUNCHER=org.apache.maven.wrapper.MavenWrapperMain
+
+set WRAPPER_URL="https://repo.maven.apache.org/maven2/org/apache/maven/wrapper/maven-wrapper/3.1.1/maven-wrapper-3.1.1.jar"
+
+FOR /F "usebackq tokens=1,2 delims==" %%A IN ("%MAVEN_PROJECTBASEDIR%\.mvn\wrapper\maven-wrapper.properties") DO (
+    IF "%%A"=="wrapperUrl" SET WRAPPER_URL=%%B
+)
+
+@REM Extension to allow automatically downloading the maven-wrapper.jar from Maven-central
+@REM This allows using the maven wrapper in projects that prohibit checking in binary data.
+if exist %WRAPPER_JAR% (
+    if "%MVNW_VERBOSE%" == "true" (
+        echo Found %WRAPPER_JAR%
+    )
+) else (
+    if not "%MVNW_REPOURL%" == "" (
+        SET WRAPPER_URL="%MVNW_REPOURL%/org/apache/maven/wrapper/maven-wrapper/3.1.1/maven-wrapper-3.1.1.jar"
+    )
+    if "%MVNW_VERBOSE%" == "true" (
+        echo Couldn't find %WRAPPER_JAR%, downloading it ...
+        echo Downloading from: %WRAPPER_URL%
+    )
+
+    powershell -Command "&{"^
+		"$webclient = new-object System.Net.WebClient;"^
+		"if (-not ([string]::IsNullOrEmpty('%MVNW_USERNAME%') -and [string]::IsNullOrEmpty('%MVNW_PASSWORD%'))) {"^
+		"$webclient.Credentials = new-object System.Net.NetworkCredential('%MVNW_USERNAME%', '%MVNW_PASSWORD%');"^
+		"}"^
+		"[Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12; $webclient.DownloadFile('%WRAPPER_URL%', '%WRAPPER_JAR%')"^
+		"}"
+    if "%MVNW_VERBOSE%" == "true" (
+        echo Finished downloading %WRAPPER_JAR%
+    )
+)
+@REM End of extension
+
+@REM Provide a "standardized" way to retrieve the CLI args that will
+@REM work with both Windows and non-Windows executions.
+set MAVEN_CMD_LINE_ARGS=%*
+
+%MAVEN_JAVA_EXE% ^
+  %JVM_CONFIG_MAVEN_PROPS% ^
+  %MAVEN_OPTS% ^
+  %MAVEN_DEBUG_OPTS% ^
+  -classpath %WRAPPER_JAR% ^
+  "-Dmaven.multiModuleProjectDirectory=%MAVEN_PROJECTBASEDIR%" ^
+  %WRAPPER_LAUNCHER% %MAVEN_CONFIG% %*
+if ERRORLEVEL 1 goto error
+goto end
+
+:error
+set ERROR_CODE=1
+
+:end
+@endlocal & set ERROR_CODE=%ERROR_CODE%
+
+if not "%MAVEN_SKIP_RC%"=="" goto skipRcPost
+@REM check for post script, once with legacy .bat ending and once with .cmd ending
+if exist "%USERPROFILE%\mavenrc_post.bat" call "%USERPROFILE%\mavenrc_post.bat"
+if exist "%USERPROFILE%\mavenrc_post.cmd" call "%USERPROFILE%\mavenrc_post.cmd"
+:skipRcPost
+
+@REM pause the script if MAVEN_BATCH_PAUSE is set to 'on'
+if "%MAVEN_BATCH_PAUSE%"=="on" pause
+
+if "%MAVEN_TERMINATE_CMD%"=="on" exit %ERROR_CODE%
+
+cmd /C exit /B %ERROR_CODE%

core-java/junit5-parameterized-tests/pom.xml

@@ -0,0 +1,33 @@
+<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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+	<modelVersion>4.0.0</modelVersion>
+	<groupId>io.refactoring</groupId>
+	<artifactId>junit5-parameterized-tests</artifactId>
+	<version>1.0.0-SNAPSHOT</version>
+	<properties>
+        <maven.compiler.source>11</maven.compiler.source>
+        <maven.compiler.target>11</maven.compiler.target>
+        
+		<junit-jupiter-params.version>5.9.2</junit-jupiter-params.version>
+		<commons-lang3.version>3.12.0</commons-lang3.version>
+		<assertj-core>3.24.1</assertj-core>
+	</properties>
+    
+	<dependencies>
+		<!-- https://mvnrepository.com/artifact/org.junit.jupiter/junit-jupiter-params -->
+		<dependency>
+			<groupId>org.junit.jupiter</groupId>
+			<artifactId>junit-jupiter-params</artifactId>
+			<version>${junit-jupiter-params.version}</version>
+			<scope>test</scope>
+		</dependency>
+		
+		<!-- https://mvnrepository.com/artifact/org.apache.commons/commons-lang3 -->
+		<dependency>
+			<groupId>org.apache.commons</groupId>
+			<artifactId>commons-lang3</artifactId>
+			<version>${commons-lang3.version}</version>
+		</dependency>
+		
+	</dependencies>
+	
+</project>

core-java/junit5-parameterized-tests/src/test/java/source/argument/conversion/ArgumentConversionTest.java

@@ -0,0 +1,43 @@
+package source.argument.conversion;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+
+import java.time.temporal.ChronoUnit;
+
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.converter.ConvertWith;
+import org.junit.jupiter.params.provider.ValueSource;
+
+public class ArgumentConversionTest {
+
+	@ParameterizedTest
+	@ValueSource(ints = { 2, 4 })
+	void checkWideningArgumentConversion(long number) {
+		assertEquals(0, number % 2);
+	}
+
+	// ---------------------------------------------------------------------------
+
+	@ParameterizedTest
+	@ValueSource(strings = "DAYS")
+	void checkImplicitArgumentConversion(ChronoUnit argument) {
+		assertNotNull(argument.name());
+	}
+
+	// ---------------------------------------------------------------------------
+
+	@ParameterizedTest
+	@ValueSource(strings = { "Name1", "Name2" })
+	void checkImplicitFallbackArgumentConversion(Person person) {
+		assertNotNull(person.getName());
+	}
+
+	// ---------------------------------------------------------------------------
+
+	@ParameterizedTest
+	@ValueSource(ints = { 100 })
+	void checkExplicitArgumentConversion(@ConvertWith(StringSimpleArgumentConverter.class) String argument) {
+		assertEquals("100", argument);
+	}
+}

core-java/junit5-parameterized-tests/src/test/java/source/argument/conversion/Person.java

@@ -0,0 +1,18 @@
+package source.argument.conversion;
+
+public class Person {
+
+	private String name;
+
+	public Person(String name) {
+		this.name = name;
+	}
+
+	public String getName() {
+		return name;
+	}
+
+	public void setName(String name) {
+		this.name = name;
+	}
+}

core-java/junit5-parameterized-tests/src/test/java/source/argument/conversion/StringSimpleArgumentConverter.java

@@ -0,0 +1,13 @@
+package source.argument.conversion;
+
+import org.junit.jupiter.params.converter.ArgumentConversionException;
+import org.junit.jupiter.params.converter.SimpleArgumentConverter;
+
+public class StringSimpleArgumentConverter extends SimpleArgumentConverter {
+
+	@Override
+	protected Object convert(Object source, Class<?> targetType) throws ArgumentConversionException {
+		return String.valueOf(source);
+	}
+
+}

core-java/junit5-parameterized-tests/src/test/java/source/arguments/ArgumentsSourceTest.java

@@ -0,0 +1,39 @@
+package source.arguments;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import java.util.stream.Stream;
+
+import org.apache.commons.lang3.StringUtils;
+import org.junit.jupiter.api.extension.ExtensionContext;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.Arguments;
+import org.junit.jupiter.params.provider.ArgumentsProvider;
+import org.junit.jupiter.params.provider.ArgumentsSource;
+
+public class ArgumentsSourceTest {
+
+	@ParameterizedTest
+	@ArgumentsSource(ExternalArgumentsProvider.class)
+	void checkExternalArgumentsSource(int number, String expected) {
+		assertEquals(StringUtils.equals(expected, "even") ? 0 : 1, number % 2,
+				"Supplied number " + number + " is not an " + expected + " number");
+	}
+
+	// ---------------------------------------------------------------------------
+
+	@ParameterizedTest
+	@ArgumentsSource(NestedArgumentsProvider.class)
+	void checkNestedArgumentsSource(int number, String expected) {
+		assertEquals(StringUtils.equals(expected, "even") ? 0 : 1, number % 2,
+				"Supplied number " + number + " is not an " + expected + " number");
+	}
+
+	static class NestedArgumentsProvider implements ArgumentsProvider {
+
+		@Override
+		public Stream<? extends Arguments> provideArguments(ExtensionContext context) throws Exception {
+			return Stream.of(Arguments.of(2, "even"), Arguments.of(3, "odd"));
+		}
+	}
+}

core-java/junit5-parameterized-tests/src/test/java/source/arguments/ExternalArgumentsProvider.java

@@ -0,0 +1,16 @@
+package source.arguments;
+
+import java.util.stream.Stream;
+
+import org.junit.jupiter.api.extension.ExtensionContext;
+import org.junit.jupiter.params.provider.Arguments;
+import org.junit.jupiter.params.provider.ArgumentsProvider;
+
+public class ExternalArgumentsProvider implements ArgumentsProvider {
+
+	@Override
+	public Stream<? extends Arguments> provideArguments(ExtensionContext context) throws Exception {
+		return Stream.of(Arguments.of(2, "even"), 
+						 Arguments.of(3, "odd"));
+	}
+}

core-java/junit5-parameterized-tests/src/test/java/source/arguments/aggregator/ArgumentsAccessorTest.java

@@ -0,0 +1,18 @@
+package source.arguments.aggregator;
+
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.aggregator.ArgumentsAccessor;
+import org.junit.jupiter.params.provider.CsvSource;
+
+public class ArgumentsAccessorTest {
+
+	@ParameterizedTest
+	@CsvSource({ "John, 20", 
+				 "Harry, 30" })
+	void checkArgumentsAccessor(ArgumentsAccessor arguments) {
+		Person person = new Person(arguments.getString(0), arguments.getInteger(1));
+		assertTrue(person.getAge() > 19, person.getName() + " is a teenager");
+	}
+}

core-java/junit5-parameterized-tests/src/test/java/source/arguments/aggregator/ArgumentsAggregatorTest.java

@@ -0,0 +1,24 @@
+package source.arguments.aggregator;
+
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.aggregator.AggregateWith;
+import org.junit.jupiter.params.provider.CsvSource;
+
+public class ArgumentsAggregatorTest {
+
+	@ParameterizedTest
+	@CsvSource({ "John, 20", "Harry, 30" })
+	void checkArgumentsAggregator(@AggregateWith(PersonArgumentsAggregator.class) Person person) {
+		assertTrue(person.getAge() > 19, person.getName() + " is a teenager");
+	}
+
+	// ---------------------------------------------------------------------------
+
+	@ParameterizedTest
+	@CsvSource({ "John, 20", "Harry, 30" })
+	void checkCustomAggregatorAnnotation(@CsvToPerson Person person) {
+		assertTrue(person.getAge() > 19, person.getName() + " is a teenager");
+	}
+}

core-java/junit5-parameterized-tests/src/test/java/source/arguments/aggregator/CsvToPerson.java

@@ -0,0 +1,15 @@
+package source.arguments.aggregator;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+import org.junit.jupiter.params.aggregator.AggregateWith;
+
+@Retention(RetentionPolicy.RUNTIME)
+@Target(ElementType.PARAMETER)
+@AggregateWith(PersonArgumentsAggregator.class)
+public @interface CsvToPerson {
+
+}

core-java/junit5-parameterized-tests/src/test/java/source/arguments/aggregator/Person.java

@@ -0,0 +1,30 @@
+package source.arguments.aggregator;
+
+public class Person {
+
+	private String name;
+
+	private int age;
+
+	public Person(String name, int age) {
+		this.name = name;
+		this.age = age;
+	}
+
+	public String getName() {
+		return name;
+	}
+
+	public void setName(String name) {
+		this.name = name;
+	}
+
+	public int getAge() {
+		return age;
+	}
+
+	public void setAge(int age) {
+		this.age = age;
+	}
+
+}

core-java/junit5-parameterized-tests/src/test/java/source/arguments/aggregator/PersonArgumentsAggregator.java

@@ -0,0 +1,16 @@
+package source.arguments.aggregator;
+
+import org.junit.jupiter.api.extension.ParameterContext;
+import org.junit.jupiter.params.aggregator.ArgumentsAccessor;
+import org.junit.jupiter.params.aggregator.ArgumentsAggregationException;
+import org.junit.jupiter.params.aggregator.ArgumentsAggregator;
+
+public class PersonArgumentsAggregator implements ArgumentsAggregator {
+
+	@Override
+	public Object aggregateArguments(ArgumentsAccessor arguments, ParameterContext context)
+			throws ArgumentsAggregationException {
+		return new Person(arguments.getString(0), arguments.getInteger(1));
+	}
+
+}

core-java/junit5-parameterized-tests/src/test/java/source/assertj/AssertJTest.java

@@ -0,0 +1,27 @@
+package source.assertj;
+
+import java.util.function.Consumer;
+import java.util.stream.Stream;
+
+import org.assertj.core.api.Assertions;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.Arguments;
+import org.junit.jupiter.params.provider.MethodSource;
+
+public class AssertJTest {
+
+	@ParameterizedTest
+	@MethodSource("checkNumberArgs")
+	void checkNumber(int number, Consumer<Integer> consumer) {
+
+		consumer.accept(number);
+	}
+
+	static Stream<Arguments> checkNumberArgs() {
+
+		Consumer<Integer> evenConsumer = i -> Assertions.assertThat(i % 2).isZero();
+		Consumer<Integer> oddConsumer = i -> Assertions.assertThat(i % 2).isEqualTo(1);
+
+		return Stream.of(Arguments.of(2, evenConsumer), Arguments.of(3, oddConsumer));
+	}
+}

core-java/junit5-parameterized-tests/src/test/java/source/csv/CsvSourceTest.java

@@ -0,0 +1,17 @@
+package source.csv;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import org.apache.commons.lang3.StringUtils;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.CsvSource;
+
+public class CsvSourceTest {
+
+	@ParameterizedTest
+	@CsvSource({ "2, even", 
+				 "3, odd"})
+	void checkCsvSource(int number, String expected) {
+		assertEquals(StringUtils.equals(expected, "even") ? 0 : 1, number % 2);
+	}
+}

core-java/junit5-parameterized-tests/src/test/java/source/csv/file/CsvFileSourceTest.java

@@ -0,0 +1,27 @@
+package source.csv.file;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import org.apache.commons.lang3.StringUtils;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.CsvFileSource;
+
+public class CsvFileSourceTest {
+
+	@ParameterizedTest
+	@CsvFileSource(files = "src/test/resources/csv-file-source.csv", numLinesToSkip = 1)
+	void checkCsvFileSource(int number, String expected) {
+		assertEquals(StringUtils.equals(expected, "even") ? 0 : 1, number % 2);
+	}
+
+	// ---------------------------------------------------------------------------
+
+	@ParameterizedTest
+	@CsvFileSource(files = "src/test/resources/csv-file-source_attributes.csv", 
+				   delimiterString = "|",
+				   lineSeparator = "||",
+				   numLinesToSkip = 1)
+	void checkCsvFileSourceAttributes(int number, String expected) {
+		assertEquals(StringUtils.equals(expected, "even") ? 0 : 1, number % 2);
+	}
+}

core-java/junit5-parameterized-tests/src/test/java/source/enumeration/EnumSourceTest.java

@@ -0,0 +1,25 @@
+package source.enumeration;
+
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+
+import java.time.temporal.ChronoUnit;
+
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.EnumSource;
+
+public class EnumSourceTest {
+
+	@ParameterizedTest
+	@EnumSource(ChronoUnit.class)
+	void checkEnumSourceValue(ChronoUnit unit) {
+		assertNotNull(unit);
+	}
+
+	// ---------------------------------------------------------------------------
+
+	@ParameterizedTest
+	@EnumSource(names = { "DAYS", "HOURS" })
+	void checkEnumSourceNames(ChronoUnit unit) {
+		assertNotNull(unit);
+	}
+}

core-java/junit5-parameterized-tests/src/test/java/source/method/ExternalMethodSource.java

@@ -0,0 +1,11 @@
+package source.method;
+
+import java.util.stream.Stream;
+
+public class ExternalMethodSource {
+
+	static Stream<String> checkExternalMethodSourceArgs() {
+		return Stream.of("a1", "b2");
+	}
+
+}

core-java/junit5-parameterized-tests/src/test/java/source/method/ExternalMethodSourceTest.java

@@ -0,0 +1,17 @@
+package source.method;
+
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import org.apache.commons.lang3.StringUtils;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.MethodSource;
+
+public class ExternalMethodSourceTest {
+
+	// Note: The test will try to load the external method
+	@ParameterizedTest
+	@MethodSource("source.method.ExternalMethodSource#checkExternalMethodSourceArgs")
+	void checkExternalMethodSource(String word) {
+		assertTrue(StringUtils.isAlphanumeric(word), "Supplied word is not alpha-numeric");
+	}
+}

core-java/junit5-parameterized-tests/src/test/java/source/method/MethodSourceTest.java

@@ -0,0 +1,52 @@
+package source.method;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import java.util.stream.Stream;
+
+import org.apache.commons.lang3.StringUtils;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.Arguments;
+import org.junit.jupiter.params.provider.MethodSource;
+
+public class MethodSourceTest {
+
+	// Note: The test will try to load the supplied method
+	@ParameterizedTest
+	@MethodSource("checkExplicitMethodSourceArgs")
+	void checkExplicitMethodSource(String word) {
+		assertTrue(StringUtils.isAlphanumeric(word), "Supplied word is not alpha-numeric");
+	}
+
+	static Stream<String> checkExplicitMethodSourceArgs() {
+		return Stream.of("a1", "b2");
+	}
+
+	// ---------------------------------------------------------------------------
+
+	// Note: The test will search for the source method that matches the test-case
+	// method name
+	@ParameterizedTest
+	@MethodSource
+	void checkImplicitMethodSource(String word) {
+		assertTrue(StringUtils.isAlphanumeric(word), "Supplied word is not alpha-numeric");
+	}
+
+	static Stream<String> checkImplicitMethodSource() {
+		return Stream.of("a1", "b2");
+	}
+
+	// ---------------------------------------------------------------------------
+
+	// Note: The test will automatically map arguments based on the index
+	@ParameterizedTest
+	@MethodSource
+	void checkMultiArgumentsMethodSource(int number, String expected) {
+		assertEquals(StringUtils.equals(expected, "even") ? 0 : 1, number % 2);
+	}
+
+	static Stream<Arguments> checkMultiArgumentsMethodSource() {
+		return Stream.of(Arguments.of(2, "even"), Arguments.of(3, "odd"));
+	}
+}

core-java/junit5-parameterized-tests/src/test/java/source/null_empty/NullEmptySourceTest.java

@@ -0,0 +1,44 @@
+package source.null_empty;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.EmptySource;
+import org.junit.jupiter.params.provider.NullAndEmptySource;
+import org.junit.jupiter.params.provider.NullSource;
+import org.junit.jupiter.params.provider.ValueSource;
+
+public class NullEmptySourceTest {
+
+	@ParameterizedTest
+	@NullSource
+	void checkNull(String value) {
+		assertEquals(null, value);
+	}
+
+	// ---------------------------------------------------------------------------
+
+	@ParameterizedTest
+	@EmptySource
+	void checkEmpty(String value) {
+		assertEquals("", value);
+	}
+
+	// ---------------------------------------------------------------------------
+
+	@ParameterizedTest
+	@NullAndEmptySource
+	void checkNullAndEmpty(String value) {
+		assertTrue(value == null || value.isEmpty());
+	}
+
+	// ---------------------------------------------------------------------------
+
+	@ParameterizedTest
+	@NullAndEmptySource
+	@ValueSource(strings = { " ", "   " })
+	void checkNullEmptyAndBlank(String value) {
+		assertTrue(value == null || value.isBlank());
+	}
+}

core-java/junit5-parameterized-tests/src/test/java/source/value/ValueSourceTest.java

@@ -0,0 +1,25 @@
+package source.value;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import org.apache.commons.lang3.StringUtils;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.ValueSource;
+
+public class ValueSourceTest {
+
+	@ParameterizedTest
+	@ValueSource(ints = { 2, 4 })
+	void checkEvenNumber(int number) {
+		assertEquals(0, number % 2, "Supplied number is not an even number");
+	}
+
+	// ---------------------------------------------------------------------------
+
+	@ParameterizedTest
+	@ValueSource(strings = { "a1", "b2" })
+	void checkAlphanumeric(String word) {
+		assertTrue(StringUtils.isAlphanumeric(word), "Supplied word is not alpha-numeric");
+	}
+}

core-java/junit5-parameterized-tests/src/test/resources/csv-file-source.csv

@@ -0,0 +1,3 @@
+NUMBER, ODD_EVEN
+2, even
+3, odd

core-java/junit5-parameterized-tests/src/test/resources/csv-file-source_attributes.csv

