JAVA-18142 New JHipster-6 module for JDK 11 (#13489)

* JAVA-18142 New JHipster-6 module for JDK 11 * JAVA-18142 Add jhipster-6 to jdk9-and-above * JAVA-18142 Re-enabled enforcer plugin * JAVA-18142 Fixed enforcer setup, upgraded spring boot * JAVA-18142 Try commiting package-lock.json * JAVA-18142 Removed package-lock.json * JAVA-18142 Added logs direectory to Git * JAVA-18142 Tried node npm version and legacy-peer-devs config * JAVA-18142 Added v for node.version * JAVA-18142 Corrected a config argument typo * JAVA-18142 Removed pre-jdk9 profiles * JAVA-18142 Verify Node/NPM upgrades are needed * JAVA-18142 Refactored remaining jhipster-5 references to jhipster-6 * JAVA-18142 Fixed more to jhipster6 namespace
2023-04-10 19:37:34 +03:00 · 2023-04-10 19:37:34 +03:00 · 42dff48c7d
parent 23c1abe3f2
commit 42dff48c7d
404 changed files with 29273 additions and 0 deletions
--- a/jhipster-6/README.md
+++ b/jhipster-6/README.md
@ -0,0 +1,3 @@
+## JHipster 6
+
+This module contains articles about JHipster 5. This is an aggregator module, articles are in the relevant submodules.
--- a/jhipster-6/bookstore-monolith/.editorconfig
+++ b/jhipster-6/bookstore-monolith/.editorconfig
@ -0,0 +1,24 @@
+# EditorConfig helps developers define and maintain consistent
+# coding styles between different editors and IDEs
+# editorconfig.org
+
+root = true
+
+[*]
+
+# Change these settings to your own preference
+indent_style = space
+indent_size = 4
+
+# We recommend you to keep these unchanged
+end_of_line = lf
+charset = utf-8
+trim_trailing_whitespace = true
+insert_final_newline = true
+
+[*.md]
+trim_trailing_whitespace = false
+
+[package.json]
+indent_style = space
+indent_size = 2
--- a/jhipster-6/bookstore-monolith/.gitattributes
+++ b/jhipster-6/bookstore-monolith/.gitattributes
@ -0,0 +1,148 @@
+# This file is inspired by https://github.com/alexkaratarakis/gitattributes
+#
+# Auto detect text files and perform LF normalization
+# http://davidlaing.com/2012/09/19/customise-your-gitattributes-to-become-a-git-ninja/
+* text=auto
+
+# The above will handle all files NOT found below
+# These files are text and should be normalized (Convert crlf => lf)
+
+*.bat           text eol=crlf
+*.coffee        text
+*.css           text
+*.cql           text
+*.df            text
+*.ejs           text
+*.html          text
+*.java          text
+*.js            text
+*.json          text
+*.less          text
+*.properties    text
+*.sass          text
+*.scss          text
+*.sh            text eol=lf
+*.sql           text
+*.txt           text
+*.ts            text
+*.xml           text
+*.yaml          text
+*.yml           text
+
+# Documents
+*.doc           diff=astextplain
+*.DOC           diff=astextplain
+*.docx          diff=astextplain
+*.DOCX          diff=astextplain
+*.dot           diff=astextplain
+*.DOT           diff=astextplain
+*.pdf           diff=astextplain
+*.PDF           diff=astextplain
+*.rtf           diff=astextplain
+*.RTF           diff=astextplain
+*.markdown      text
+*.md            text
+*.adoc          text
+*.textile       text
+*.mustache      text
+*.csv           text
+*.tab           text
+*.tsv           text
+*.txt           text
+AUTHORS         text
+CHANGELOG       text
+CHANGES         text
+CONTRIBUTING    text
+COPYING         text
+copyright       text
+*COPYRIGHT*     text
+INSTALL         text
+license         text
+LICENSE         text
+NEWS            text
+readme          text
+*README*        text
+TODO            text
+
+# Graphics
+*.png           binary
+*.jpg           binary
+*.jpeg          binary
+*.gif           binary
+*.tif           binary
+*.tiff          binary
+*.ico           binary
+# SVG treated as an asset (binary) by default. If you want to treat it as text,
+# comment-out the following line and uncomment the line after.