@@ -0,0 +1,3 @@
+|| NUMBER | ODD_EVEN ||
+|| 2 	  | even     ||
+|| 3 	  | odd	     ||

core-java/retrofit/introduction-to-retrofit/AuditApplication/.gitignore

@@ -0,0 +1,2 @@
+# Project exclude paths
+/target/

core-java/retrofit/introduction-to-retrofit/AuditApplication/.mvn/wrapper/MavenWrapperDownloader.java

@@ -0,0 +1,117 @@
+/*
+ * Copyright 2007-present the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+import java.net.*;
+import java.io.*;
+import java.nio.channels.*;
+import java.util.Properties;
+
+public class MavenWrapperDownloader {
+
+    private static final String WRAPPER_VERSION = "0.5.6";
+    /**
+     * Default URL to download the maven-wrapper.jar from, if no 'downloadUrl' is provided.
+     */
+    private static final String DEFAULT_DOWNLOAD_URL = "https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/"
+        + WRAPPER_VERSION + "/maven-wrapper-" + WRAPPER_VERSION + ".jar";
+
+    /**
+     * Path to the maven-wrapper.properties file, which might contain a downloadUrl property to
+     * use instead of the default one.
+     */
+    private static final String MAVEN_WRAPPER_PROPERTIES_PATH =
+            ".mvn/wrapper/maven-wrapper.properties";
+
+    /**
+     * Path where the maven-wrapper.jar will be saved to.
+     */
+    private static final String MAVEN_WRAPPER_JAR_PATH =
+            ".mvn/wrapper/maven-wrapper.jar";
+
+    /**
+     * Name of the property which should be used to override the default download url for the wrapper.
+     */
+    private static final String PROPERTY_NAME_WRAPPER_URL = "wrapperUrl";
+
+    public static void main(String args[]) {
+        System.out.println("- Downloader started");
+        File baseDirectory = new File(args[0]);
+        System.out.println("- Using base directory: " + baseDirectory.getAbsolutePath());
+
+        // If the maven-wrapper.properties exists, read it and check if it contains a custom
+        // wrapperUrl parameter.
+        File mavenWrapperPropertyFile = new File(baseDirectory, MAVEN_WRAPPER_PROPERTIES_PATH);
+        String url = DEFAULT_DOWNLOAD_URL;
+        if(mavenWrapperPropertyFile.exists()) {
+            FileInputStream mavenWrapperPropertyFileInputStream = null;
+            try {
+                mavenWrapperPropertyFileInputStream = new FileInputStream(mavenWrapperPropertyFile);
+                Properties mavenWrapperProperties = new Properties();
+                mavenWrapperProperties.load(mavenWrapperPropertyFileInputStream);
+                url = mavenWrapperProperties.getProperty(PROPERTY_NAME_WRAPPER_URL, url);
+            } catch (IOException e) {
+                System.out.println("- ERROR loading '" + MAVEN_WRAPPER_PROPERTIES_PATH + "'");
+            } finally {
+                try {
+                    if(mavenWrapperPropertyFileInputStream != null) {
+                        mavenWrapperPropertyFileInputStream.close();
+                    }
+                } catch (IOException e) {
+                    // Ignore ...
+                }
+            }
+        }
+        System.out.println("- Downloading from: " + url);
+
+        File outputFile = new File(baseDirectory.getAbsolutePath(), MAVEN_WRAPPER_JAR_PATH);
+        if(!outputFile.getParentFile().exists()) {
+            if(!outputFile.getParentFile().mkdirs()) {
+                System.out.println(
+                        "- ERROR creating output directory '" + outputFile.getParentFile().getAbsolutePath() + "'");
+            }
+        }
+        System.out.println("- Downloading to: " + outputFile.getAbsolutePath());
+        try {
+            downloadFileFromURL(url, outputFile);
+            System.out.println("Done");
+            System.exit(0);
+        } catch (Throwable e) {
+            System.out.println("- Error downloading");
+            e.printStackTrace();
+            System.exit(1);
+        }
+    }
+
+    private static void downloadFileFromURL(String urlString, File destination) throws Exception {
+        if (System.getenv("MVNW_USERNAME") != null && System.getenv("MVNW_PASSWORD") != null) {
+            String username = System.getenv("MVNW_USERNAME");
+            char[] password = System.getenv("MVNW_PASSWORD").toCharArray();
+            Authenticator.setDefault(new Authenticator() {
+                @Override
+                protected PasswordAuthentication getPasswordAuthentication() {
+                    return new PasswordAuthentication(username, password);
+                }
+            });
+        }
+        URL website = new URL(urlString);
+        ReadableByteChannel rbc;
+        rbc = Channels.newChannel(website.openStream());
+        FileOutputStream fos = new FileOutputStream(destination);
+        fos.getChannel().transferFrom(rbc, 0, Long.MAX_VALUE);
+        fos.close();
+        rbc.close();
+    }
+
+}

core-java/retrofit/introduction-to-retrofit/AuditApplication/.mvn/wrapper/maven-wrapper.properties

@@ -0,0 +1,2 @@
+distributionUrl=https://repo.maven.apache.org/maven2/org/apache/maven/apache-maven/3.6.3/apache-maven-3.6.3-bin.zip
+wrapperUrl=https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar

core-java/retrofit/introduction-to-retrofit/AuditApplication/README.md

@@ -0,0 +1,39 @@
+# A simple Spring Boot Audit application
+This application manages auditing of the Library application 
+
+## Details
+ * This application uses the in memory HSQLDB to call the Library application maintain audit logs of the calls made.
+ * It uses Spring Boot to create REST endpoints
+ * It uses Retrofit to make calls to the Library application
+ * It uses Maven and Java11 to build and run.
+
+## How to run
+ * Clone this project
+ * Use maven command: `mvn clean verify spring-boot:run`
+ * The application should run at `http://localhost:8081`
+ * Use POSTMAN to make REST calls
+
+## Sample request JSON body
+
+# POST Sample
+````json
+{
+"bookName": "The Da Vinci Code",
+"publisher": "Corgie Adult",
+"publicationYear": "2009",
+"isCopyrighted": true,
+"authors": [{
+"name": "Dan Brown",
+"dob" : "22/06/1964"
+}]
+}
+````
+
+# PUT Sample
+````json
+{
+    "bookName": "The Da Vinci Code",
+    "publisher": "Corgie Adult - 01",
+    "publicationYear": "2010"
+}
+````

core-java/retrofit/introduction-to-retrofit/AuditApplication/checkstyle-suppressions.xml

@@ -0,0 +1,7 @@
+<?xml version="1.0"?>
+<!DOCTYPE suppressions PUBLIC
+        "-//Checkstyle//DTD SuppressionFilter Configuration 1.2//EN"
+        "https://checkstyle.org/dtds/suppressions_1_2.dtd">
+<suppressions>
+    <suppress files="[/\\]target[/\\]generated-sources[/\\]" checks=".*" />
+</suppressions>

core-java/retrofit/introduction-to-retrofit/AuditApplication/checkstyle.xml

@@ -0,0 +1,246 @@
+<?xml version="1.0"?>
+<!DOCTYPE module PUBLIC
+        "-//Checkstyle//DTD Checkstyle Configuration 1.3//EN"
+        "https://checkstyle.org/dtds/configuration_1_3.dtd">
+
+<module name="Checker">
+    <property name="charset" value="UTF-8"/>
+
+    <property name="severity" value="error"/>
+
+    <property name="fileExtensions" value="java, properties, xml"/>
+
+    <module name="BeforeExecutionExclusionFileFilter">
+        <property name="fileNamePattern" value="module\-info\.java$"/>
+    </module>
+
+    <module name="FileTabCharacter">
+        <property name="eachLine" value="true"/>
+    </module>
+
+    <module name="LineLength">
+        <property name="max" value="120"/>
+        <property name="ignorePattern" value="^package.*|^import.*|a href|href|http://|https://|ftp://"/>
+    </module>
+
+    <module name="TreeWalker">
+        <module name="OuterTypeFilename"/>
+        <module name="IllegalTokenText">
+            <property name="tokens" value="STRING_LITERAL, CHAR_LITERAL"/>
+            <property name="format"
+                      value="\\u00(09|0(a|A)|0(c|C)|0(d|D)|22|27|5(C|c))|\\(0(10|11|12|14|15|42|47)|134)"/>
+            <property name="message"
+                      value="Consider using special escape sequence instead of octal value or Unicode escaped value."/>
+        </module>
+        <module name="AvoidEscapedUnicodeCharacters">
+            <property name="allowEscapesForControlCharacters" value="true"/>
+            <property name="allowByTailComment" value="true"/>
+            <property name="allowNonPrintableEscapes" value="true"/>
+        </module>
+        <module name="OneTopLevelClass"/>
+        <module name="NoLineWrap"/>
+        <module name="EmptyBlock">
+            <property name="option" value="TEXT"/>
+            <property name="tokens"
+                      value="LITERAL_TRY, LITERAL_FINALLY, LITERAL_IF, LITERAL_ELSE, LITERAL_SWITCH"/>
+        </module>
+        <module name="LeftCurly"/>
+        <module name="RightCurly">
+            <property name="id" value="RightCurlySame"/>
+            <property name="tokens"
+                      value="LITERAL_TRY, LITERAL_CATCH, LITERAL_FINALLY, LITERAL_IF, LITERAL_ELSE,
+                    LITERAL_DO"/>
+        </module>
+        <module name="RightCurly">
+            <property name="id" value="RightCurlyAlone"/>
+            <property name="option" value="alone"/>
+            <property name="tokens"
+                      value="CLASS_DEF, METHOD_DEF, CTOR_DEF, LITERAL_FOR, LITERAL_WHILE, STATIC_INIT,
+                    INSTANCE_INIT"/>
+        </module>
+        <module name="WhitespaceAround">
+            <property name="allowEmptyConstructors" value="true"/>
+            <property name="allowEmptyLambdas" value="true"/>
+            <property name="allowEmptyMethods" value="true"/>
+            <property name="allowEmptyTypes" value="true"/>
+            <property name="allowEmptyLoops" value="true"/>
+            <message key="ws.notFollowed"
+                     value="WhitespaceAround: ''{0}'' is not followed by whitespace. Empty blocks may only be represented as '{}' when not part of a multi-block statement (4.1.3)"/>
+            <message key="ws.notPreceded"
+                     value="WhitespaceAround: ''{0}'' is not preceded with whitespace."/>
+        </module>
+        <module name="OneStatementPerLine"/>
+        <module name="MultipleVariableDeclarations"/>
+        <module name="ArrayTypeStyle"/>
+        <module name="MissingSwitchDefault"/>
+        <module name="FallThrough"/>
+        <module name="UpperEll"/>
+        <module name="ModifierOrder"/>
+        <module name="SeparatorWrap">
+            <property name="id" value="SeparatorWrapDot"/>
+            <property name="tokens" value="DOT"/>
+            <property name="option" value="nl"/>
+        </module>
+        <module name="SeparatorWrap">
+            <property name="id" value="SeparatorWrapComma"/>
+            <property name="tokens" value="COMMA"/>
+            <property name="option" value="EOL"/>
+        </module>
+        <module name="SeparatorWrap">
+            <!-- ELLIPSIS is EOL until https://github.com/google/styleguide/issues/258 -->
+            <property name="id" value="SeparatorWrapEllipsis"/>
+            <property name="tokens" value="ELLIPSIS"/>
+            <property name="option" value="EOL"/>
+        </module>
+        <module name="SeparatorWrap">
+            <!-- ARRAY_DECLARATOR is EOL until https://github.com/google/styleguide/issues/259 -->
+            <property name="id" value="SeparatorWrapArrayDeclarator"/>
+            <property name="tokens" value="ARRAY_DECLARATOR"/>
+            <property name="option" value="EOL"/>
+        </module>
+        <module name="SeparatorWrap">
+            <property name="id" value="SeparatorWrapMethodRef"/>
+            <property name="tokens" value="METHOD_REF"/>
+            <property name="option" value="nl"/>
+        </module>
+        <module name="PackageName">
+            <property name="format" value="^[a-z]+(\.[a-z][a-z0-9]*)*$"/>
+            <message key="name.invalidPattern"
+                     value="Package name ''{0}'' must match pattern ''{1}''."/>
+        </module>
+        <module name="TypeName">
+            <message key="name.invalidPattern"
+                     value="Type name ''{0}'' must match pattern ''{1}''."/>
+        </module>
+        <module name="MemberName">
+            <property name="format" value="^[a-z][a-z0-9][a-zA-Z0-9]*$"/>
+            <message key="name.invalidPattern"
+                     value="Member name ''{0}'' must match pattern ''{1}''."/>
+        </module>
+        <module name="ParameterName">
+            <property name="format" value="^[a-z]([a-z0-9][a-zA-Z0-9]*)?$"/>
+            <message key="name.invalidPattern"
+                     value="Parameter name ''{0}'' must match pattern ''{1}''."/>
+        </module>
+        <module name="ParameterNumber"/>
+        <module name="LambdaParameterName">
+            <property name="format" value="^[a-z]([a-z0-9][a-zA-Z0-9]*)?$"/>
+            <message key="name.invalidPattern"
+                     value="Lambda parameter name ''{0}'' must match pattern ''{1}''."/>
+        </module>
+        <module name="CatchParameterName">
+            <property name="format" value="^[a-z]([a-z0-9][a-zA-Z0-9]*)?$"/>
+            <message key="name.invalidPattern"
+                     value="Catch parameter name ''{0}'' must match pattern ''{1}''."/>
+        </module>
+        <module name="LocalVariableName">
+            <property name="tokens" value="VARIABLE_DEF"/>
+            <property name="format" value="^[a-z]([a-z0-9][a-zA-Z0-9]*)?$"/>
+            <message key="name.invalidPattern"
+                     value="Local variable name ''{0}'' must match pattern ''{1}''."/>
+        </module>
+        <module name="ClassTypeParameterName">
+            <property name="format" value="(^[A-Z][0-9]?)$|([A-Z][a-zA-Z0-9]*[T]$)"/>
+            <message key="name.invalidPattern"
+                     value="Class type name ''{0}'' must match pattern ''{1}''."/>
+        </module>
+        <module name="MethodTypeParameterName">
+            <property name="format" value="(^[A-Z][0-9]?)$|([A-Z][a-zA-Z0-9]*[T]$)"/>
+            <message key="name.invalidPattern"
+                     value="Method type name ''{0}'' must match pattern ''{1}''."/>
+        </module>
+        <module name="InterfaceTypeParameterName">
+            <property name="format" value="(^[A-Z][0-9]?)$|([A-Z][a-zA-Z0-9]*[T]$)"/>
+            <message key="name.invalidPattern"
+                     value="Interface type name ''{0}'' must match pattern ''{1}''."/>
+        </module>
+        <module name="NoFinalizer"/>
+        <module name="GenericWhitespace">
+            <message key="ws.followed"
+                     value="GenericWhitespace ''{0}'' is followed by whitespace."/>
+            <message key="ws.preceded"
+                     value="GenericWhitespace ''{0}'' is preceded with whitespace."/>
+            <message key="ws.illegalFollow"
+                     value="GenericWhitespace ''{0}'' should followed by whitespace."/>
+            <message key="ws.notPreceded"
+                     value="GenericWhitespace ''{0}'' is not preceded with whitespace."/>
+        </module>
+        <module name="Indentation">
+            <property name="basicOffset" value="4"/>
+            <property name="braceAdjustment" value="0"/>
+            <property name="caseIndent" value="4"/>
+            <property name="throwsIndent" value="8"/>
+            <property name="lineWrappingIndentation" value="8"/>
+            <property name="arrayInitIndent" value="4"/>
+        </module>
+        <module name="AbbreviationAsWordInName">
+            <property name="ignoreFinal" value="false"/>
+            <property name="allowedAbbreviationLength" value="1"/>
+        </module>
+        <module name="OverloadMethodsDeclarationOrder"/>
+        <module name="VariableDeclarationUsageDistance"/>
+        <module name="CustomImportOrder">
+            <property name="customImportOrderRules"
+                      value="THIRD_PARTY_PACKAGE###SPECIAL_IMPORTS###STANDARD_JAVA_PACKAGE###STATIC"/>
+            <property name="specialImportsRegExp" value="^javax\."/>
+            <property name="standardPackageRegExp" value="^java\."/>
+            <property name="sortImportsInGroupAlphabetically" value="true"/>
+            <property name="separateLineBetweenGroups" value="false"/>
+        </module>
+        <module name="MethodParamPad"/>
+        <module name="NoWhitespaceBefore">
+            <property name="tokens"
+                      value="COMMA, SEMI, POST_INC, POST_DEC, DOT, ELLIPSIS, METHOD_REF"/>
+            <property name="allowLineBreaks" value="true"/>
+        </module>
+        <module name="ParenPad"/>
+        <module name="OperatorWrap">
+            <property name="option" value="eol"/>
+            <property name="tokens"
+                      value="BAND, BOR, BSR, BXOR, DIV, EQUAL, GE, GT, LAND, LE, LITERAL_INSTANCEOF, LOR,
+                    LT, MINUS, MOD, NOT_EQUAL, PLUS, QUESTION, SL, SR, STAR, METHOD_REF "/>
+        </module>
+        <module name="AnnotationLocation">
+            <property name="id" value="AnnotationLocationMostCases"/>
+            <property name="tokens"
+                      value="CLASS_DEF, INTERFACE_DEF, ENUM_DEF, METHOD_DEF, CTOR_DEF"/>
+        </module>
+        <module name="AnnotationLocation">
+            <property name="id" value="AnnotationLocationVariables"/>
+            <property name="tokens" value="VARIABLE_DEF"/>
+            <property name="allowSamelineMultipleAnnotations" value="true"/>
+        </module>
+        <module name="NonEmptyAtclauseDescription"/>
+        <module name="JavadocTagContinuationIndentation"/>
+        <module name="SummaryJavadoc">
+            <property name="forbiddenSummaryFragments"
+                      value="^@return the *|^This method returns |^A [{]@code [a-zA-Z0-9]+[}]( is a )"/>
+        </module>
+        <module name="JavadocParagraph"/>
+        <module name="AtclauseOrder">
+            <property name="tagOrder" value="@param, @return, @throws, @deprecated"/>
+            <property name="target"
+                      value="CLASS_DEF, INTERFACE_DEF, ENUM_DEF, METHOD_DEF, CTOR_DEF, VARIABLE_DEF"/>
+        </module>
+        <module name="JavadocMethod">
+            <property name="scope" value="public"/>
+            <property name="allowedAnnotations" value="Override, Test"/>
+        </module>
+        <module name="MethodName">
+            <property name="format" value="^[a-z][a-z0-9][a-zA-Z0-9_]*$"/>
+            <message key="name.invalidPattern"
+                     value="Method name ''{0}'' must match pattern ''{1}''."/>
+        </module>
+        <module name="SingleLineJavadoc">
+            <property name="ignoreInlineTags" value="false"/>
+        </module>
+        <module name="EmptyCatchBlock">
+            <property name="exceptionVariableName" value="expected"/>
+        </module>
+        <module name="CommentsIndentation"/>
+        <module name="AvoidNestedBlocks"/>
+        <module name="AbstractClassName"/>
+        <module name="CyclomaticComplexity"/>
+        <module name="EmptyStatement"/>
+    </module>
+</module>

core-java/retrofit/introduction-to-retrofit/AuditApplication/mvnw

@@ -0,0 +1,310 @@
+#!/bin/sh
+# ----------------------------------------------------------------------------
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+# ----------------------------------------------------------------------------
+
+# ----------------------------------------------------------------------------
+# Maven Start Up Batch script
+#
+# Required ENV vars:
+# ------------------
+#   JAVA_HOME - location of a JDK home dir
+#
+# Optional ENV vars
+# -----------------
+#   M2_HOME - location of maven2's installed home dir
+#   MAVEN_OPTS - parameters passed to the Java VM when running Maven
+#     e.g. to debug Maven itself, use
+#       set MAVEN_OPTS=-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=8000
+#   MAVEN_SKIP_RC - flag to disable loading of mavenrc files
+# ----------------------------------------------------------------------------
+
+if [ -z "$MAVEN_SKIP_RC" ] ; then
+
+  if [ -f /etc/mavenrc ] ; then
+    . /etc/mavenrc
+  fi
+
+  if [ -f "$HOME/.mavenrc" ] ; then
+    . "$HOME/.mavenrc"
+  fi
+
+fi
+
+# OS specific support.  $var _must_ be set to either true or false.
+cygwin=false;
+darwin=false;
+mingw=false
+case "`uname`" in
+  CYGWIN*) cygwin=true ;;
+  MINGW*) mingw=true;;
+  Darwin*) darwin=true
+    # Use /usr/libexec/java_home if available, otherwise fall back to /Library/Java/Home
+    # See https://developer.apple.com/library/mac/qa/qa1170/_index.html
+    if [ -z "$JAVA_HOME" ]; then
+      if [ -x "/usr/libexec/java_home" ]; then
+        export JAVA_HOME="`/usr/libexec/java_home`"
+      else
+        export JAVA_HOME="/Library/Java/Home"
+      fi
+    fi
+    ;;
+esac
+
+if [ -z "$JAVA_HOME" ] ; then
+  if [ -r /etc/gentoo-release ] ; then
+    JAVA_HOME=`java-config --jre-home`
+  fi
+fi
+
+if [ -z "$M2_HOME" ] ; then
+  ## resolve links - $0 may be a link to maven's home
+  PRG="$0"
+
+  # need this for relative symlinks
+  while [ -h "$PRG" ] ; do
+    ls=`ls -ld "$PRG"`
+    link=`expr "$ls" : '.*-> \(.*\)$'`
+    if expr "$link" : '/.*' > /dev/null; then
+      PRG="$link"
+    else
+      PRG="`dirname "$PRG"`/$link"
+    fi
+  done
+
+  saveddir=`pwd`
+
+  M2_HOME=`dirname "$PRG"`/..
+
+  # make it fully qualified
+  M2_HOME=`cd "$M2_HOME" && pwd`
+
+  cd "$saveddir"
+  # echo Using m2 at $M2_HOME
+fi
+
+# For Cygwin, ensure paths are in UNIX format before anything is touched
+if $cygwin ; then
+  [ -n "$M2_HOME" ] &&
+    M2_HOME=`cygpath --unix "$M2_HOME"`
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME=`cygpath --unix "$JAVA_HOME"`
+  [ -n "$CLASSPATH" ] &&
+    CLASSPATH=`cygpath --path --unix "$CLASSPATH"`
+fi
+
+# For Mingw, ensure paths are in UNIX format before anything is touched
+if $mingw ; then
+  [ -n "$M2_HOME" ] &&
+    M2_HOME="`(cd "$M2_HOME"; pwd)`"
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME="`(cd "$JAVA_HOME"; pwd)`"
+fi
+
+if [ -z "$JAVA_HOME" ]; then
+  javaExecutable="`which javac`"
+  if [ -n "$javaExecutable" ] && ! [ "`expr \"$javaExecutable\" : '\([^ ]*\)'`" = "no" ]; then
+    # readlink(1) is not available as standard on Solaris 10.
+    readLink=`which readlink`
+    if [ ! `expr "$readLink" : '\([^ ]*\)'` = "no" ]; then
+      if $darwin ; then
+        javaHome="`dirname \"$javaExecutable\"`"
+        javaExecutable="`cd \"$javaHome\" && pwd -P`/javac"
+      else
+        javaExecutable="`readlink -f \"$javaExecutable\"`"
+      fi
+      javaHome="`dirname \"$javaExecutable\"`"
+      javaHome=`expr "$javaHome" : '\(.*\)/bin'`
+      JAVA_HOME="$javaHome"
+      export JAVA_HOME
+    fi
+  fi
+fi
+
+if [ -z "$JAVACMD" ] ; then
+  if [ -n "$JAVA_HOME"  ] ; then
+    if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
+      # IBM's JDK on AIX uses strange locations for the executables
+      JAVACMD="$JAVA_HOME/jre/sh/java"
+    else
+      JAVACMD="$JAVA_HOME/bin/java"
+    fi
+  else
+    JAVACMD="`which java`"
+  fi
+fi
+
+if [ ! -x "$JAVACMD" ] ; then
+  echo "Error: JAVA_HOME is not defined correctly." >&2
+  echo "  We cannot execute $JAVACMD" >&2
+  exit 1
+fi
+
+if [ -z "$JAVA_HOME" ] ; then
+  echo "Warning: JAVA_HOME environment variable is not set."
+fi
+
+CLASSWORLDS_LAUNCHER=org.codehaus.plexus.classworlds.launcher.Launcher
+
+# traverses directory structure from process work directory to filesystem root
+# first directory with .mvn subdirectory is considered project base directory
+find_maven_basedir() {
+
+  if [ -z "$1" ]
+  then
+    echo "Path not specified to find_maven_basedir"
+    return 1
+  fi
+
+  basedir="$1"
+  wdir="$1"
+  while [ "$wdir" != '/' ] ; do
+    if [ -d "$wdir"/.mvn ] ; then
+      basedir=$wdir
+      break
+    fi
+    # workaround for JBEAP-8937 (on Solaris 10/Sparc)
+    if [ -d "${wdir}" ]; then
+      wdir=`cd "$wdir/.."; pwd`
+    fi
+    # end of workaround
+  done
+  echo "${basedir}"
+}
+
+# concatenates all lines of a file
+concat_lines() {
+  if [ -f "$1" ]; then
+    echo "$(tr -s '\n' ' ' < "$1")"
+  fi
+}
+
+BASE_DIR=`find_maven_basedir "$(pwd)"`
+if [ -z "$BASE_DIR" ]; then
+  exit 1;
+fi
+
+##########################################################################################
+# Extension to allow automatically downloading the maven-wrapper.jar from Maven-central
+# This allows using the maven wrapper in projects that prohibit checking in binary data.
+##########################################################################################
+if [ -r "$BASE_DIR/.mvn/wrapper/maven-wrapper.jar" ]; then
+    if [ "$MVNW_VERBOSE" = true ]; then
+      echo "Found .mvn/wrapper/maven-wrapper.jar"
+    fi
+else
+    if [ "$MVNW_VERBOSE" = true ]; then
+      echo "Couldn't find .mvn/wrapper/maven-wrapper.jar, downloading it ..."
+    fi
+    if [ -n "$MVNW_REPOURL" ]; then
+      jarUrl="$MVNW_REPOURL/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar"
+    else
+      jarUrl="https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar"
+    fi
+    while IFS="=" read key value; do
+      case "$key" in (wrapperUrl) jarUrl="$value"; break ;;
+      esac
+    done < "$BASE_DIR/.mvn/wrapper/maven-wrapper.properties"
+    if [ "$MVNW_VERBOSE" = true ]; then
+      echo "Downloading from: $jarUrl"
+    fi
+    wrapperJarPath="$BASE_DIR/.mvn/wrapper/maven-wrapper.jar"
+    if $cygwin; then
+      wrapperJarPath=`cygpath --path --windows "$wrapperJarPath"`
+    fi
+
+    if command -v wget > /dev/null; then
+        if [ "$MVNW_VERBOSE" = true ]; then
+          echo "Found wget ... using wget"
+        fi
+        if [ -z "$MVNW_USERNAME" ] || [ -z "$MVNW_PASSWORD" ]; then
+            wget "$jarUrl" -O "$wrapperJarPath"
+        else
+            wget --http-user=$MVNW_USERNAME --http-password=$MVNW_PASSWORD "$jarUrl" -O "$wrapperJarPath"
+        fi
+    elif command -v curl > /dev/null; then
+        if [ "$MVNW_VERBOSE" = true ]; then
+          echo "Found curl ... using curl"
+        fi
+        if [ -z "$MVNW_USERNAME" ] || [ -z "$MVNW_PASSWORD" ]; then
+            curl -o "$wrapperJarPath" "$jarUrl" -f
+        else
+            curl --user $MVNW_USERNAME:$MVNW_PASSWORD -o "$wrapperJarPath" "$jarUrl" -f
+        fi
+
+    else
+        if [ "$MVNW_VERBOSE" = true ]; then
+          echo "Falling back to using Java to download"
+        fi
+        javaClass="$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.java"
+        # For Cygwin, switch paths to Windows format before running javac
+        if $cygwin; then
+          javaClass=`cygpath --path --windows "$javaClass"`
+        fi
+        if [ -e "$javaClass" ]; then
+            if [ ! -e "$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.class" ]; then
+                if [ "$MVNW_VERBOSE" = true ]; then
+                  echo " - Compiling MavenWrapperDownloader.java ..."
+                fi
+                # Compiling the Java class
+                ("$JAVA_HOME/bin/javac" "$javaClass")
+            fi
+            if [ -e "$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.class" ]; then
+                # Running the downloader
+                if [ "$MVNW_VERBOSE" = true ]; then
+                  echo " - Running MavenWrapperDownloader.java ..."
+                fi
+                ("$JAVA_HOME/bin/java" -cp .mvn/wrapper MavenWrapperDownloader "$MAVEN_PROJECTBASEDIR")
+            fi
+        fi
+    fi
+fi
+##########################################################################################
+# End of extension
+##########################################################################################
+
+export MAVEN_PROJECTBASEDIR=${MAVEN_BASEDIR:-"$BASE_DIR"}
+if [ "$MVNW_VERBOSE" = true ]; then
+  echo $MAVEN_PROJECTBASEDIR
+fi
+MAVEN_OPTS="$(concat_lines "$MAVEN_PROJECTBASEDIR/.mvn/jvm.config") $MAVEN_OPTS"
+
+# For Cygwin, switch paths to Windows format before running java
+if $cygwin; then
+  [ -n "$M2_HOME" ] &&
+    M2_HOME=`cygpath --path --windows "$M2_HOME"`
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME=`cygpath --path --windows "$JAVA_HOME"`
+  [ -n "$CLASSPATH" ] &&
+    CLASSPATH=`cygpath --path --windows "$CLASSPATH"`
+  [ -n "$MAVEN_PROJECTBASEDIR" ] &&
+    MAVEN_PROJECTBASEDIR=`cygpath --path --windows "$MAVEN_PROJECTBASEDIR"`
+fi
+
+# Provide a "standardized" way to retrieve the CLI args that will
+# work with both Windows and non-Windows executions.
+MAVEN_CMD_LINE_ARGS="$MAVEN_CONFIG $@"
+export MAVEN_CMD_LINE_ARGS
+
+WRAPPER_LAUNCHER=org.apache.maven.wrapper.MavenWrapperMain
+
+exec "$JAVACMD" \
+  $MAVEN_OPTS \
+  -classpath "$MAVEN_PROJECTBASEDIR/.mvn/wrapper/maven-wrapper.jar" \
+  "-Dmaven.home=${M2_HOME}" "-Dmaven.multiModuleProjectDirectory=${MAVEN_PROJECTBASEDIR}" \
+  ${WRAPPER_LAUNCHER} $MAVEN_CONFIG "$@"

core-java/retrofit/introduction-to-retrofit/AuditApplication/mvnw.cmd

@@ -0,0 +1,182 @@
+@REM ----------------------------------------------------------------------------
+@REM Licensed to the Apache Software Foundation (ASF) under one
+@REM or more contributor license agreements.  See the NOTICE file
+@REM distributed with this work for additional information
+@REM regarding copyright ownership.  The ASF licenses this file
+@REM to you under the Apache License, Version 2.0 (the
+@REM "License"); you may not use this file except in compliance
+@REM with the License.  You may obtain a copy of the License at
+@REM
+@REM    http://www.apache.org/licenses/LICENSE-2.0
+@REM
+@REM Unless required by applicable law or agreed to in writing,
+@REM software distributed under the License is distributed on an
+@REM "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+@REM KIND, either express or implied.  See the License for the
+@REM specific language governing permissions and limitations
+@REM under the License.
+@REM ----------------------------------------------------------------------------
+
+@REM ----------------------------------------------------------------------------
+@REM Maven Start Up Batch script
+@REM
+@REM Required ENV vars:
+@REM JAVA_HOME - location of a JDK home dir
+@REM
+@REM Optional ENV vars
+@REM M2_HOME - location of maven2's installed home dir
+@REM MAVEN_BATCH_ECHO - set to 'on' to enable the echoing of the batch commands
+@REM MAVEN_BATCH_PAUSE - set to 'on' to wait for a keystroke before ending
+@REM MAVEN_OPTS - parameters passed to the Java VM when running Maven
+@REM     e.g. to debug Maven itself, use
+@REM set MAVEN_OPTS=-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=8000
+@REM MAVEN_SKIP_RC - flag to disable loading of mavenrc files
+@REM ----------------------------------------------------------------------------
+
+@REM Begin all REM lines with '@' in case MAVEN_BATCH_ECHO is 'on'
+@echo off
+@REM set title of command window
+title %0
+@REM enable echoing by setting MAVEN_BATCH_ECHO to 'on'
+@if "%MAVEN_BATCH_ECHO%" == "on"  echo %MAVEN_BATCH_ECHO%
+
+@REM set %HOME% to equivalent of $HOME
+if "%HOME%" == "" (set "HOME=%HOMEDRIVE%%HOMEPATH%")
+
+@REM Execute a user defined script before this one
+if not "%MAVEN_SKIP_RC%" == "" goto skipRcPre
+@REM check for pre script, once with legacy .bat ending and once with .cmd ending
+if exist "%HOME%\mavenrc_pre.bat" call "%HOME%\mavenrc_pre.bat"
+if exist "%HOME%\mavenrc_pre.cmd" call "%HOME%\mavenrc_pre.cmd"
+:skipRcPre
+
+@setlocal
+
+set ERROR_CODE=0
+
+@REM To isolate internal variables from possible post scripts, we use another setlocal
+@setlocal
+
+@REM ==== START VALIDATION ====
+if not "%JAVA_HOME%" == "" goto OkJHome
+
+echo.
+echo Error: JAVA_HOME not found in your environment. >&2
+echo Please set the JAVA_HOME variable in your environment to match the >&2
+echo location of your Java installation. >&2
+echo.
+goto error
+
+:OkJHome
+if exist "%JAVA_HOME%\bin\java.exe" goto init
+
+echo.
+echo Error: JAVA_HOME is set to an invalid directory. >&2
+echo JAVA_HOME = "%JAVA_HOME%" >&2
+echo Please set the JAVA_HOME variable in your environment to match the >&2
+echo location of your Java installation. >&2
+echo.
+goto error
+
+@REM ==== END VALIDATION ====
+
+:init
+
+@REM Find the project base dir, i.e. the directory that contains the folder ".mvn".
+@REM Fallback to current working directory if not found.
+
+set MAVEN_PROJECTBASEDIR=%MAVEN_BASEDIR%
+IF NOT "%MAVEN_PROJECTBASEDIR%"=="" goto endDetectBaseDir
+
+set EXEC_DIR=%CD%
+set WDIR=%EXEC_DIR%
+:findBaseDir
+IF EXIST "%WDIR%"\.mvn goto baseDirFound
+cd ..
+IF "%WDIR%"=="%CD%" goto baseDirNotFound
+set WDIR=%CD%
+goto findBaseDir
+
+:baseDirFound
+set MAVEN_PROJECTBASEDIR=%WDIR%
+cd "%EXEC_DIR%"
+goto endDetectBaseDir
+
+:baseDirNotFound
+set MAVEN_PROJECTBASEDIR=%EXEC_DIR%
+cd "%EXEC_DIR%"
+
+:endDetectBaseDir
+
+IF NOT EXIST "%MAVEN_PROJECTBASEDIR%\.mvn\jvm.config" goto endReadAdditionalConfig
+
+@setlocal EnableExtensions EnableDelayedExpansion
+for /F "usebackq delims=" %%a in ("%MAVEN_PROJECTBASEDIR%\.mvn\jvm.config") do set JVM_CONFIG_MAVEN_PROPS=!JVM_CONFIG_MAVEN_PROPS! %%a
+@endlocal & set JVM_CONFIG_MAVEN_PROPS=%JVM_CONFIG_MAVEN_PROPS%
+
+:endReadAdditionalConfig
+
+SET MAVEN_JAVA_EXE="%JAVA_HOME%\bin\java.exe"
+set WRAPPER_JAR="%MAVEN_PROJECTBASEDIR%\.mvn\wrapper\maven-wrapper.jar"
+set WRAPPER_LAUNCHER=org.apache.maven.wrapper.MavenWrapperMain
+
+set DOWNLOAD_URL="https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar"
+
+FOR /F "tokens=1,2 delims==" %%A IN ("%MAVEN_PROJECTBASEDIR%\.mvn\wrapper\maven-wrapper.properties") DO (
+    IF "%%A"=="wrapperUrl" SET DOWNLOAD_URL=%%B
+)
+
+@REM Extension to allow automatically downloading the maven-wrapper.jar from Maven-central
+@REM This allows using the maven wrapper in projects that prohibit checking in binary data.
+if exist %WRAPPER_JAR% (
+    if "%MVNW_VERBOSE%" == "true" (
+        echo Found %WRAPPER_JAR%
+    )
+) else (
+    if not "%MVNW_REPOURL%" == "" (
+        SET DOWNLOAD_URL="%MVNW_REPOURL%/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar"
+    )
+    if "%MVNW_VERBOSE%" == "true" (
+        echo Couldn't find %WRAPPER_JAR%, downloading it ...
+        echo Downloading from: %DOWNLOAD_URL%
+    )
+
+    powershell -Command "&{"^
+		"$webclient = new-object System.Net.WebClient;"^
+		"if (-not ([string]::IsNullOrEmpty('%MVNW_USERNAME%') -and [string]::IsNullOrEmpty('%MVNW_PASSWORD%'))) {"^
+		"$webclient.Credentials = new-object System.Net.NetworkCredential('%MVNW_USERNAME%', '%MVNW_PASSWORD%');"^
+		"}"^
+		"[Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12; $webclient.DownloadFile('%DOWNLOAD_URL%', '%WRAPPER_JAR%')"^
+		"}"
+    if "%MVNW_VERBOSE%" == "true" (
+        echo Finished downloading %WRAPPER_JAR%
+    )
+)
+@REM End of extension
+
+@REM Provide a "standardized" way to retrieve the CLI args that will
+@REM work with both Windows and non-Windows executions.
+set MAVEN_CMD_LINE_ARGS=%*
+
+%MAVEN_JAVA_EXE% %JVM_CONFIG_MAVEN_PROPS% %MAVEN_OPTS% %MAVEN_DEBUG_OPTS% -classpath %WRAPPER_JAR% "-Dmaven.multiModuleProjectDirectory=%MAVEN_PROJECTBASEDIR%" %WRAPPER_LAUNCHER% %MAVEN_CONFIG% %*
+if ERRORLEVEL 1 goto error
+goto end
+
+:error
+set ERROR_CODE=1
+
+:end
+@endlocal & set ERROR_CODE=%ERROR_CODE%
+
+if not "%MAVEN_SKIP_RC%" == "" goto skipRcPost
+@REM check for post script, once with legacy .bat ending and once with .cmd ending
+if exist "%HOME%\mavenrc_post.bat" call "%HOME%\mavenrc_post.bat"
+if exist "%HOME%\mavenrc_post.cmd" call "%HOME%\mavenrc_post.cmd"
+:skipRcPost
+
+@REM pause the script if MAVEN_BATCH_PAUSE is set to 'on'
+if "%MAVEN_BATCH_PAUSE%" == "on" pause
+
+if "%MAVEN_TERMINATE_CMD%" == "on" exit %ERROR_CODE%
+
+exit /B %ERROR_CODE%