+*.svg           binary
+#*.svg          text
+*.eps           binary
+
+# These files are binary and should be left untouched
+# (binary is a macro for -text -diff)
+*.class         binary
+*.jar           binary
+*.war           binary
+
+## LINTERS
+.csslintrc      text
+.eslintrc       text
+.jscsrc         text
+.jshintrc       text
+.jshintignore   text
+.stylelintrc    text
+
+## CONFIGS
+*.conf          text
+*.config        text
+.editorconfig   text
+.gitattributes  text
+.gitconfig      text
+.gitignore      text
+.htaccess       text
+*.npmignore     text
+
+## HEROKU
+Procfile        text
+.slugignore     text
+
+## AUDIO
+*.kar           binary
+*.m4a           binary
+*.mid           binary
+*.midi          binary
+*.mp3           binary
+*.ogg           binary
+*.ra            binary
+
+## VIDEO
+*.3gpp          binary
+*.3gp           binary
+*.as            binary
+*.asf           binary
+*.asx           binary
+*.fla           binary
+*.flv           binary
+*.m4v           binary
+*.mng           binary
+*.mov           binary
+*.mp4           binary
+*.mpeg          binary
+*.mpg           binary
+*.swc           binary
+*.swf           binary
+*.webm          binary
+
+## ARCHIVES
+*.7z            binary
+*.gz            binary
+*.rar           binary
+*.tar           binary
+*.zip           binary
+
+## FONTS
+*.ttf           binary
+*.eot           binary
+*.otf           binary
+*.woff          binary
+*.woff2         binary
--- a/jhipster-6/bookstore-monolith/.gitignore
+++ b/jhipster-6/bookstore-monolith/.gitignore
@ -0,0 +1,146 @@
+######################
+# Project Specific
+######################
+/src/main/webapp/content/css/main.css
+/target/www/**
+/src/test/javascript/coverage/
+
+######################
+# Node
+######################
+/node/
+node_tmp/
+node_modules/
+npm-debug.log.*
+/.awcache/*
+/.cache-loader/*
+package-lock.json
+
+######################
+# SASS
+######################
+.sass-cache/
+
+######################
+# Eclipse
+######################
+*.pydevproject
+.project
+.metadata
+tmp/
+tmp/**/*
+*.tmp
+*.bak
+*.swp
+*~.nib
+local.properties
+.classpath
+.settings/
+.loadpath
+.factorypath
+/src/main/resources/rebel.xml
+
+# External tool builders
+.externalToolBuilders/**
+
+# Locally stored "Eclipse launch configurations"
+*.launch
+
+# CDT-specific
+.cproject
+
+# PDT-specific
+.buildpath
+
+######################
+# Intellij
+######################
+.idea/
+*.iml
+*.iws
+*.ipr
+*.ids
+*.orig
+classes/
+out/
+
+######################
+# Visual Studio Code
+######################
+.vscode/
+
+######################
+# Maven
+######################
+/log/
+/target/
+
+######################
+# Gradle
+######################
+.gradle/
+/build/
+
+######################
+# Package Files
+######################
+*.jar
+*.war
+*.ear
+*.db
+
+######################
+# Windows
+######################
+# Windows image file caches
+Thumbs.db
+
+# Folder config file
+Desktop.ini
+
+######################
+# Mac OSX
+######################
+.DS_Store
+.svn
+
+# Thumbnails
+._*
+
+# Files that might appear on external disk
+.Spotlight-V100
+.Trashes
+
+######################
+# Directories
+######################
+/bin/
+/deploy/
+
+######################
+# Logs
+######################
+*.log*
+
+######################
+# Others
+######################
+*.class
+*.*~
+*~
+.merge_file*
+
+######################
+# Gradle Wrapper
+######################
+!gradle/wrapper/gradle-wrapper.jar
+
+######################