core-java/retrofit/introduction-to-retrofit/AuditApplication/pom.xml

@@ -0,0 +1,185 @@
+<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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+	<modelVersion>4.0.0</modelVersion>
+	<groupId>com.reflectoring</groupId>
+	<artifactId>audit-app</artifactId>
+	<version>0.0.1-SNAPSHOT</version>
+	<name>audit-app</name>
+	<properties>
+		<maven.compiler.source>11</maven.compiler.source>
+		<maven.compiler.target>11</maven.compiler.target>
+	</properties>
+
+	<parent>
+		<groupId>org.springframework.boot</groupId>
+		<artifactId>spring-boot-starter-parent</artifactId>
+		<version>2.3.2.RELEASE</version>
+		<relativePath />
+	</parent>
+
+	<dependencies>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-web</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-test</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>org.projectlombok</groupId>
+			<artifactId>lombok</artifactId>
+			<version>1.18.20</version>
+			<scope>provided</scope>
+		</dependency>
+		<dependency>
+			<groupId>org.projectlombok</groupId>
+			<artifactId>lombok-mapstruct-binding</artifactId>
+			<version>0.2.0</version>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-data-jpa</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>org.mapstruct</groupId>
+			<artifactId>mapstruct</artifactId>
+			<version>1.4.2.Final</version>
+		</dependency>
+		<dependency>
+			<groupId>org.hsqldb</groupId>
+			<artifactId>hsqldb</artifactId>
+			<version>2.4.0</version>
+			<scope>runtime</scope>
+		</dependency>
+		<dependency>
+			<groupId>commons-io</groupId>
+			<artifactId>commons-io</artifactId>
+			<version>2.11.0</version>
+		</dependency>
+		<dependency>
+			<groupId>com.squareup.retrofit2</groupId>
+			<artifactId>retrofit</artifactId>
+			<version>2.5.0</version>
+		</dependency>
+		<dependency>
+			<groupId>com.squareup.retrofit2</groupId>
+			<artifactId>converter-jackson</artifactId>
+			<version>2.5.0</version>
+		</dependency>
+		<dependency>
+			<groupId>com.squareup.okhttp3</groupId>
+			<artifactId>logging-interceptor</artifactId>
+			<version>3.4.0</version>
+		</dependency>
+		<dependency>
+			<groupId>com.squareup.retrofit2</groupId>
+			<artifactId>retrofit-mock</artifactId>
+			<version>2.5.0</version>
+			<scope>test</scope>
+		</dependency>
+
+
+
+		<dependency>
+			<groupId>org.junit.jupiter</groupId>
+			<artifactId>junit-jupiter-api</artifactId>
+			<version>5.7.0</version>
+			<scope>test</scope>
+		</dependency>
+		<dependency>
+			<groupId>org.junit.platform</groupId>
+			<artifactId>junit-platform-commons</artifactId>
+			<version>1.7.0</version>
+		</dependency>
+		<dependency>
+			<groupId>org.junit.jupiter</groupId>
+			<artifactId>junit-jupiter-engine</artifactId>
+			<version>5.7.0</version>
+			<scope>test</scope>
+		</dependency>
+
+	</dependencies>
+
+	<build>
+		<plugins>
+			<plugin>
+				<!-- Code style checks. Will fail the build if the code is not compliant. -->
+				<groupId>org.apache.maven.plugins</groupId>
+				<artifactId>maven-checkstyle-plugin</artifactId>
+				<version>3.1.1</version>
+				<configuration>
+					<configLocation>checkstyle.xml</configLocation>
+					<suppressionsLocation>checkstyle-suppressions.xml</suppressionsLocation>
+					<encoding>UTF-8</encoding>
+					<outputEncoding>UTF-8</outputEncoding>
+					<consoleOutput>true</consoleOutput>
+					<failsOnError>true</failsOnError>
+					<linkXRef>false</linkXRef>
+				</configuration>
+				<executions>
+					<execution>
+						<id>verify</id>
+						<phase>verify</phase>
+						<goals>
+							<goal>check</goal>
+						</goals>
+					</execution>
+				</executions>
+			</plugin>
+			<plugin>
+				<!-- Finds bugs in the code. Will fail the build if any are found. -->
+				<groupId>com.github.spotbugs</groupId>
+				<artifactId>spotbugs-maven-plugin</artifactId>
+				<version>4.5.3.0</version>
+				<dependencies>
+					<dependency>
+						<groupId>com.github.spotbugs</groupId>
+						<artifactId>spotbugs</artifactId>
+						<version>4.6.0</version>
+					</dependency>
+				</dependencies>
+				<configuration>
+					<encoding>UTF-8</encoding>
+					<outputEncoding>UTF-8</outputEncoding>
+					<includeTests>false</includeTests>
+					<excludeFilterFile>spotbugs-exclude.xml</excludeFilterFile>
+				</configuration>
+				<executions>
+					<execution>
+						<id>verify</id>
+						<phase>verify</phase>
+						<goals>
+							<goal>check</goal>
+						</goals>
+					</execution>
+				</executions>
+			</plugin>
+			<plugin>
+				<groupId>org.apache.maven.plugins</groupId>
+				<artifactId>maven-compiler-plugin</artifactId>
+				<version>3.8.0</version>
+				<configuration>
+					<source>11</source>
+					<target>11</target>
+					<annotationProcessorPaths>
+						<path>
+							<groupId>org.projectlombok</groupId>
+							<artifactId>lombok</artifactId>
+							<version>1.18.20</version>
+						</path>
+						<path>
+							<groupId>org.mapstruct</groupId>
+							<artifactId>mapstruct-processor</artifactId>
+							<version>1.4.2.Final</version>
+						</path>
+					</annotationProcessorPaths>
+				</configuration>
+			</plugin>
+		</plugins>
+	</build>
+
+
+
+</project>

core-java/retrofit/introduction-to-retrofit/AuditApplication/spotbugs-exclude.xml

@@ -0,0 +1,101 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<FindBugsFilter>
+
+    <Match>
+        <!-- This is required for Immutables (or any annotation processor generated classes causing havoc) -->
+        <Package name="~.*\.model\.?.*"/>
+
+        <Bug pattern="NP_METHOD_PARAMETER_TIGHTENS_ANNOTATION"/>
+    </Match>
+
+    <Match>
+        <!-- Sample model class. Need not be used -->
+        <Package name="~.*\.model\.?.*"/>
+
+        <Bug pattern="UUF_UNUSED_FIELD"/>
+    </Match>
+
+    <Match>
+        <!-- Sample model class. Need not be used -->
+        <Package name="~.*\.model\.?.*"/>
+
+        <Bug pattern="EI_EXPOSE_REP"/>
+    </Match>
+
+    <Match>
+        <!-- Sample model class. Need not be used -->
+        <Package name="~.*\.config\.?.*"/>
+
+        <Bug pattern="EI_EXPOSE_REP"/>
+    </Match>
+
+    <Match>
+        <!-- Sample model class. Need not be used -->
+        <Package name="~.*\.config\.?.*"/>
+
+        <Bug pattern="EI_EXPOSE_REP2"/>
+    </Match>
+
+    <Match>
+        <!-- Sample model class. Need not be used -->
+        <Package name="~.*\.service\.?.*"/>
+
+        <Bug pattern="EI_EXPOSE_REP"/>
+    </Match>
+
+    <Match>
+        <!-- Sample model class. Need not be used -->
+        <Package name="~.*\.service\.?.*"/>
+
+        <Bug pattern="EI_EXPOSE_REP2"/>
+    </Match>
+
+    <Match>
+        <!-- Sample model class. Need not be used -->
+        <Package name="~.*\.model\.?.*"/>
+
+        <Bug pattern="EI_EXPOSE_REP2"/>
+    </Match>
+
+    <Match>
+        <!-- Sample model class. Need not be used -->
+        <Package name="~.*\.exception\.?.*"/>
+
+        <Bug pattern="EI_EXPOSE_REP2"/>
+    </Match>
+
+    <Match>
+        <!-- Sample model class. Need not be used -->
+        <Package name="~.*\.exception\.?.*"/>
+
+        <Bug pattern="EI_EXPOSE_REP"/>
+    </Match>
+
+    <Match>
+        <!-- Sample model class. Need not be used -->
+        <Package name="~.*\.web\.?.*"/>
+
+        <Bug pattern="EI_EXPOSE_REP"/>
+    </Match>
+
+    <Match>
+        <!-- Sample model class. Need not be used -->
+        <Package name="~.*\.web\.?.*"/>
+
+        <Bug pattern="EI_EXPOSE_REP2"/>
+    </Match>
+
+    <Match>
+        <!-- Sample model class. Need not be read -->
+        <Package name="~.*\.model\.?.*"/>
+
+        <Bug pattern="URF_UNREAD_FIELD"/>
+    </Match>
+
+    <Match>
+        <Package name="~.*\.model\.?.*"/>
+
+        <Bug pattern="RV_RETURN_VALUE_IGNORED_NO_SIDE_EFFECT"/>
+    </Match>
+
+</FindBugsFilter>

core-java/retrofit/introduction-to-retrofit/AuditApplication/src/main/java/com/reflectoring/library/Application.java

@@ -0,0 +1,19 @@
+package com.reflectoring.library;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+public class Application {
+
+    private static Logger log = LoggerFactory.getLogger(Application.class);
+
+    public static void main(String[] args) {
+
+        SpringApplication.run(Application.class, args);
+
+    }
+
+}

core-java/retrofit/introduction-to-retrofit/AuditApplication/src/main/java/com/reflectoring/library/client/LibraryClient.java

@@ -0,0 +1,30 @@
+package com.reflectoring.library.client;
+
+import com.reflectoring.library.model.LibResponse;
+import com.reflectoring.library.model.mapstruct.BookDto;
+import retrofit2.Call;
+import retrofit2.http.*;
+
+import java.util.List;
+
+public interface LibraryClient {
+
+    /*@Headers({
+            "Accept: application/json",
+            "Cache-Control: max-age=640000"
+    })*/
+    @GET("/library/managed/books")
+    Call<List<BookDto>> getAllBooks(@Query("type") String type);
+
+    @GET("/library/managed/books/{requestId}")
+    Call<BookDto> getAllBooksWithHeaders(@Header("requestId") String requestId);
+
+    @POST("/library/managed/books")
+    Call<LibResponse> createNewBook(@Body BookDto book);
+
+    @PUT("/library/managed/books/{id}")
+    Call<LibResponse> updateBook(@Path("id") Long id, @Body BookDto book);
+
+    @DELETE("/library/managed/books/{id}")
+    Call<LibResponse> deleteBook(@Path("id") Long id);
+}

core-java/retrofit/introduction-to-retrofit/AuditApplication/src/main/java/com/reflectoring/library/config/ClientConfigProperties.java

@@ -0,0 +1,21 @@
+package com.reflectoring.library.config;
+
+import lombok.Getter;
+import lombok.Setter;
+import org.springframework.boot.context.properties.ConfigurationProperties;
+
+@ConfigurationProperties(prefix = "library")
+@Getter
+@Setter
+public class ClientConfigProperties {
+
+    private String endpoint;
+
+    private String username;
+
+    private String password;
+
+    private Integer connectionTimeout;
+
+    private Integer readWriteTimeout;
+}

core-java/retrofit/introduction-to-retrofit/AuditApplication/src/main/java/com/reflectoring/library/config/RestClientConfiguration.java

@@ -0,0 +1,45 @@
+package com.reflectoring.library.config;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.reflectoring.library.client.LibraryClient;
+import com.reflectoring.library.interceptor.BasicAuthInterceptor;
+import com.reflectoring.library.interceptor.CacheInterceptor;
+import okhttp3.Cache;
+import okhttp3.OkHttpClient;
+import okhttp3.logging.HttpLoggingInterceptor;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.context.properties.EnableConfigurationProperties;
+import org.springframework.context.ApplicationContext;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import retrofit2.Retrofit;
+import retrofit2.converter.jackson.JacksonConverterFactory;
+
+import java.io.File;
+import java.util.concurrent.TimeUnit;
+
+@Configuration
+@EnableConfigurationProperties(ClientConfigProperties.class)
+public class RestClientConfiguration {
+
+    @Bean
+    public LibraryClient libraryClient(ClientConfigProperties props) {
+        HttpLoggingInterceptor interceptor = new HttpLoggingInterceptor();
+        interceptor.setLevel(HttpLoggingInterceptor.Level.BODY);
+        Cache cache = new Cache(new File("cache"), 10 * 1024 * 1024);
+        OkHttpClient.Builder httpClientBuilder = new OkHttpClient.Builder()
+                .addInterceptor(new BasicAuthInterceptor(props.getUsername(), props.getPassword()))
+                .cache(cache)
+                .addNetworkInterceptor(new CacheInterceptor())
+                .addInterceptor(interceptor)
+                .connectTimeout(props.getConnectionTimeout(), TimeUnit.SECONDS)
+                .readTimeout(props.getReadWriteTimeout(), TimeUnit.SECONDS);
+
+        return new Retrofit.Builder().client(httpClientBuilder.build())
+                .baseUrl(props.getEndpoint())
+                .addConverterFactory(JacksonConverterFactory.create(new ObjectMapper()))
+                .build().create(LibraryClient.class);
+
+    }
+
+}

core-java/retrofit/introduction-to-retrofit/AuditApplication/src/main/java/com/reflectoring/library/interceptor/BasicAuthInterceptor.java

@@ -0,0 +1,26 @@
+package com.reflectoring.library.interceptor;
+
+import okhttp3.Credentials;
+import okhttp3.Interceptor;
+import okhttp3.Request;
+import okhttp3.Response;
+
+import java.io.IOException;
+
+public class BasicAuthInterceptor implements Interceptor {
+
+    private final String credentials;
+
+    public BasicAuthInterceptor(String user, String password) {
+        this.credentials = Credentials.basic(user, password);
+    }
+
+    @Override
+    public Response intercept(Chain chain) throws IOException {
+        Request request = chain.request();
+        Request authenticatedRequest = request.newBuilder()
+                .header("Authorization", credentials).build();
+        return chain.proceed(authenticatedRequest);
+    }
+
+}

core-java/retrofit/introduction-to-retrofit/AuditApplication/src/main/java/com/reflectoring/library/interceptor/CacheInterceptor.java

@@ -0,0 +1,25 @@
+package com.reflectoring.library.interceptor;
+
+import okhttp3.CacheControl;
+import okhttp3.Interceptor;
+import okhttp3.Response;
+
+import java.io.IOException;
+import java.util.concurrent.TimeUnit;
+
+public class CacheInterceptor implements Interceptor {
+    @Override
+    public Response intercept(Chain chain) throws IOException {
+        Response response = chain.proceed(chain.request());
+
+        CacheControl cacheControl = new CacheControl.Builder()
+                .maxAge(1, TimeUnit.MINUTES) // 1 minutes cache
+                .build();
+
+        return response.newBuilder()
+                .removeHeader("Pragma")
+                .removeHeader("Cache-Control")
+                .header("Cache-Control", cacheControl.toString())
+                .build();
+    }
+}

core-java/retrofit/introduction-to-retrofit/AuditApplication/src/main/java/com/reflectoring/library/mapper/AuditMapper.java

@@ -0,0 +1,99 @@
+package com.reflectoring.library.mapper;
+
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.reflectoring.library.model.LibResponse;
+import com.reflectoring.library.model.mapstruct.AuditDto;
+import com.reflectoring.library.model.mapstruct.BookDto;
+import com.reflectoring.library.util.Constants;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.http.HttpMethod;
+import org.springframework.stereotype.Component;
+
+import java.time.LocalDateTime;
+import java.util.List;
+import java.util.UUID;
+
+@Component
+public class AuditMapper {
+
+    private static final Logger LOG = LoggerFactory.getLogger(AuditMapper.class);
+
+    public AuditDto populateAuditLogForGet(List<BookDto> books) {
+        AuditDto log = null;
+        log = new AuditDto();
+        log.setId(UUID.randomUUID().toString());
+        log.setMethodType(HttpMethod.GET);
+        log.setRequest(null);
+        log.setResponse(String.valueOf(books.size()));
+        log.setSuccess(Constants.SUCCESS);
+        log.setTimestamp(LocalDateTime.now());
+        return log;
+
+    }
+
+    public AuditDto populateAuditLogForGetBook(BookDto book) {
+        AuditDto log = null;
+        log = new AuditDto();
+        log.setId(UUID.randomUUID().toString());
+        log.setMethodType(HttpMethod.GET);
+        log.setRequest(null);
+        log.setResponse(book.toString());
+        log.setSuccess(Constants.SUCCESS);
+        log.setTimestamp(LocalDateTime.now());
+        return log;
+
+    }
+
+    public AuditDto populateAuditLogForPostAndPut(BookDto book, LibResponse response, HttpMethod method) {
+        AuditDto log = null;
+        try {
+            log = new AuditDto();
+            log.setId(UUID.randomUUID().toString());
+            log.setMethodType(method);
+            log.setRequest(new ObjectMapper().writeValueAsString(book));
+            log.setResponse(new ObjectMapper().writeValueAsString(response));
+            log.setSuccess(Constants.SUCCESS);
+            log.setTimestamp(LocalDateTime.now());
+        } catch (JsonProcessingException ex) {
+            LOG.error("Error processing Object to json", ex);
+        }
+        return log;
+
+    }
+
+    public AuditDto populateAuditLogForDelete(Long id, LibResponse libResponse) {
+        AuditDto log = null;
+        try {
+            log = new AuditDto();
+            log.setId(UUID.randomUUID().toString());
+            log.setMethodType(HttpMethod.DELETE);
+            log.setRequest(String.valueOf(id));
+            log.setResponse(new ObjectMapper().writeValueAsString(libResponse));
+            log.setSuccess(Constants.SUCCESS);
+            log.setTimestamp(LocalDateTime.now());
+        } catch (JsonProcessingException ex) {
+            LOG.error("Error processing Object to json", ex);
+        }
+        return log;
+
+    }
+
+    public AuditDto populateAuditLogForException(String request, HttpMethod type, String errorResp) {
+        AuditDto log = null;
+        try {
+            log = new AuditDto();
+            log.setId(UUID.randomUUID().toString());
+            log.setMethodType(type);
+            log.setRequest(request);
+            log.setResponse(new ObjectMapper().writeValueAsString(errorResp));
+            log.setSuccess(Constants.ERROR);
+            log.setTimestamp(LocalDateTime.now());
+        } catch (JsonProcessingException ex) {
+            LOG.error("Error processing Object to json", ex);
+        }
+        return log;
+
+    }
+}

core-java/retrofit/introduction-to-retrofit/AuditApplication/src/main/java/com/reflectoring/library/mapper/LibraryMapper.java

@@ -0,0 +1,29 @@
+package com.reflectoring.library.mapper;
+
+import com.reflectoring.library.model.mapstruct.AuditDto;
+import com.reflectoring.library.model.mapstruct.AuthorDto;
+import com.reflectoring.library.model.mapstruct.BookDto;
+import com.reflectoring.library.model.persistence.AuditLog;
+import com.reflectoring.library.model.persistence.Author;
+import com.reflectoring.library.model.persistence.Book;
+import org.mapstruct.Mapper;
+import org.mapstruct.Mapping;
+
+import java.util.List;
+
+@Mapper(componentModel = "spring")
+public interface LibraryMapper {
+    BookDto bookToBookDto(Book book);
+
+    List<BookDto> bookToBookDto(List<Book> book);
+
+    AuthorDto authorToAuthorDto(Author author);
+
+    Book bookDtoToBook(BookDto bookDto);
+
+    Author authorDtoToAuthor(AuthorDto authorDto);
+
+    AuditLog auditDtoToAuditLog(AuditDto auditDto);
+
+    AuditDto auditLogToAuditDto(AuditLog auditLog);
+}

core-java/retrofit/introduction-to-retrofit/AuditApplication/src/main/java/com/reflectoring/library/model/LibResponse.java

@@ -0,0 +1,16 @@
+package com.reflectoring.library.model;
+
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.Setter;
+
+@Getter
+@Setter
+@AllArgsConstructor
+@NoArgsConstructor
+public class LibResponse {
+    private String responseCode;
+
+    private String responseMsg;
+}

core-java/retrofit/introduction-to-retrofit/AuditApplication/src/main/java/com/reflectoring/library/model/Status.java

@@ -0,0 +1,31 @@
+package com.reflectoring.library.model;
+
+public enum Status {
+    SUCCESS(200) {
+        @Override
+        public String toString() {
+            return "Success";
+        }
+    },
+    ERROR(500) {
+        @Override
+        public String toString() {
+            return "Error";
+        }
+    };
+
+    private int code;
+
+    Status(int code) {
+        this.code = code;
+    }
+
+    public static int fetchCode(String statusCode) {
+        for (Status s : Status.values()) {
+            if (s.name().equals(statusCode.toUpperCase())) {
+                return s.code;
+            }
+        }
+        return 0;
+    }
+}

core-java/retrofit/introduction-to-retrofit/AuditApplication/src/main/java/com/reflectoring/library/model/mapstruct/AuditDto.java

@@ -0,0 +1,39 @@
+package com.reflectoring.library.model.mapstruct;
+
+import com.fasterxml.jackson.annotation.JsonProperty;
+import lombok.AllArgsConstructor;
+import lombok.Builder;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.RequiredArgsConstructor;
+import lombok.Setter;
+import lombok.ToString;
+import org.springframework.http.HttpMethod;
+
+import java.time.LocalDateTime;
+
+@Getter
+@Setter
+@NoArgsConstructor
+@ToString
+public class AuditDto {
+
+    @JsonProperty("id")
+    private String id;
+
+    @JsonProperty("request")
+    private String request;
+
+    @JsonProperty("response")
+    private String response;
+
+    @JsonProperty("methodType")
+    private HttpMethod methodType;
+
+    @JsonProperty("success")
+    private String success;
+
+    @JsonProperty("timestamp")
+    private LocalDateTime timestamp;
+
+}

core-java/retrofit/introduction-to-retrofit/AuditApplication/src/main/java/com/reflectoring/library/model/mapstruct/AuthorDto.java

@@ -0,0 +1,30 @@
+package com.reflectoring.library.model.mapstruct;
+
+import com.fasterxml.jackson.annotation.JsonProperty;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.Setter;
+
+@Getter
+@Setter
+@NoArgsConstructor
+public class AuthorDto {
+
+    @JsonProperty("id")
+    private long id;
+
+    @JsonProperty("name")
+    private String name;
+
+    @JsonProperty("dob")
+    private String dob;
+
+    @Override
+    public String toString() {
+        return "AuthorDto{" +
+                "id=" + id +
+                ", name='" + name + '\'' +
+                ", dob='" + dob + '\'' +
+                '}';
+    }
+}

core-java/retrofit/introduction-to-retrofit/AuditApplication/src/main/java/com/reflectoring/library/model/mapstruct/BookDto.java

@@ -0,0 +1,43 @@
+package com.reflectoring.library.model.mapstruct;
+
+import com.fasterxml.jackson.annotation.JsonProperty;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.Setter;
+
+import java.util.Set;
+
+@Getter
+@Setter
+@NoArgsConstructor
+public class BookDto {
+    @JsonProperty("bookId")
+    private long id;
+
+    @JsonProperty("bookName")
+    private String name;
+
+    @JsonProperty("publisher")
+    private String publisher;
+
+    @JsonProperty("publicationYear")
+    private String publicationYear;
+
+    @JsonProperty("isCopyrighted")
+    private boolean copyrightIssued;
+
+    @JsonProperty("authors")
+    private Set<AuthorDto> authors;
+
+    @Override
+    public String toString() {
+        return "BookDto{" +
+                "id=" + id +
+                ", name='" + name + '\'' +
+                ", publisher='" + publisher + '\'' +
+                ", publicationYear='" + publicationYear + '\'' +
+                ", copyrightIssued=" + copyrightIssued +
+                ", authors=" + authors +
+                '}';
+    }
+}

core-java/retrofit/introduction-to-retrofit/AuditApplication/src/main/java/com/reflectoring/library/model/persistence/AuditLog.java

@@ -0,0 +1,34 @@
+package com.reflectoring.library.model.persistence;
+
+import lombok.Getter;
+import lombok.Setter;
+import org.springframework.http.HttpMethod;
+
+import javax.persistence.*;
+import java.time.LocalDateTime;
+
+@Entity
+@Table(name = "AUDIT_LOG")
+@Getter
+@Setter
+public class AuditLog {
+
+    @Id
+    private String id;
+
+    private String request;
+
+    private String response;
+
+    @Enumerated(EnumType.ORDINAL)
+    private HttpMethod methodType;
+
+    private String success;
+
+    @Column(name = "CURR_TIMESTAMP")
+    private LocalDateTime timestamp;
+
+    public AuditLog() {
+
+    }
+}

core-java/retrofit/introduction-to-retrofit/AuditApplication/src/main/java/com/reflectoring/library/model/persistence/Author.java

@@ -0,0 +1,69 @@
+package com.reflectoring.library.model.persistence;
+
+import com.fasterxml.jackson.annotation.JsonIgnore;
+import lombok.Builder;
+
+import javax.persistence.Entity;
+import javax.persistence.GeneratedValue;
+import javax.persistence.GenerationType;
+import javax.persistence.Id;
+import javax.persistence.ManyToMany;
+import java.io.Serializable;
+import java.util.List;
+import java.util.Set;
+
+@Entity
+public class Author implements Serializable {
+
+    @Id
+    @GeneratedValue(strategy = GenerationType.AUTO)
+    private long id;
+
+    private String name;
+
+    private String dob;
+
+    @ManyToMany(mappedBy = "authors")
+    private Set<Book> books;
+
+    public long getId() {
+        return id;
+    }
+
+    public void setId(long id) {
+        this.id = id;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public Set<Book> getBooks() {
+        return books;
+    }
+
+    public void setBooks(Set<Book> books) {
+        this.books = books;
+    }
+
+    public String getDob() {
+        return dob;
+    }
+
+    public void setDob(String dob) {
+        this.dob = dob;
+    }
+
+    @Override
+    public String toString() {
+        return "Author{" +
+                "id=" + id +
+                ", name='" + name + '\'' +
+                ", dob='" + dob + '\'' +
+                '}';
+    }
+}

core-java/retrofit/introduction-to-retrofit/AuditApplication/src/main/java/com/reflectoring/library/model/persistence/Book.java

@@ -0,0 +1,88 @@
+package com.reflectoring.library.model.persistence;
+
+import lombok.Builder;
+
+import javax.persistence.*;
+import java.io.Serializable;
+import java.util.Set;
+
+@Entity
+@Table(name = "BOOK")
+public class Book implements Serializable {
+    @Id
+    @GeneratedValue(strategy = GenerationType.AUTO)
+    private long id;
+
+    private String name;
+
+    private String publisher;
+
+    private String publicationYear;
+
+    private boolean copyrightIssued;
+
+    @ManyToMany(cascade = CascadeType.PERSIST, fetch = FetchType.LAZY)
+    @JoinTable(name = "author_book",
+            joinColumns = @JoinColumn(name = "book_id", referencedColumnName = "id"),
+            inverseJoinColumns = @JoinColumn(name = "author_id", referencedColumnName = "id"))
+    private Set<Author> authors;
+
+    public long getId() {
+        return id;
+    }
+
+    public void setId(long id) {
+        this.id = id;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public Set<Author> getAuthors() {
+        return authors;
+    }
+
+    public void setAuthors(Set<Author> authors) {
+        this.authors = authors;
+    }
+
+    public String getPublisher() {
+        return publisher;
+    }
+
+    public void setPublisher(String publisher) {
+        this.publisher = publisher;
+    }
+
+    public String getPublicationYear() {
+        return publicationYear;
+    }
+
+    public void setPublicationYear(String publicationYear) {
+        this.publicationYear = publicationYear;
+    }
+
+    public boolean isCopyrightIssued() {
+        return copyrightIssued;
+    }
+
+    public void setCopyrightIssued(boolean copyrightIssued) {
+        this.copyrightIssued = copyrightIssued;
+    }
+
+    @Override
+    public String toString() {
+        return "Book{" +
+                "id=" + id +
+                ", name='" + name + '\'' +
+                ", publisher='" + publisher + '\'' +
+                ", publicationYear='" + publicationYear + '\'' +
+                ", copyrightIssued=" + copyrightIssued +
+                '}';
+    }
+}

core-java/retrofit/introduction-to-retrofit/AuditApplication/src/main/java/com/reflectoring/library/repository/AuditRepository.java

@@ -0,0 +1,9 @@
+package com.reflectoring.library.repository;
+
+import com.reflectoring.library.model.persistence.AuditLog;
+import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.stereotype.Repository;
+
+@Repository
+public interface AuditRepository extends JpaRepository<AuditLog, String> {
+}

core-java/retrofit/introduction-to-retrofit/AuditApplication/src/main/java/com/reflectoring/library/repository/AuthorRepository.java

@@ -0,0 +1,9 @@
+package com.reflectoring.library.repository;
+
+import com.reflectoring.library.model.persistence.Author;
+import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.stereotype.Repository;
+
+@Repository
+public interface AuthorRepository extends JpaRepository<Author, Long> {
+}

core-java/retrofit/introduction-to-retrofit/AuditApplication/src/main/java/com/reflectoring/library/repository/BookRepository.java

@@ -0,0 +1,9 @@
+package com.reflectoring.library.repository;
+
+import com.reflectoring.library.model.persistence.Book;
+import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.stereotype.Repository;
+
+@Repository
+public interface BookRepository extends JpaRepository<Book, Long> {
+}

core-java/retrofit/introduction-to-retrofit/AuditApplication/src/main/java/com/reflectoring/library/service/LibraryAuditService.java

@@ -0,0 +1,218 @@
+package com.reflectoring.library.service;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.reflectoring.library.client.LibraryClient;
+import com.reflectoring.library.mapper.AuditMapper;
+import com.reflectoring.library.mapper.LibraryMapper;
+import com.reflectoring.library.model.LibResponse;
+import com.reflectoring.library.model.Status;
+import com.reflectoring.library.model.mapstruct.AuditDto;
+import com.reflectoring.library.model.mapstruct.BookDto;
+import com.reflectoring.library.model.persistence.AuditLog;
+import com.reflectoring.library.model.persistence.Book;
+import com.reflectoring.library.repository.AuditRepository;
+import com.reflectoring.library.util.Constants;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.http.HttpMethod;
+import org.springframework.stereotype.Service;
+import retrofit2.Call;
+import retrofit2.Callback;
+import retrofit2.Response;
+
+import java.util.*;
+
+@Service
+public class LibraryAuditService {
+
+    private static final Logger log = LoggerFactory.getLogger(LibraryAuditService.class);
+
+    private final LibraryMapper libraryMapper;
+
+    private final AuditMapper auditMapper;
+
+    private final AuditRepository auditRepository;
+
+    private final LibraryClient libraryClient;
+
+    public LibraryAuditService(LibraryMapper libraryMapper,
+                               AuditMapper auditMapper, AuditRepository auditRepository, LibraryClient libraryClient) {
+        this.libraryMapper = libraryMapper;
+        this.auditMapper = auditMapper;
+        this.auditRepository = auditRepository;
+        this.libraryClient = libraryClient;
+    }
+
+    /*public void getBooksAsync(String bookRequest) {
+        Call<BookDto> bookDtoCall = libraryClient.getAllBooksWithHeaders(bookRequest);
+        bookDtoCall.enqueue(new Callback<>() {
+            @Override
+            public void onResponse(Call<BookDto> call, Response<BookDto> response) {
+                if (response.isSuccessful()) {
+                    log.info("Success response : {}", response.body());
+                } else {
+                    log.info("Error response : {}", response.errorBody());
+                }
+            }
+
+            @Override
+            public void onFailure(Call<BookDto> call, Throwable throwable) {
+                log.info("Network error occured : {}", throwable.getLocalizedMessage());
+            }
+        });
+    }*/
+
+    public BookDto getBooks(String bookRequest) {
+        Response<BookDto> allBooksResponse = null;
+        BookDto books = null;
+        try {
+            AuditDto audit = null;
+            allBooksResponse = libraryClient.getAllBooksWithHeaders(bookRequest).execute();
+            if (allBooksResponse.isSuccessful()) {
+                books = allBooksResponse.body();
+                log.info("Get All Books : {}", books);
+                audit = auditMapper.populateAuditLogForGetBook(books);
+            } else {
+                log.error("Error calling library client: {}", allBooksResponse.errorBody());
+                if (Objects.nonNull(allBooksResponse.errorBody())) {
+                    audit = auditMapper.populateAuditLogForException(
+                            null, HttpMethod.GET, allBooksResponse.errorBody().string());
+                }
+
+            }
+
+            if (Objects.nonNull(audit)) {
+                AuditLog savedObj = auditRepository.save(libraryMapper.auditDtoToAuditLog(audit));
+                log.info("Saved into audit successfully: {}", savedObj);
+            }
+            return books;
+        } catch (Exception ex) {
+            log.error("Error handling retrofit call for getAllBooks", ex);
+            return books;
+        }
+
+    }
+
+    public List<BookDto> getAllBooks() {
+        List<BookDto> books = Collections.emptyList();
+        try {
+            AuditDto audit = null;
+            Call<List<BookDto>> callBookResponse = libraryClient.getAllBooks("all");
+            Response<List<BookDto>> allBooksResponse = callBookResponse.execute();
+            if (allBooksResponse.isSuccessful()) {
+                books = allBooksResponse.body();
+                log.info("Get All Books : {}", books);
+                audit = auditMapper.populateAuditLogForGet(books);
+            } else {
+                log.error("Error calling library client: {}", allBooksResponse.errorBody());
+                if (Objects.nonNull(allBooksResponse.errorBody())) {
+                    audit = auditMapper.populateAuditLogForException(
+                            null, HttpMethod.GET, allBooksResponse.errorBody().string());
+                }
+
+            }
+
+            if (Objects.nonNull(audit)) {
+                AuditLog savedObj = auditRepository.save(libraryMapper.auditDtoToAuditLog(audit));
+                log.info("Saved into audit successfully: {}", savedObj);
+            }
+            return books;
+        } catch (Exception ex) {
+            log.error("Error handling retrofit call for getAllBooks", ex);
+            return books;
+        }
+
+    }
+
+
+    public LibResponse createBook(BookDto bookDto) {
+        log.info("Book DTO from POST request : {}", bookDto);
+        LibResponse resp = null;
+        AuditDto audit = null;
+        try {
+            Call<LibResponse> callLibResponse = libraryClient.createNewBook(bookDto);
+            Response<LibResponse> libResponse = callLibResponse.execute();
+            if (libResponse.isSuccessful()) {
+                resp = libResponse.body();
+                audit = auditMapper.populateAuditLogForPostAndPut(bookDto, resp, HttpMethod.POST);
+            } else {
+                log.error("Error calling library client: {}", libResponse.errorBody());
+                if (Objects.nonNull(libResponse.errorBody())) {
+                    audit = auditMapper.populateAuditLogForException(
+                            new ObjectMapper().writeValueAsString(bookDto),
+                            HttpMethod.POST, libResponse.errorBody().string());
+                }
+            }
+            if (Objects.nonNull(audit)) {
+                AuditLog savedObj = auditRepository.save(libraryMapper.auditDtoToAuditLog(audit));
+                log.info("Saved into audit successfully: {}", savedObj);
+            }
+            return resp;
+        } catch (Exception ex) {
+            log.error("Error handling retrofit call for createNewBook", ex);
+            return new LibResponse(Constants.ERROR, "Failed");
+        }
+
+    }
+
+    public LibResponse updateBook(Long id, BookDto bookdto) {
+        log.info("Book DTO from PUT request : {}", bookdto);
+        LibResponse resp = null;
+        AuditDto audit = null;
+        try {
+            Call<LibResponse> callLibResponse = libraryClient.updateBook(id, bookdto);
+            Response<LibResponse> libResponse = callLibResponse.execute();
+            if (libResponse.isSuccessful()) {
+                resp = libResponse.body();
+                audit = auditMapper.populateAuditLogForPostAndPut(bookdto, resp, HttpMethod.PUT);
+            } else {
+                log.error("Error calling library client: {}", libResponse.errorBody());
+                if (Objects.nonNull(libResponse.errorBody())) {
+                    audit = auditMapper.populateAuditLogForException(
+                            new ObjectMapper().writeValueAsString(bookdto),
+                            HttpMethod.POST, libResponse.errorBody().string());
+                }
+            }
+        } catch (Exception ex) {
+            log.error("Error handling retrofit call for updateBook", ex);
+            resp = new LibResponse(Constants.ERROR, "Failed");
+        }
+
+        if (Objects.nonNull(audit)) {
+            AuditLog savedObj = auditRepository.save(libraryMapper.auditDtoToAuditLog(audit));
+            log.info("Saved into audit successfully: {}", savedObj);
+        }
+        return resp;
+    }
+
+    public LibResponse deleteBook(Long id) {
+        LibResponse resp = null;
+        AuditDto audit = null;
+        try {
+            Call<LibResponse> callLibResponse = libraryClient.deleteBook(id);
+            Response<LibResponse> libResponse = callLibResponse.execute();
+
+            if (libResponse.isSuccessful()) {
+                resp = libResponse.body();
+                audit = auditMapper.populateAuditLogForDelete(id, resp);
+            } else {
+                log.error("Error calling library client: {}", libResponse.errorBody());
+                if (Objects.nonNull(libResponse.errorBody())) {
+                    resp = new ObjectMapper().readValue(libResponse.errorBody().string(), LibResponse.class);
+                    audit = auditMapper.populateAuditLogForException(
+                            String.valueOf(id), HttpMethod.POST, libResponse.errorBody().string());
+                }
+            }
+        } catch (Exception ex) {
+            log.error("Error handling retrofit call for deleteBook", ex);
+            resp = new LibResponse(Constants.ERROR, "Failed");
+        }
+
+
+        if (Objects.nonNull(audit)) {
+            AuditLog savedObj = auditRepository.save(libraryMapper.auditDtoToAuditLog(audit));
+            log.info("Saved into audit successfully : {}", savedObj);
+        }
+        return resp;
+    }
+}

core-java/retrofit/introduction-to-retrofit/AuditApplication/src/main/java/com/reflectoring/library/util/Constants.java

@@ -0,0 +1,8 @@
+package com.reflectoring.library.util;
+
+public class Constants {
+
+    public static final String SUCCESS = "Success";
+
+    public static final String ERROR = "Error";
+}

core-java/retrofit/introduction-to-retrofit/AuditApplication/src/main/java/com/reflectoring/library/util/LocalDateTimeAttributeConverter.java

@@ -0,0 +1,22 @@
+package com.reflectoring.library.util;
+
+import org.springframework.stereotype.Component;
+
+import javax.persistence.AttributeConverter;
+import javax.persistence.Converter;
+import java.sql.Timestamp;
+import java.time.LocalDateTime;
+
+@Component
+@Converter(autoApply = true)
+public class LocalDateTimeAttributeConverter implements AttributeConverter<LocalDateTime, Timestamp> {
+    @Override
+    public Timestamp convertToDatabaseColumn(LocalDateTime localDateTime) {
+        return localDateTime == null ? null : Timestamp.valueOf(localDateTime);
+    }
+
+    @Override
+    public LocalDateTime convertToEntityAttribute(Timestamp timestamp) {
+        return timestamp == null ? null : timestamp.toLocalDateTime();
+    }
+}

core-java/retrofit/introduction-to-retrofit/AuditApplication/src/main/java/com/reflectoring/library/web/LibraryAuditController.java

@@ -0,0 +1,54 @@
+package com.reflectoring.library.web;
+
+import com.reflectoring.library.model.LibResponse;
+import com.reflectoring.library.model.Status;
+import com.reflectoring.library.model.mapstruct.BookDto;
+import com.reflectoring.library.service.LibraryAuditService;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.*;
+
+import java.util.List;
+import java.util.Map;
+
+@RestController
+@RequestMapping("library/managed/books")
+public class LibraryAuditController {
+
+    private static final Logger log = LoggerFactory.getLogger(LibraryAuditController.class);
+
+    private final LibraryAuditService libraryAuditService;
+
+    public LibraryAuditController(LibraryAuditService libraryAuditService) {
+        this.libraryAuditService = libraryAuditService;
+    }
+
+    @GetMapping
+    public ResponseEntity<List<BookDto>> getBooks() {
+        return ResponseEntity.ok().body(libraryAuditService.getAllBooks());
+    }
+
+    @GetMapping("/requestId")
+    public ResponseEntity<BookDto> getBooksWithHeaders(@RequestHeader String bookRequest) {
+        return ResponseEntity.ok().body(libraryAuditService.getBooks(bookRequest));
+    }
+
+    @PostMapping
+    public ResponseEntity<LibResponse> createBook(@RequestBody BookDto book) {
+        return ResponseEntity.ok().body(libraryAuditService.createBook(book));
+    }
+
+    @PutMapping(value = "/{id}", produces = "application/json")
+    public ResponseEntity<LibResponse> updateBook(@PathVariable Long id, @RequestBody BookDto book) {
+        return ResponseEntity.ok().body(libraryAuditService.updateBook(id, book));
+    }
+
+    @DeleteMapping(value = "{id}", produces = "application/json")
+    public ResponseEntity<LibResponse> deleteBook(@PathVariable Long id) {
+        LibResponse response = libraryAuditService.deleteBook(id);
+        log.info("Response received : {}", response);
+        log.info("Status from response : {}", Status.fetchCode(response.getResponseCode()));
+        return ResponseEntity.status(Status.fetchCode(response.getResponseCode())).body(response);
+    }
+}

core-java/retrofit/introduction-to-retrofit/AuditApplication/src/main/resources/application.yaml

@@ -0,0 +1,21 @@
+spring:
+  datasource:
+    driver-class-name: org.hsqldb.jdbc.JDBCDriver
+    url: jdbc:hsqldb:mem:auditdb;DB_CLOSE_DELAY=-1
+    username: sa
+    password:
+
+  jpa:
+    defer-datasource-initialization: true
+    hibernate:
+      ddl-auto: create
+
+server:
+  port: 8081
+
+library:
+  endpoint: http://localhost:8090
+  username: libuser
+  password: libpass
+  connectionTimeout: 30
+  readWriteTimeout: 30

core-java/retrofit/introduction-to-retrofit/AuditApplication/src/main/resources/schema.sql

@@ -0,0 +1,3 @@
+CREATE SCHEMA IF NOT EXISTS auditdb;
+DROP TABLE IF EXISTS AUDIT_LOG;
+CREATE TABLE IF NOT EXISTS AUDIT_LOG(ID VARCHAR(30), REQUEST VARCHAR(1000), RESPONSE VARCHAR(1000), METHOD_TYPE VARCHAR(10), SUCCESS VARCHAR(10), CURR_TIMESTAMP TIMESTAMP );

core-java/retrofit/introduction-to-retrofit/AuditApplication/src/test/java/com/reflectoring/library/service/LibraryAuditServiceTest.java

@@ -0,0 +1,150 @@
+package com.reflectoring.library.service;
+
+import com.fasterxml.jackson.core.type.TypeReference;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.reflectoring.library.client.LibraryClient;
+import com.reflectoring.library.mapper.AuditMapper;
+import com.reflectoring.library.mapper.LibraryMapper;
+import com.reflectoring.library.model.LibResponse;
+import com.reflectoring.library.model.Status;
+import com.reflectoring.library.model.mapstruct.BookDto;
+import com.reflectoring.library.repository.AuditRepository;
+import okhttp3.MediaType;
+import okhttp3.ResponseBody;
+import org.apache.commons.io.IOUtils;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.runner.RunWith;
+import org.mockito.Mock;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.test.context.junit4.SpringRunner;
+import retrofit2.Response;
+import retrofit2.mock.Calls;
+
+import java.io.IOException;
+import java.util.List;
+
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertTrue;
+import static org.junit.jupiter.api.Assertions.assertAll;
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.Mockito.doReturn;
+import static org.mockito.Mockito.when;
+
+@SpringBootTest
+@RunWith(SpringRunner.class)
+public class LibraryAuditServiceTest {
+
+    private static final Logger log = LoggerFactory.getLogger(LibraryAuditServiceTest.class);
+
+    @Autowired
+    private LibraryMapper libraryMapper;
+
+    @Autowired
+    private AuditMapper auditMapper;
+
+    @Mock
+    private LibraryClient libraryClient;
+
+    @Mock
+    private AuditRepository auditRepository;
+
+    private LibraryAuditService libraryAuditService;
+
+    @Before
+    public void setup() {
+        libraryAuditService = new LibraryAuditService(libraryMapper, auditMapper, auditRepository, libraryClient);
+    }
+
+
+    @Test
+    @DisplayName("Successful getAllBooks call")
+    public void getAllBooksTest() throws Exception {
+        String booksResponse = getBooksResponse("/response/getAllBooks.json");
+        List<BookDto> bookDtoList =
+                new ObjectMapper().readValue(booksResponse, new TypeReference<>() {
+                });
+        when(libraryClient.getAllBooks("all")).thenReturn(Calls.response(bookDtoList));
+        doReturn(null).when(auditRepository).save(any());
+        List<BookDto> allBooks = libraryAuditService.getAllBooks();
+        assertAll(
+                () -> assertNotNull(allBooks),
+                () -> assertTrue(allBooks.size()>0)
+        );
+
+    }
+
+    @Test
+    @DisplayName("Successful call to get a specific book")
+    public void getRequestBookTest() throws Exception {
+        String booksResponse = getBooksResponse("/response/getOneBook.json");
+        BookDto bookDto = new ObjectMapper().readValue(booksResponse, BookDto.class);
+        when(libraryClient.getAllBooksWithHeaders("1")).thenReturn(Calls.response(bookDto));
+        doReturn(null).when(auditRepository).save(any());
+        BookDto book = libraryAuditService.getBooks("1");
+        assertAll(
+                () -> assertNotNull(book),
+                () -> assertTrue(book.getId()==1)
+        );
+
+    }
+
+    @Test
+    @DisplayName("Successful call to create a book")
+    public void postBookRequestTest() throws Exception {
+        String booksResponse = getBooksResponse("/request/postBook.json");
+        BookDto bookDto = new ObjectMapper().readValue(booksResponse, BookDto.class);
+        LibResponse response = new LibResponse("Success", "Book created successfully");
+        when(libraryClient.createNewBook(bookDto)).thenReturn(Calls.response(response));
+        doReturn(null).when(auditRepository).save(any());
+        LibResponse libResponse = libraryAuditService.createBook(bookDto);
+        assertAll(
+                () -> assertNotNull(libResponse),
+                () -> assertTrue(libResponse.getResponseCode().equals("Success"))
+        );
+
+    }
+
+    @Test
+    @DisplayName("Successful call to update a book")
+    public void putBookRequestTest() throws Exception {
+        String booksResponse = getBooksResponse("/request/putBook.json");
+        BookDto bookDto = new ObjectMapper().readValue(booksResponse, BookDto.class);
+        LibResponse response = new LibResponse("Success", "Book updated successfully");
+        when(libraryClient.updateBook(Long.valueOf("1"), bookDto)).thenReturn(Calls.response(response));
+        doReturn(null).when(auditRepository).save(any());
+        LibResponse libResponse = libraryAuditService.updateBook(Long.valueOf("1"), bookDto);
+        assertAll(
+                () -> assertNotNull(libResponse),
+                () -> assertTrue(libResponse.getResponseCode().equals("Success"))
+        );
+
+    }
+
+    @Test
+    @DisplayName("Cannot delete a book")
+    public void deleteBookRequestTest() throws Exception {
+        LibResponse response = new LibResponse(Status.ERROR.toString(), "Could not delete book for id : 1000");
+        ResponseBody respBody = ResponseBody.create(MediaType.parse("application/json"),
+                new ObjectMapper().writeValueAsString(response));
+        Response<LibResponse> respLib = Response.error(500, respBody);
+        when(libraryClient.deleteBook(Long.valueOf("1000"))).thenReturn(Calls.response(respLib));
+        doReturn(null).when(auditRepository).save(any());
+        LibResponse libResponse = libraryAuditService.deleteBook(Long.valueOf("1000"));
+        assertAll(
+                () -> assertNotNull(libResponse),
+                () -> assertTrue(libResponse.getResponseCode().equals("Error"))
+        );
+
+    }
+
+
+    private String getBooksResponse(String path) throws IOException {
+        return IOUtils.toString(this.getClass().getResourceAsStream(path));
+    }
+
+}

core-java/retrofit/introduction-to-retrofit/AuditApplication/src/test/resources/request/postBook.json

@@ -0,0 +1,10 @@
+{
+  "bookName": "The Monk who sold his Ferrari",
+  "publisher": "c",
+  "publicationYear": "2009",
+  "isCopyrighted": true,
+  "authors": [{
+    "name": "Robin Sharma",
+    "dob" : "16/06/1964"
+  }]
+}

core-java/retrofit/introduction-to-retrofit/AuditApplication/src/test/resources/request/putBook.json

@@ -0,0 +1,5 @@
+{
+  "bookName": "The Monk who sold his Ferrari - 01",
+  "publisher": "The Monk who sold his Ferrari",
+  "publicationYear": "2010"
+}

core-java/retrofit/introduction-to-retrofit/AuditApplication/src/test/resources/response/getAllBooks.json

@@ -0,0 +1,15 @@
+[
+  {
+    "bookId": 1,
+    "bookName": "The Da Vinci Code",
+    "publisher": "Corgie Adult",
+    "publicationYear": "2009",
+    "isCopyrighted": true,
+    "authors": [{
+      "id": 2,
+      "name": "Dan Brown",
+      "dob" : "22/06/1964"
+    }]
+  }
+
+]

core-java/retrofit/introduction-to-retrofit/AuditApplication/src/test/resources/response/getOneBook.json

@@ -0,0 +1,14 @@
+
+  {
+    "bookId": 1,
+    "bookName": "The Da Vinci Code",
+    "publisher": "Corgie Adult",
+    "publicationYear": "2009",
+    "isCopyrighted": true,
+    "authors": [{
+      "id": 2,
+      "name": "Dan Brown",
+      "dob" : "22/06/1964"
+    }]
+  }
+

core-java/retrofit/introduction-to-retrofit/SimpleLibraryApplication/.gitignore

@@ -0,0 +1,2 @@
+# Project exclude paths
+/target/

core-java/retrofit/introduction-to-retrofit/SimpleLibraryApplication/.mvn/wrapper/MavenWrapperDownloader.java

@@ -0,0 +1,117 @@
+/*
+ * Copyright 2007-present the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+import java.net.*;
+import java.io.*;
+import java.nio.channels.*;
+import java.util.Properties;
+
+public class MavenWrapperDownloader {
+
+    private static final String WRAPPER_VERSION = "0.5.6";
+    /**
+     * Default URL to download the maven-wrapper.jar from, if no 'downloadUrl' is provided.
+     */
+    private static final String DEFAULT_DOWNLOAD_URL = "https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/"
+        + WRAPPER_VERSION + "/maven-wrapper-" + WRAPPER_VERSION + ".jar";
+
+    /**
+     * Path to the maven-wrapper.properties file, which might contain a downloadUrl property to
+     * use instead of the default one.
+     */
+    private static final String MAVEN_WRAPPER_PROPERTIES_PATH =
+            ".mvn/wrapper/maven-wrapper.properties";
+
+    /**
+     * Path where the maven-wrapper.jar will be saved to.
+     */
+    private static final String MAVEN_WRAPPER_JAR_PATH =
+            ".mvn/wrapper/maven-wrapper.jar";
+
+    /**
+     * Name of the property which should be used to override the default download url for the wrapper.
+     */
+    private static final String PROPERTY_NAME_WRAPPER_URL = "wrapperUrl";
+
+    public static void main(String args[]) {
+        System.out.println("- Downloader started");
+        File baseDirectory = new File(args[0]);
+        System.out.println("- Using base directory: " + baseDirectory.getAbsolutePath());
+
+        // If the maven-wrapper.properties exists, read it and check if it contains a custom
+        // wrapperUrl parameter.
+        File mavenWrapperPropertyFile = new File(baseDirectory, MAVEN_WRAPPER_PROPERTIES_PATH);
+        String url = DEFAULT_DOWNLOAD_URL;
+        if(mavenWrapperPropertyFile.exists()) {
+            FileInputStream mavenWrapperPropertyFileInputStream = null;
+            try {
+                mavenWrapperPropertyFileInputStream = new FileInputStream(mavenWrapperPropertyFile);
+                Properties mavenWrapperProperties = new Properties();
+                mavenWrapperProperties.load(mavenWrapperPropertyFileInputStream);
+                url = mavenWrapperProperties.getProperty(PROPERTY_NAME_WRAPPER_URL, url);
+            } catch (IOException e) {
+                System.out.println("- ERROR loading '" + MAVEN_WRAPPER_PROPERTIES_PATH + "'");
+            } finally {
+                try {
+                    if(mavenWrapperPropertyFileInputStream != null) {
+                        mavenWrapperPropertyFileInputStream.close();
+                    }
+                } catch (IOException e) {
+                    // Ignore ...
+                }
+            }
+        }
+        System.out.println("- Downloading from: " + url);
+
+        File outputFile = new File(baseDirectory.getAbsolutePath(), MAVEN_WRAPPER_JAR_PATH);
+        if(!outputFile.getParentFile().exists()) {
+            if(!outputFile.getParentFile().mkdirs()) {
+                System.out.println(
+                        "- ERROR creating output directory '" + outputFile.getParentFile().getAbsolutePath() + "'");
+            }
+        }
+        System.out.println("- Downloading to: " + outputFile.getAbsolutePath());
+        try {
+            downloadFileFromURL(url, outputFile);
+            System.out.println("Done");
+            System.exit(0);
+        } catch (Throwable e) {
+            System.out.println("- Error downloading");
+            e.printStackTrace();
+            System.exit(1);
+        }
+    }
+
+    private static void downloadFileFromURL(String urlString, File destination) throws Exception {
+        if (System.getenv("MVNW_USERNAME") != null && System.getenv("MVNW_PASSWORD") != null) {
+            String username = System.getenv("MVNW_USERNAME");
+            char[] password = System.getenv("MVNW_PASSWORD").toCharArray();
+            Authenticator.setDefault(new Authenticator() {
+                @Override
+                protected PasswordAuthentication getPasswordAuthentication() {
+                    return new PasswordAuthentication(username, password);
+                }
+            });
+        }
+        URL website = new URL(urlString);
+        ReadableByteChannel rbc;
+        rbc = Channels.newChannel(website.openStream());
+        FileOutputStream fos = new FileOutputStream(destination);
+        fos.getChannel().transferFrom(rbc, 0, Long.MAX_VALUE);
+        fos.close();
+        rbc.close();
+    }
+
+}

core-java/retrofit/introduction-to-retrofit/SimpleLibraryApplication/.mvn/wrapper/maven-wrapper.properties

@@ -0,0 +1,2 @@
+distributionUrl=https://repo.maven.apache.org/maven2/org/apache/maven/apache-maven/3.6.3/apache-maven-3.6.3-bin.zip
+wrapperUrl=https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar

core-java/retrofit/introduction-to-retrofit/SimpleLibraryApplication/README.md

@@ -0,0 +1,39 @@
+# A simple Spring Boot & Springfox library application
+This application manages a database of books and authors 
+
+## Details
+ * This application uses the default demo HSQLDB schema to maintain book and authors.
+ * It uses Spring Boot to create REST endpoints
+ * For the endpoint documentation it uses Swagger2
+ * It uses Maven and Java11 to build and run.
+
+## How to run
+ * Clone this project
+ * Use maven command: `mvn clean verify spring-boot:run`
+ * The application should run at `http://localhost:8090`
+ * The swagger documentation will be available at `http://localhost:8090/swagger-ui.html#/`
+ * Uses Basic auth for authentication.
+
+## Sample request JSON body
+# POST Sample
+````json
+{
+"bookName": "The Da Vinci Code",
+"publisher": "Corgie Adult",
+"publicationYear": "2009",
+"isCopyrighted": true,
+"authors": [{
+"name": "Dan Brown",
+"dob" : "22/06/1964"
+}]
+}
+````
+
+# PUT Sample
+````json
+{
+    "bookName": "The Da Vinci Code",
+    "publisher": "Corgie Adult - 01",
+    "publicationYear": "2010"
+}
+````

core-java/retrofit/introduction-to-retrofit/SimpleLibraryApplication/checkstyle-suppressions.xml

@@ -0,0 +1,7 @@
+<?xml version="1.0"?>
+<!DOCTYPE suppressions PUBLIC
+        "-//Checkstyle//DTD SuppressionFilter Configuration 1.2//EN"
+        "https://checkstyle.org/dtds/suppressions_1_2.dtd">
+<suppressions>
+    <suppress files="[/\\]target[/\\]generated-sources[/\\]" checks=".*" />
+</suppressions>

core-java/retrofit/introduction-to-retrofit/SimpleLibraryApplication/checkstyle.xml

@@ -0,0 +1,246 @@
+<?xml version="1.0"?>
+<!DOCTYPE module PUBLIC
+        "-//Checkstyle//DTD Checkstyle Configuration 1.3//EN"
+        "https://checkstyle.org/dtds/configuration_1_3.dtd">
+
+<module name="Checker">
+    <property name="charset" value="UTF-8"/>
+
+    <property name="severity" value="error"/>
+
+    <property name="fileExtensions" value="java, properties, xml"/>
+
+    <module name="BeforeExecutionExclusionFileFilter">
+        <property name="fileNamePattern" value="module\-info\.java$"/>
+    </module>
+
+    <module name="FileTabCharacter">
+        <property name="eachLine" value="true"/>
+    </module>
+
+    <module name="LineLength">
+        <property name="max" value="120"/>
+        <property name="ignorePattern" value="^package.*|^import.*|a href|href|http://|https://|ftp://"/>
+    </module>
+
+    <module name="TreeWalker">
+        <module name="OuterTypeFilename"/>
+        <module name="IllegalTokenText">
+            <property name="tokens" value="STRING_LITERAL, CHAR_LITERAL"/>
+            <property name="format"
+                      value="\\u00(09|0(a|A)|0(c|C)|0(d|D)|22|27|5(C|c))|\\(0(10|11|12|14|15|42|47)|134)"/>
+            <property name="message"
+                      value="Consider using special escape sequence instead of octal value or Unicode escaped value."/>
+        </module>
+        <module name="AvoidEscapedUnicodeCharacters">
+            <property name="allowEscapesForControlCharacters" value="true"/>
+            <property name="allowByTailComment" value="true"/>
+            <property name="allowNonPrintableEscapes" value="true"/>
+        </module>
+        <module name="OneTopLevelClass"/>
+        <module name="NoLineWrap"/>
+        <module name="EmptyBlock">
+            <property name="option" value="TEXT"/>
+            <property name="tokens"
+                      value="LITERAL_TRY, LITERAL_FINALLY, LITERAL_IF, LITERAL_ELSE, LITERAL_SWITCH"/>
+        </module>
+        <module name="LeftCurly"/>
+        <module name="RightCurly">
+            <property name="id" value="RightCurlySame"/>
+            <property name="tokens"
+                      value="LITERAL_TRY, LITERAL_CATCH, LITERAL_FINALLY, LITERAL_IF, LITERAL_ELSE,
+                    LITERAL_DO"/>
+        </module>
+        <module name="RightCurly">
+            <property name="id" value="RightCurlyAlone"/>
+            <property name="option" value="alone"/>
+            <property name="tokens"
+                      value="CLASS_DEF, METHOD_DEF, CTOR_DEF, LITERAL_FOR, LITERAL_WHILE, STATIC_INIT,
+                    INSTANCE_INIT"/>
+        </module>
+        <module name="WhitespaceAround">
+            <property name="allowEmptyConstructors" value="true"/>
+            <property name="allowEmptyLambdas" value="true"/>
+            <property name="allowEmptyMethods" value="true"/>
+            <property name="allowEmptyTypes" value="true"/>
+            <property name="allowEmptyLoops" value="true"/>
+            <message key="ws.notFollowed"
+                     value="WhitespaceAround: ''{0}'' is not followed by whitespace. Empty blocks may only be represented as '{}' when not part of a multi-block statement (4.1.3)"/>
+            <message key="ws.notPreceded"
+                     value="WhitespaceAround: ''{0}'' is not preceded with whitespace."/>
+        </module>
+        <module name="OneStatementPerLine"/>
+        <module name="MultipleVariableDeclarations"/>
+        <module name="ArrayTypeStyle"/>
+        <module name="MissingSwitchDefault"/>
+        <module name="FallThrough"/>
+        <module name="UpperEll"/>
+        <module name="ModifierOrder"/>
+        <module name="SeparatorWrap">
+            <property name="id" value="SeparatorWrapDot"/>
+            <property name="tokens" value="DOT"/>
+            <property name="option" value="nl"/>
+        </module>
+        <module name="SeparatorWrap">
+            <property name="id" value="SeparatorWrapComma"/>
+            <property name="tokens" value="COMMA"/>
+            <property name="option" value="EOL"/>
+        </module>
+        <module name="SeparatorWrap">
+            <!-- ELLIPSIS is EOL until https://github.com/google/styleguide/issues/258 -->
+            <property name="id" value="SeparatorWrapEllipsis"/>
+            <property name="tokens" value="ELLIPSIS"/>
+            <property name="option" value="EOL"/>
+        </module>
+        <module name="SeparatorWrap">
+            <!-- ARRAY_DECLARATOR is EOL until https://github.com/google/styleguide/issues/259 -->
+            <property name="id" value="SeparatorWrapArrayDeclarator"/>
+            <property name="tokens" value="ARRAY_DECLARATOR"/>
+            <property name="option" value="EOL"/>
+        </module>
+        <module name="SeparatorWrap">
+            <property name="id" value="SeparatorWrapMethodRef"/>
+            <property name="tokens" value="METHOD_REF"/>
+            <property name="option" value="nl"/>
+        </module>
+        <module name="PackageName">
+            <property name="format" value="^[a-z]+(\.[a-z][a-z0-9]*)*$"/>
+            <message key="name.invalidPattern"
+                     value="Package name ''{0}'' must match pattern ''{1}''."/>
+        </module>
+        <module name="TypeName">
+            <message key="name.invalidPattern"
+                     value="Type name ''{0}'' must match pattern ''{1}''."/>
+        </module>
+        <module name="MemberName">
+            <property name="format" value="^[a-z][a-z0-9][a-zA-Z0-9]*$"/>
+            <message key="name.invalidPattern"
+                     value="Member name ''{0}'' must match pattern ''{1}''."/>
+        </module>
+        <module name="ParameterName">
+            <property name="format" value="^[a-z]([a-z0-9][a-zA-Z0-9]*)?$"/>
+            <message key="name.invalidPattern"
+                     value="Parameter name ''{0}'' must match pattern ''{1}''."/>
+        </module>
+        <module name="ParameterNumber"/>
+        <module name="LambdaParameterName">
+            <property name="format" value="^[a-z]([a-z0-9][a-zA-Z0-9]*)?$"/>
+            <message key="name.invalidPattern"
+                     value="Lambda parameter name ''{0}'' must match pattern ''{1}''."/>
+        </module>
+        <module name="CatchParameterName">
+            <property name="format" value="^[a-z]([a-z0-9][a-zA-Z0-9]*)?$"/>
+            <message key="name.invalidPattern"
+                     value="Catch parameter name ''{0}'' must match pattern ''{1}''."/>
+        </module>
+        <module name="LocalVariableName">
+            <property name="tokens" value="VARIABLE_DEF"/>
+            <property name="format" value="^[a-z]([a-z0-9][a-zA-Z0-9]*)?$"/>
+            <message key="name.invalidPattern"
+                     value="Local variable name ''{0}'' must match pattern ''{1}''."/>
+        </module>
+        <module name="ClassTypeParameterName">
+            <property name="format" value="(^[A-Z][0-9]?)$|([A-Z][a-zA-Z0-9]*[T]$)"/>
+            <message key="name.invalidPattern"
+                     value="Class type name ''{0}'' must match pattern ''{1}''."/>
+        </module>
+        <module name="MethodTypeParameterName">
+            <property name="format" value="(^[A-Z][0-9]?)$|([A-Z][a-zA-Z0-9]*[T]$)"/>
+            <message key="name.invalidPattern"
+                     value="Method type name ''{0}'' must match pattern ''{1}''."/>
+        </module>
+        <module name="InterfaceTypeParameterName">
+            <property name="format" value="(^[A-Z][0-9]?)$|([A-Z][a-zA-Z0-9]*[T]$)"/>
+            <message key="name.invalidPattern"
+                     value="Interface type name ''{0}'' must match pattern ''{1}''."/>
+        </module>
+        <module name="NoFinalizer"/>
+        <module name="GenericWhitespace">
+            <message key="ws.followed"
+                     value="GenericWhitespace ''{0}'' is followed by whitespace."/>
+            <message key="ws.preceded"
+                     value="GenericWhitespace ''{0}'' is preceded with whitespace."/>
+            <message key="ws.illegalFollow"
+                     value="GenericWhitespace ''{0}'' should followed by whitespace."/>
+            <message key="ws.notPreceded"
+                     value="GenericWhitespace ''{0}'' is not preceded with whitespace."/>
+        </module>
+        <module name="Indentation">
+            <property name="basicOffset" value="4"/>
+            <property name="braceAdjustment" value="0"/>
+            <property name="caseIndent" value="4"/>
+            <property name="throwsIndent" value="8"/>
+            <property name="lineWrappingIndentation" value="8"/>
+            <property name="arrayInitIndent" value="4"/>
+        </module>
+        <module name="AbbreviationAsWordInName">
+            <property name="ignoreFinal" value="false"/>
+            <property name="allowedAbbreviationLength" value="1"/>
+        </module>
+        <module name="OverloadMethodsDeclarationOrder"/>
+        <module name="VariableDeclarationUsageDistance"/>
+        <module name="CustomImportOrder">
+            <property name="customImportOrderRules"
+                      value="THIRD_PARTY_PACKAGE###SPECIAL_IMPORTS###STANDARD_JAVA_PACKAGE###STATIC"/>
+            <property name="specialImportsRegExp" value="^javax\."/>
+            <property name="standardPackageRegExp" value="^java\."/>
+            <property name="sortImportsInGroupAlphabetically" value="true"/>
+            <property name="separateLineBetweenGroups" value="false"/>
+        </module>
+        <module name="MethodParamPad"/>
+        <module name="NoWhitespaceBefore">
+            <property name="tokens"
+                      value="COMMA, SEMI, POST_INC, POST_DEC, DOT, ELLIPSIS, METHOD_REF"/>
+            <property name="allowLineBreaks" value="true"/>
+        </module>
+        <module name="ParenPad"/>
+        <module name="OperatorWrap">
+            <property name="option" value="eol"/>
+            <property name="tokens"
+                      value="BAND, BOR, BSR, BXOR, DIV, EQUAL, GE, GT, LAND, LE, LITERAL_INSTANCEOF, LOR,
+                    LT, MINUS, MOD, NOT_EQUAL, PLUS, QUESTION, SL, SR, STAR, METHOD_REF "/>
+        </module>
+        <module name="AnnotationLocation">
+            <property name="id" value="AnnotationLocationMostCases"/>
+            <property name="tokens"
+                      value="CLASS_DEF, INTERFACE_DEF, ENUM_DEF, METHOD_DEF, CTOR_DEF"/>
+        </module>
+        <module name="AnnotationLocation">
+            <property name="id" value="AnnotationLocationVariables"/>
+            <property name="tokens" value="VARIABLE_DEF"/>
+            <property name="allowSamelineMultipleAnnotations" value="true"/>
+        </module>
+        <module name="NonEmptyAtclauseDescription"/>
+        <module name="JavadocTagContinuationIndentation"/>
+        <module name="SummaryJavadoc">
+            <property name="forbiddenSummaryFragments"
+                      value="^@return the *|^This method returns |^A [{]@code [a-zA-Z0-9]+[}]( is a )"/>
+        </module>
+        <module name="JavadocParagraph"/>
+        <module name="AtclauseOrder">
+            <property name="tagOrder" value="@param, @return, @throws, @deprecated"/>
+            <property name="target"
+                      value="CLASS_DEF, INTERFACE_DEF, ENUM_DEF, METHOD_DEF, CTOR_DEF, VARIABLE_DEF"/>
+        </module>
+        <module name="JavadocMethod">
+            <property name="scope" value="public"/>
+            <property name="allowedAnnotations" value="Override, Test"/>
+        </module>
+        <module name="MethodName">
+            <property name="format" value="^[a-z][a-z0-9][a-zA-Z0-9_]*$"/>
+            <message key="name.invalidPattern"
+                     value="Method name ''{0}'' must match pattern ''{1}''."/>
+        </module>
+        <module name="SingleLineJavadoc">
+            <property name="ignoreInlineTags" value="false"/>
+        </module>
+        <module name="EmptyCatchBlock">
+            <property name="exceptionVariableName" value="expected"/>
+        </module>
+        <module name="CommentsIndentation"/>
+        <module name="AvoidNestedBlocks"/>
+        <module name="AbstractClassName"/>
+        <module name="CyclomaticComplexity"/>
+        <module name="EmptyStatement"/>
+    </module>
+</module>

core-java/retrofit/introduction-to-retrofit/SimpleLibraryApplication/mvnw

@@ -0,0 +1,310 @@
+#!/bin/sh
+# ----------------------------------------------------------------------------
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+# ----------------------------------------------------------------------------
+
+# ----------------------------------------------------------------------------
+# Maven Start Up Batch script
+#
+# Required ENV vars:
+# ------------------
+#   JAVA_HOME - location of a JDK home dir
+#
+# Optional ENV vars
+# -----------------
+#   M2_HOME - location of maven2's installed home dir
+#   MAVEN_OPTS - parameters passed to the Java VM when running Maven
+#     e.g. to debug Maven itself, use
+#       set MAVEN_OPTS=-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=8000
+#   MAVEN_SKIP_RC - flag to disable loading of mavenrc files
+# ----------------------------------------------------------------------------
+
+if [ -z "$MAVEN_SKIP_RC" ] ; then
+
+  if [ -f /etc/mavenrc ] ; then
+    . /etc/mavenrc
+  fi
+
+  if [ -f "$HOME/.mavenrc" ] ; then
+    . "$HOME/.mavenrc"
+  fi
+
+fi
+
+# OS specific support.  $var _must_ be set to either true or false.
+cygwin=false;
+darwin=false;
+mingw=false
+case "`uname`" in
+  CYGWIN*) cygwin=true ;;
+  MINGW*) mingw=true;;
+  Darwin*) darwin=true
+    # Use /usr/libexec/java_home if available, otherwise fall back to /Library/Java/Home
+    # See https://developer.apple.com/library/mac/qa/qa1170/_index.html
+    if [ -z "$JAVA_HOME" ]; then
+      if [ -x "/usr/libexec/java_home" ]; then
+        export JAVA_HOME="`/usr/libexec/java_home`"
+      else
+        export JAVA_HOME="/Library/Java/Home"
+      fi
+    fi
+    ;;
+esac
+
+if [ -z "$JAVA_HOME" ] ; then
+  if [ -r /etc/gentoo-release ] ; then
+    JAVA_HOME=`java-config --jre-home`
+  fi
+fi
+
+if [ -z "$M2_HOME" ] ; then
+  ## resolve links - $0 may be a link to maven's home
+  PRG="$0"
+
+  # need this for relative symlinks
+  while [ -h "$PRG" ] ; do
+    ls=`ls -ld "$PRG"`
+    link=`expr "$ls" : '.*-> \(.*\)$'`
+    if expr "$link" : '/.*' > /dev/null; then
+      PRG="$link"
+    else
+      PRG="`dirname "$PRG"`/$link"
+    fi
+  done
+
+  saveddir=`pwd`
+
+  M2_HOME=`dirname "$PRG"`/..
+
+  # make it fully qualified
+  M2_HOME=`cd "$M2_HOME" && pwd`
+
+  cd "$saveddir"
+  # echo Using m2 at $M2_HOME
+fi
+
+# For Cygwin, ensure paths are in UNIX format before anything is touched
+if $cygwin ; then
+  [ -n "$M2_HOME" ] &&
+    M2_HOME=`cygpath --unix "$M2_HOME"`
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME=`cygpath --unix "$JAVA_HOME"`
+  [ -n "$CLASSPATH" ] &&
+    CLASSPATH=`cygpath --path --unix "$CLASSPATH"`
+fi
+
+# For Mingw, ensure paths are in UNIX format before anything is touched
+if $mingw ; then
+  [ -n "$M2_HOME" ] &&
+    M2_HOME="`(cd "$M2_HOME"; pwd)`"
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME="`(cd "$JAVA_HOME"; pwd)`"
+fi
+
+if [ -z "$JAVA_HOME" ]; then
+  javaExecutable="`which javac`"
+  if [ -n "$javaExecutable" ] && ! [ "`expr \"$javaExecutable\" : '\([^ ]*\)'`" = "no" ]; then
+    # readlink(1) is not available as standard on Solaris 10.
+    readLink=`which readlink`
+    if [ ! `expr "$readLink" : '\([^ ]*\)'` = "no" ]; then
+      if $darwin ; then
+        javaHome="`dirname \"$javaExecutable\"`"
+        javaExecutable="`cd \"$javaHome\" && pwd -P`/javac"
+      else
+        javaExecutable="`readlink -f \"$javaExecutable\"`"
+      fi
+      javaHome="`dirname \"$javaExecutable\"`"
+      javaHome=`expr "$javaHome" : '\(.*\)/bin'`
+      JAVA_HOME="$javaHome"
+      export JAVA_HOME
+    fi
+  fi
+fi
+
+if [ -z "$JAVACMD" ] ; then
+  if [ -n "$JAVA_HOME"  ] ; then
+    if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
+      # IBM's JDK on AIX uses strange locations for the executables
+      JAVACMD="$JAVA_HOME/jre/sh/java"
+    else
+      JAVACMD="$JAVA_HOME/bin/java"
+    fi
+  else
+    JAVACMD="`which java`"
+  fi
+fi
+
+if [ ! -x "$JAVACMD" ] ; then
+  echo "Error: JAVA_HOME is not defined correctly." >&2
+  echo "  We cannot execute $JAVACMD" >&2
+  exit 1
+fi
+
+if [ -z "$JAVA_HOME" ] ; then
+  echo "Warning: JAVA_HOME environment variable is not set."
+fi
+
+CLASSWORLDS_LAUNCHER=org.codehaus.plexus.classworlds.launcher.Launcher
+
+# traverses directory structure from process work directory to filesystem root
+# first directory with .mvn subdirectory is considered project base directory
+find_maven_basedir() {
+
+  if [ -z "$1" ]
+  then
+    echo "Path not specified to find_maven_basedir"
+    return 1
+  fi
+
+  basedir="$1"
+  wdir="$1"
+  while [ "$wdir" != '/' ] ; do
+    if [ -d "$wdir"/.mvn ] ; then
+      basedir=$wdir
+      break
+    fi
+    # workaround for JBEAP-8937 (on Solaris 10/Sparc)
+    if [ -d "${wdir}" ]; then
+      wdir=`cd "$wdir/.."; pwd`
+    fi
+    # end of workaround
+  done
+  echo "${basedir}"
+}
+
+# concatenates all lines of a file
+concat_lines() {
+  if [ -f "$1" ]; then
+    echo "$(tr -s '\n' ' ' < "$1")"
+  fi
+}
+
+BASE_DIR=`find_maven_basedir "$(pwd)"`
+if [ -z "$BASE_DIR" ]; then
+  exit 1;
+fi
+
+##########################################################################################
+# Extension to allow automatically downloading the maven-wrapper.jar from Maven-central
+# This allows using the maven wrapper in projects that prohibit checking in binary data.
+##########################################################################################
+if [ -r "$BASE_DIR/.mvn/wrapper/maven-wrapper.jar" ]; then
+    if [ "$MVNW_VERBOSE" = true ]; then
+      echo "Found .mvn/wrapper/maven-wrapper.jar"
+    fi
+else
+    if [ "$MVNW_VERBOSE" = true ]; then
+      echo "Couldn't find .mvn/wrapper/maven-wrapper.jar, downloading it ..."
+    fi
+    if [ -n "$MVNW_REPOURL" ]; then
+      jarUrl="$MVNW_REPOURL/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar"
+    else
+      jarUrl="https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar"
+    fi
+    while IFS="=" read key value; do
+      case "$key" in (wrapperUrl) jarUrl="$value"; break ;;
+      esac
+    done < "$BASE_DIR/.mvn/wrapper/maven-wrapper.properties"
+    if [ "$MVNW_VERBOSE" = true ]; then
+      echo "Downloading from: $jarUrl"
+    fi
+    wrapperJarPath="$BASE_DIR/.mvn/wrapper/maven-wrapper.jar"
+    if $cygwin; then
+      wrapperJarPath=`cygpath --path --windows "$wrapperJarPath"`
+    fi
+
+    if command -v wget > /dev/null; then
+        if [ "$MVNW_VERBOSE" = true ]; then
+          echo "Found wget ... using wget"
+        fi
+        if [ -z "$MVNW_USERNAME" ] || [ -z "$MVNW_PASSWORD" ]; then
+            wget "$jarUrl" -O "$wrapperJarPath"
+        else
+            wget --http-user=$MVNW_USERNAME --http-password=$MVNW_PASSWORD "$jarUrl" -O "$wrapperJarPath"
+        fi
+    elif command -v curl > /dev/null; then
+        if [ "$MVNW_VERBOSE" = true ]; then
+          echo "Found curl ... using curl"
+        fi
+        if [ -z "$MVNW_USERNAME" ] || [ -z "$MVNW_PASSWORD" ]; then
+            curl -o "$wrapperJarPath" "$jarUrl" -f
+        else
+            curl --user $MVNW_USERNAME:$MVNW_PASSWORD -o "$wrapperJarPath" "$jarUrl" -f
+        fi
+
+    else
+        if [ "$MVNW_VERBOSE" = true ]; then
+          echo "Falling back to using Java to download"
+        fi
+        javaClass="$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.java"
+        # For Cygwin, switch paths to Windows format before running javac
+        if $cygwin; then
+          javaClass=`cygpath --path --windows "$javaClass"`
+        fi
+        if [ -e "$javaClass" ]; then
+            if [ ! -e "$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.class" ]; then
+                if [ "$MVNW_VERBOSE" = true ]; then
+                  echo " - Compiling MavenWrapperDownloader.java ..."
+                fi
+                # Compiling the Java class
+                ("$JAVA_HOME/bin/javac" "$javaClass")
+            fi
+            if [ -e "$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.class" ]; then
+                # Running the downloader
+                if [ "$MVNW_VERBOSE" = true ]; then
+                  echo " - Running MavenWrapperDownloader.java ..."
+                fi
+                ("$JAVA_HOME/bin/java" -cp .mvn/wrapper MavenWrapperDownloader "$MAVEN_PROJECTBASEDIR")
+            fi
+        fi
+    fi
+fi
+##########################################################################################
+# End of extension
+##########################################################################################
+
+export MAVEN_PROJECTBASEDIR=${MAVEN_BASEDIR:-"$BASE_DIR"}
+if [ "$MVNW_VERBOSE" = true ]; then
+  echo $MAVEN_PROJECTBASEDIR
+fi
+MAVEN_OPTS="$(concat_lines "$MAVEN_PROJECTBASEDIR/.mvn/jvm.config") $MAVEN_OPTS"
+
+# For Cygwin, switch paths to Windows format before running java
+if $cygwin; then
+  [ -n "$M2_HOME" ] &&
+    M2_HOME=`cygpath --path --windows "$M2_HOME"`
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME=`cygpath --path --windows "$JAVA_HOME"`
+  [ -n "$CLASSPATH" ] &&
+    CLASSPATH=`cygpath --path --windows "$CLASSPATH"`
+  [ -n "$MAVEN_PROJECTBASEDIR" ] &&
+    MAVEN_PROJECTBASEDIR=`cygpath --path --windows "$MAVEN_PROJECTBASEDIR"`
+fi
+
+# Provide a "standardized" way to retrieve the CLI args that will
+# work with both Windows and non-Windows executions.
+MAVEN_CMD_LINE_ARGS="$MAVEN_CONFIG $@"
+export MAVEN_CMD_LINE_ARGS
+
+WRAPPER_LAUNCHER=org.apache.maven.wrapper.MavenWrapperMain
+
+exec "$JAVACMD" \
+  $MAVEN_OPTS \
+  -classpath "$MAVEN_PROJECTBASEDIR/.mvn/wrapper/maven-wrapper.jar" \
+  "-Dmaven.home=${M2_HOME}" "-Dmaven.multiModuleProjectDirectory=${MAVEN_PROJECTBASEDIR}" \
+  ${WRAPPER_LAUNCHER} $MAVEN_CONFIG "$@"

core-java/retrofit/introduction-to-retrofit/SimpleLibraryApplication/mvnw.cmd

@@ -0,0 +1,182 @@
+@REM ----------------------------------------------------------------------------
+@REM Licensed to the Apache Software Foundation (ASF) under one
+@REM or more contributor license agreements.  See the NOTICE file
+@REM distributed with this work for additional information
+@REM regarding copyright ownership.  The ASF licenses this file
+@REM to you under the Apache License, Version 2.0 (the
+@REM "License"); you may not use this file except in compliance
+@REM with the License.  You may obtain a copy of the License at
+@REM
+@REM    http://www.apache.org/licenses/LICENSE-2.0
+@REM
+@REM Unless required by applicable law or agreed to in writing,
+@REM software distributed under the License is distributed on an
+@REM "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+@REM KIND, either express or implied.  See the License for the
+@REM specific language governing permissions and limitations
+@REM under the License.
+@REM ----------------------------------------------------------------------------
+
+@REM ----------------------------------------------------------------------------
+@REM Maven Start Up Batch script
+@REM
+@REM Required ENV vars:
+@REM JAVA_HOME - location of a JDK home dir
+@REM
+@REM Optional ENV vars
+@REM M2_HOME - location of maven2's installed home dir
+@REM MAVEN_BATCH_ECHO - set to 'on' to enable the echoing of the batch commands
+@REM MAVEN_BATCH_PAUSE - set to 'on' to wait for a keystroke before ending
+@REM MAVEN_OPTS - parameters passed to the Java VM when running Maven
+@REM     e.g. to debug Maven itself, use
+@REM set MAVEN_OPTS=-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=8000
+@REM MAVEN_SKIP_RC - flag to disable loading of mavenrc files
+@REM ----------------------------------------------------------------------------
+
+@REM Begin all REM lines with '@' in case MAVEN_BATCH_ECHO is 'on'
+@echo off
+@REM set title of command window
+title %0
+@REM enable echoing by setting MAVEN_BATCH_ECHO to 'on'
+@if "%MAVEN_BATCH_ECHO%" == "on"  echo %MAVEN_BATCH_ECHO%
+
+@REM set %HOME% to equivalent of $HOME
+if "%HOME%" == "" (set "HOME=%HOMEDRIVE%%HOMEPATH%")
+
+@REM Execute a user defined script before this one
+if not "%MAVEN_SKIP_RC%" == "" goto skipRcPre
+@REM check for pre script, once with legacy .bat ending and once with .cmd ending
+if exist "%HOME%\mavenrc_pre.bat" call "%HOME%\mavenrc_pre.bat"
+if exist "%HOME%\mavenrc_pre.cmd" call "%HOME%\mavenrc_pre.cmd"
+:skipRcPre
+
+@setlocal
+
+set ERROR_CODE=0
+
+@REM To isolate internal variables from possible post scripts, we use another setlocal
+@setlocal
+
+@REM ==== START VALIDATION ====
+if not "%JAVA_HOME%" == "" goto OkJHome
+
+echo.
+echo Error: JAVA_HOME not found in your environment. >&2
+echo Please set the JAVA_HOME variable in your environment to match the >&2
+echo location of your Java installation. >&2
+echo.
+goto error
+
+:OkJHome
+if exist "%JAVA_HOME%\bin\java.exe" goto init
+
+echo.
+echo Error: JAVA_HOME is set to an invalid directory. >&2
+echo JAVA_HOME = "%JAVA_HOME%" >&2
+echo Please set the JAVA_HOME variable in your environment to match the >&2
+echo location of your Java installation. >&2
+echo.
+goto error
+
+@REM ==== END VALIDATION ====
+
+:init
+
+@REM Find the project base dir, i.e. the directory that contains the folder ".mvn".
+@REM Fallback to current working directory if not found.
+
+set MAVEN_PROJECTBASEDIR=%MAVEN_BASEDIR%
+IF NOT "%MAVEN_PROJECTBASEDIR%"=="" goto endDetectBaseDir
+
+set EXEC_DIR=%CD%
+set WDIR=%EXEC_DIR%
+:findBaseDir
+IF EXIST "%WDIR%"\.mvn goto baseDirFound
+cd ..
+IF "%WDIR%"=="%CD%" goto baseDirNotFound
+set WDIR=%CD%
+goto findBaseDir
+
+:baseDirFound
+set MAVEN_PROJECTBASEDIR=%WDIR%
+cd "%EXEC_DIR%"
+goto endDetectBaseDir
+
+:baseDirNotFound
+set MAVEN_PROJECTBASEDIR=%EXEC_DIR%
+cd "%EXEC_DIR%"
+
+:endDetectBaseDir
+
+IF NOT EXIST "%MAVEN_PROJECTBASEDIR%\.mvn\jvm.config" goto endReadAdditionalConfig
+
+@setlocal EnableExtensions EnableDelayedExpansion
+for /F "usebackq delims=" %%a in ("%MAVEN_PROJECTBASEDIR%\.mvn\jvm.config") do set JVM_CONFIG_MAVEN_PROPS=!JVM_CONFIG_MAVEN_PROPS! %%a
+@endlocal & set JVM_CONFIG_MAVEN_PROPS=%JVM_CONFIG_MAVEN_PROPS%
+
+:endReadAdditionalConfig
+
+SET MAVEN_JAVA_EXE="%JAVA_HOME%\bin\java.exe"
+set WRAPPER_JAR="%MAVEN_PROJECTBASEDIR%\.mvn\wrapper\maven-wrapper.jar"
+set WRAPPER_LAUNCHER=org.apache.maven.wrapper.MavenWrapperMain
+
+set DOWNLOAD_URL="https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar"
+
+FOR /F "tokens=1,2 delims==" %%A IN ("%MAVEN_PROJECTBASEDIR%\.mvn\wrapper\maven-wrapper.properties") DO (
+    IF "%%A"=="wrapperUrl" SET DOWNLOAD_URL=%%B
+)
+
+@REM Extension to allow automatically downloading the maven-wrapper.jar from Maven-central
+@REM This allows using the maven wrapper in projects that prohibit checking in binary data.
+if exist %WRAPPER_JAR% (
+    if "%MVNW_VERBOSE%" == "true" (
+        echo Found %WRAPPER_JAR%
+    )
+) else (
+    if not "%MVNW_REPOURL%" == "" (
+        SET DOWNLOAD_URL="%MVNW_REPOURL%/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar"
+    )
+    if "%MVNW_VERBOSE%" == "true" (
+        echo Couldn't find %WRAPPER_JAR%, downloading it ...
+        echo Downloading from: %DOWNLOAD_URL%
+    )
+
+    powershell -Command "&{"^
+		"$webclient = new-object System.Net.WebClient;"^
+		"if (-not ([string]::IsNullOrEmpty('%MVNW_USERNAME%') -and [string]::IsNullOrEmpty('%MVNW_PASSWORD%'))) {"^
+		"$webclient.Credentials = new-object System.Net.NetworkCredential('%MVNW_USERNAME%', '%MVNW_PASSWORD%');"^
+		"}"^
+		"[Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12; $webclient.DownloadFile('%DOWNLOAD_URL%', '%WRAPPER_JAR%')"^
+		"}"
+    if "%MVNW_VERBOSE%" == "true" (
+        echo Finished downloading %WRAPPER_JAR%
+    )
+)
+@REM End of extension
+
+@REM Provide a "standardized" way to retrieve the CLI args that will
+@REM work with both Windows and non-Windows executions.
+set MAVEN_CMD_LINE_ARGS=%*
+
+%MAVEN_JAVA_EXE% %JVM_CONFIG_MAVEN_PROPS% %MAVEN_OPTS% %MAVEN_DEBUG_OPTS% -classpath %WRAPPER_JAR% "-Dmaven.multiModuleProjectDirectory=%MAVEN_PROJECTBASEDIR%" %WRAPPER_LAUNCHER% %MAVEN_CONFIG% %*
+if ERRORLEVEL 1 goto error
+goto end
+
+:error
+set ERROR_CODE=1
+
+:end
+@endlocal & set ERROR_CODE=%ERROR_CODE%
+
+if not "%MAVEN_SKIP_RC%" == "" goto skipRcPost
+@REM check for post script, once with legacy .bat ending and once with .cmd ending
+if exist "%HOME%\mavenrc_post.bat" call "%HOME%\mavenrc_post.bat"
+if exist "%HOME%\mavenrc_post.cmd" call "%HOME%\mavenrc_post.cmd"
+:skipRcPost
+
+@REM pause the script if MAVEN_BATCH_PAUSE is set to 'on'
+if "%MAVEN_BATCH_PAUSE%" == "on" pause
+
+if "%MAVEN_TERMINATE_CMD%" == "on" exit %ERROR_CODE%
+
+exit /B %ERROR_CODE%

core-java/retrofit/introduction-to-retrofit/SimpleLibraryApplication/pom.xml

@@ -0,0 +1,172 @@
+<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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+	<modelVersion>4.0.0</modelVersion>
+	<groupId>com.reflectoring</groupId>
+	<artifactId>library-app</artifactId>
+	<version>0.0.1-SNAPSHOT</version>
+	<name>library-app</name>
+	<properties>
+		<maven.compiler.source>11</maven.compiler.source>
+		<maven.compiler.target>11</maven.compiler.target>
+	</properties>
+
+	<parent>
+		<groupId>org.springframework.boot</groupId>
+		<artifactId>spring-boot-starter-parent</artifactId>
+		<version>2.3.2.RELEASE</version>
+		<relativePath />
+	</parent>
+
+	<dependencies>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-web</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-test</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>org.projectlombok</groupId>
+			<artifactId>lombok</artifactId>
+			<version>1.18.20</version>
+			<scope>provided</scope>
+		</dependency>
+		<dependency>
+			<groupId>org.projectlombok</groupId>
+			<artifactId>lombok-mapstruct-binding</artifactId>
+			<version>0.2.0</version>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-data-jpa</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>org.mapstruct</groupId>
+			<artifactId>mapstruct</artifactId>
+			<version>1.4.2.Final</version>
+		</dependency>
+		<dependency>
+			<groupId>org.hsqldb</groupId>
+			<artifactId>hsqldb</artifactId>
+			<version>2.4.0</version>
+			<scope>runtime</scope>
+		</dependency>
+
+		<dependency>
+			<groupId>org.junit.jupiter</groupId>
+			<artifactId>junit-jupiter-api</artifactId>
+			<version>5.7.0</version>
+			<scope>test</scope>
+		</dependency>
+		<dependency>
+			<groupId>org.junit.platform</groupId>
+			<artifactId>junit-platform-commons</artifactId>
+			<version>1.7.0</version>
+		</dependency>
+		<dependency>
+			<groupId>org.junit.jupiter</groupId>
+			<artifactId>junit-jupiter-engine</artifactId>
+			<version>5.7.0</version>
+			<scope>test</scope>
+		</dependency>
+
+		<dependency>
+			<groupId>io.springfox</groupId>
+			<artifactId>springfox-swagger2</artifactId>
+			<version>2.9.2</version>
+		</dependency>
+		<dependency>
+			<groupId>io.springfox</groupId>
+			<artifactId>springfox-swagger-ui</artifactId>
+			<version>2.9.2</version>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-security</artifactId>
+		</dependency>
+
+	</dependencies>
+
+	<build>
+		<plugins>
+			<plugin>
+				<!-- Code style checks. Will fail the build if the code is not compliant. -->
+				<groupId>org.apache.maven.plugins</groupId>
+				<artifactId>maven-checkstyle-plugin</artifactId>
+				<version>3.1.1</version>
+				<configuration>
+					<configLocation>checkstyle.xml</configLocation>
+					<suppressionsLocation>checkstyle-suppressions.xml</suppressionsLocation>
+					<encoding>UTF-8</encoding>
+					<outputEncoding>UTF-8</outputEncoding>
+					<consoleOutput>true</consoleOutput>
+					<failsOnError>true</failsOnError>
+					<linkXRef>false</linkXRef>
+				</configuration>
+				<executions>
+					<execution>
+						<id>verify</id>
+						<phase>verify</phase>
+						<goals>
+							<goal>check</goal>
+						</goals>
+					</execution>
+				</executions>
+			</plugin>
+			<plugin>
+				<!-- Finds bugs in the code. Will fail the build if any are found. -->
+				<groupId>com.github.spotbugs</groupId>
+				<artifactId>spotbugs-maven-plugin</artifactId>
+				<version>4.5.3.0</version>
+				<dependencies>
+					<dependency>
+						<groupId>com.github.spotbugs</groupId>
+						<artifactId>spotbugs</artifactId>
+						<version>4.6.0</version>
+					</dependency>
+				</dependencies>
+				<configuration>
+					<encoding>UTF-8</encoding>
+					<outputEncoding>UTF-8</outputEncoding>
+					<includeTests>false</includeTests>
+					<excludeFilterFile>spotbugs-exclude.xml</excludeFilterFile>
+				</configuration>
+				<executions>
+					<execution>
+						<id>verify</id>
+						<phase>verify</phase>
+						<goals>
+							<goal>check</goal>
+						</goals>
+					</execution>
+				</executions>
+			</plugin>
+			<plugin>
+				<groupId>org.apache.maven.plugins</groupId>
+				<artifactId>maven-compiler-plugin</artifactId>
+				<version>3.8.0</version>
+				<configuration>
+					<source>11</source>
+					<target>11</target>
+					<annotationProcessorPaths>
+						<path>
+							<groupId>org.projectlombok</groupId>
+							<artifactId>lombok</artifactId>
+							<version>1.18.20</version>
+						</path>
+						<path>
+							<groupId>org.mapstruct</groupId>
+							<artifactId>mapstruct-processor</artifactId>
+							<version>1.4.2.Final</version>
+						</path>
+					</annotationProcessorPaths>
+				</configuration>
+			</plugin>
+		</plugins>
+	</build>
+
+
+
+</project>

core-java/retrofit/introduction-to-retrofit/SimpleLibraryApplication/spotbugs-exclude.xml

@@ -0,0 +1,87 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<FindBugsFilter>
+
+    <Match>
+        <!-- This is required for Immutables (or any annotation processor generated classes causing havoc) -->
+        <Package name="~.*\.model\.?.*"/>
+
+        <Bug pattern="NP_METHOD_PARAMETER_TIGHTENS_ANNOTATION"/>
+    </Match>
+
+    <Match>
+        <!-- Sample model class. Need not be used -->
+        <Package name="~.*\.model\.?.*"/>
+
+        <Bug pattern="UUF_UNUSED_FIELD"/>
+    </Match>
+
+    <Match>
+        <!-- Sample model class. Need not be used -->
+        <Package name="~.*\.model\.?.*"/>
+
+        <Bug pattern="EI_EXPOSE_REP"/>
+    </Match>
+
+    <Match>
+        <!-- Sample model class. Need not be used -->
+        <Package name="~.*\.config\.?.*"/>
+
+        <Bug pattern="EI_EXPOSE_REP"/>
+    </Match>
+
+    <Match>
+        <!-- Sample model class. Need not be used -->
+        <Package name="~.*\.config\.?.*"/>
+
+        <Bug pattern="EI_EXPOSE_REP2"/>
+    </Match>
+
+    <Match>
+        <!-- Sample model class. Need not be used -->
+        <Package name="~.*\.model\.?.*"/>
+
+        <Bug pattern="EI_EXPOSE_REP2"/>
+    </Match>
+
+    <Match>
+        <!-- Sample model class. Need not be used -->
+        <Package name="~.*\.exception\.?.*"/>
+
+        <Bug pattern="EI_EXPOSE_REP2"/>
+    </Match>
+
+    <Match>
+        <!-- Sample model class. Need not be used -->
+        <Package name="~.*\.exception\.?.*"/>
+
+        <Bug pattern="EI_EXPOSE_REP"/>
+    </Match>
+
+    <Match>
+        <!-- Sample model class. Need not be used -->
+        <Package name="~.*\.web\.?.*"/>
+
+        <Bug pattern="EI_EXPOSE_REP"/>
+    </Match>
+
+    <Match>
+        <!-- Sample model class. Need not be used -->
+        <Package name="~.*\.web\.?.*"/>
+
+        <Bug pattern="EI_EXPOSE_REP2"/>
+    </Match>
+
+    <Match>
+        <!-- Sample model class. Need not be read -->
+        <Package name="~.*\.model\.?.*"/>
+
+        <Bug pattern="URF_UNREAD_FIELD"/>
+    </Match>
+
+    <Match>
+        <Package name="~.*\.model\.?.*"/>
+
+        <Bug pattern="RV_RETURN_VALUE_IGNORED_NO_SIDE_EFFECT"/>
+    </Match>
+
+</FindBugsFilter>

core-java/retrofit/introduction-to-retrofit/SimpleLibraryApplication/src/main/java/com/reflectoring/library/Application.java

@@ -0,0 +1,19 @@
+package com.reflectoring.library;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+public class Application {
+
+    private static Logger log = LoggerFactory.getLogger(Application.class);
+
+    public static void main(String[] args) {
+
+        SpringApplication.run(Application.class, args);
+
+    }
+
+}

core-java/retrofit/introduction-to-retrofit/SimpleLibraryApplication/src/main/java/com/reflectoring/library/config/BasicAuthConfigProperties.java

@@ -0,0 +1,16 @@
+package com.reflectoring.library.config;
+
+import lombok.Getter;
+import lombok.Setter;
+import org.springframework.boot.context.properties.ConfigurationProperties;
+
+@ConfigurationProperties(prefix = "auth")
+@Getter
+@Setter
+public class BasicAuthConfigProperties {
+    private String username;
+
+    private String password;
+
+}
+

core-java/retrofit/introduction-to-retrofit/SimpleLibraryApplication/src/main/java/com/reflectoring/library/config/SecurityConfiguration.java

@@ -0,0 +1,65 @@
+package com.reflectoring.library.config;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.reflectoring.library.exception.AuthenticationErrorHandler;
+import org.springframework.boot.context.properties.EnableConfigurationProperties;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.security.config.annotation.authentication.builders.AuthenticationManagerBuilder;
+import org.springframework.security.config.annotation.web.builders.HttpSecurity;
+import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
+import org.springframework.security.config.annotation.web.configuration.WebSecurityConfigurerAdapter;
+import org.springframework.security.config.http.SessionCreationPolicy;
+import org.springframework.security.crypto.factory.PasswordEncoderFactories;
+import org.springframework.security.web.AuthenticationEntryPoint;
+import org.springframework.security.web.authentication.www.BasicAuthenticationFilter;
+
+@Configuration
+@EnableWebSecurity
+@EnableConfigurationProperties(BasicAuthConfigProperties.class)
+public class SecurityConfiguration  extends WebSecurityConfigurerAdapter {
+    private static final String URI_PATTERN = "/library/managed/**";
+
+    private final BasicAuthConfigProperties basicAuth;
+
+    public SecurityConfiguration(BasicAuthConfigProperties basicAuth) {
+        this.basicAuth = basicAuth;
+    }
+
+    @Override
+    protected void configure(HttpSecurity http) throws Exception {
+        http
+                .sessionManagement()
+                .sessionCreationPolicy(SessionCreationPolicy.STATELESS).and()
+                .authorizeRequests()
+                .antMatchers(URI_PATTERN).permitAll()
+                .antMatchers("/v2/api-docs/**").permitAll()
+                .antMatchers("/swagger-ui/**").permitAll()
+                .antMatchers("/swagger-ui.html").permitAll().and()
+                .addFilter(new BasicAuthenticationFilter(authenticationManager(),
+                        authenticationErrorHandler()))
+                .formLogin().disable()
+                .csrf().disable()
+                .exceptionHandling()
+                .authenticationEntryPoint(authenticationErrorHandler());
+    }
+
+    @Override
+    protected void configure(AuthenticationManagerBuilder auth) throws Exception {
+        auth
+                .inMemoryAuthentication()
+                .withUser(basicAuth.getUsername())
+                .password(PasswordEncoderFactories
+                        .createDelegatingPasswordEncoder()
+                        .encode(basicAuth.getPassword()))
+                .roles("USER");
+    }
+
+    @Bean
+    public AuthenticationEntryPoint authenticationErrorHandler() {
+        AuthenticationErrorHandler authErrorHandler =
+                new AuthenticationErrorHandler(new ObjectMapper());
+        authErrorHandler.setRealmName("Library Authentication");
+        return authErrorHandler;
+    }
+}

core-java/retrofit/introduction-to-retrofit/SimpleLibraryApplication/src/main/java/com/reflectoring/library/config/SwaggerConfig.java

@@ -0,0 +1,47 @@
+package com.reflectoring.library.config;
+
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import springfox.documentation.builders.PathSelectors;
+import springfox.documentation.builders.RequestHandlerSelectors;
+import springfox.documentation.service.AuthorizationScope;
+import springfox.documentation.service.BasicAuth;
+import springfox.documentation.service.SecurityReference;
+import springfox.documentation.service.SecurityScheme;
+import springfox.documentation.spi.DocumentationType;
+import springfox.documentation.spi.service.contexts.SecurityContext;
+import springfox.documentation.spring.web.plugins.Docket;
+import springfox.documentation.swagger2.annotations.EnableSwagger2;
+
+import java.util.ArrayList;
+
+@Configuration
+@EnableSwagger2
+public class SwaggerConfig {
+
+    @Bean
+    public Docket api() {
+
+        SecurityReference securityReference = SecurityReference.builder()
+                .reference("basicAuth")
+                .scopes(new AuthorizationScope[0])
+                .build();
+
+        ArrayList<SecurityReference> reference = new ArrayList<>(1);
+        reference.add(securityReference);
+
+        ArrayList<SecurityContext> securityContexts = new ArrayList<>(1);
+        securityContexts.add(SecurityContext.builder().securityReferences(reference).build());
+
+        ArrayList<SecurityScheme> auth = new ArrayList<>(1);
+        auth.add(new BasicAuth("basicAuth"));
+
+        return new Docket(DocumentationType.SWAGGER_2)
+                .securitySchemes(auth)
+                .securityContexts(securityContexts)
+                .select()
+                .paths(PathSelectors.ant("/library/managed/books/**"))
+                .apis(RequestHandlerSelectors.basePackage("com.reflectoring.library"))
+                .build();
+    }
+}

core-java/retrofit/introduction-to-retrofit/SimpleLibraryApplication/src/main/java/com/reflectoring/library/exception/AuthenticationErrorHandler.java

@@ -0,0 +1,30 @@
+package com.reflectoring.library.exception;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.reflectoring.library.model.Response;
+import com.reflectoring.library.model.Status;
+import org.springframework.security.core.AuthenticationException;
+import org.springframework.security.web.authentication.www.BasicAuthenticationEntryPoint;
+
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+import java.io.IOException;
+
+public class AuthenticationErrorHandler extends BasicAuthenticationEntryPoint {
+
+    private final ObjectMapper objectMapper;
+
+    public AuthenticationErrorHandler(ObjectMapper objectMapper) {
+        this.objectMapper = objectMapper;
+    }
+
+    @Override
+    public void commence(HttpServletRequest request,
+                         HttpServletResponse response,
+                         AuthenticationException ex) throws IOException {
+        response.setContentType("application/json");
+        response.setStatus(HttpServletResponse.SC_UNAUTHORIZED);
+        response.getOutputStream().println(objectMapper.writeValueAsString(
+                new Response(Status.ERROR.toString(), "Unauthorised")));
+    }
+}

core-java/retrofit/introduction-to-retrofit/SimpleLibraryApplication/src/main/java/com/reflectoring/library/mapper/LibraryMapper.java

@@ -0,0 +1,23 @@
+package com.reflectoring.library.mapper;
+
+import com.reflectoring.library.model.mapstruct.AuthorDto;
+import com.reflectoring.library.model.mapstruct.BookDto;
+import com.reflectoring.library.model.persistence.Author;
+import com.reflectoring.library.model.persistence.Book;
+import org.mapstruct.Mapper;
+import org.mapstruct.Mapping;
+
+import java.util.List;
+
+@Mapper(componentModel = "spring")
+public interface LibraryMapper {
+    BookDto bookToBookDto(Book book);
+
+    List<BookDto> bookToBookDto(List<Book> book);
+
+    AuthorDto authorToAuthorDto(Author author);
+
+    Book bookDtoToBook(BookDto bookDto);
+
+    Author authorDtoToAuthor(AuthorDto authorDto);
+}