+# Maven Wrapper
+######################
+!.mvn/wrapper/maven-wrapper.jar
+
+######################
+# ESLint
+######################
+.eslintcache
--- a/jhipster-6/bookstore-monolith/.huskyrc
+++ b/jhipster-6/bookstore-monolith/.huskyrc
@ -0,0 +1,5 @@
+{
+  "hooks": {
+     "pre-commit": "lint-staged"
+  }
+}
--- a/jhipster-6/bookstore-monolith/.jhipster/Book.json
+++ b/jhipster-6/bookstore-monolith/.jhipster/Book.json
@ -0,0 +1,54 @@
+{
+    "fluentMethods": true,
+    "clientRootFolder": "",
+    "relationships": [],
+    "fields": [
+        {
+            "fieldName": "title",
+            "fieldType": "String",
+            "fieldValidateRules": [
+                "required"
+            ]
+        },
+        {
+            "fieldName": "author",
+            "fieldType": "String",
+            "fieldValidateRules": [
+                "required"
+            ]
+        },
+        {
+            "fieldName": "published",
+            "fieldType": "LocalDate",
+            "fieldValidateRules": [
+                "required"
+            ]
+        },
+        {
+            "fieldName": "quantity",
+            "fieldType": "Integer",
+            "fieldValidateRules": [
+                "required",
+                "min"
+            ],
+            "fieldValidateRulesMin": 0
+        },
+        {
+            "fieldName": "price",
+            "fieldType": "Double",
+            "fieldValidateRules": [
+                "required",
+                "min"
+            ],
+            "fieldValidateRulesMin": 0
+        }
+    ],
+    "changelogDate": "20190319124041",
+    "dto": "mapstruct",
+    "searchEngine": false,
+    "service": "serviceImpl",
+    "entityTableName": "book",
+    "databaseType": "sql",
+    "jpaMetamodelFiltering": false,
+    "pagination": "no"
+}
--- a/jhipster-6/bookstore-monolith/.mvn/wrapper/MavenWrapperDownloader.java
+++ b/jhipster-6/bookstore-monolith/.mvn/wrapper/MavenWrapperDownloader.java
@ -0,0 +1,110 @@
+/*
+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.
+*/
+
+import java.net.*;
+import java.io.*;
+import java.nio.channels.*;
+import java.util.Properties;
+
+public class MavenWrapperDownloader {
+
+    /**
+     * 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/0.4.2/maven-wrapper-0.4.2.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 direcrory '" + 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 {
+        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();
+    }
+
+}
--- a/jhipster-6/bookstore-monolith/.mvn/wrapper/maven-wrapper.jar
+++ b/jhipster-6/bookstore-monolith/.mvn/wrapper/maven-wrapper.jar
--- a/jhipster-6/bookstore-monolith/.mvn/wrapper/maven-wrapper.properties
+++ b/jhipster-6/bookstore-monolith/.mvn/wrapper/maven-wrapper.properties
@ -0,0 +1 @@
+distributionUrl=https://repo.maven.apache.org/maven2/org/apache/maven/apache-maven/3.6.0/apache-maven-3.6.0-bin.zip
--- a/jhipster-6/bookstore-monolith/.prettierignore
+++ b/jhipster-6/bookstore-monolith/.prettierignore
@ -0,0 +1,3 @@
+node_modules
+target
+package-lock.json
--- a/jhipster-6/bookstore-monolith/.prettierrc
+++ b/jhipster-6/bookstore-monolith/.prettierrc
@ -0,0 +1,12 @@
+# Prettier configuration
+
+printWidth: 140
+singleQuote: true
+tabWidth: 4
+useTabs: false
+
+# js and ts rules:
+arrowParens: avoid
+
+# jsx and tsx rules:
+jsxBracketSameLine: false
--- a/jhipster-6/bookstore-monolith/.yo-rc.json
+++ b/jhipster-6/bookstore-monolith/.yo-rc.json
@ -0,0 +1,36 @@
+{
+  "generator-jhipster": {
+    "promptValues": {
+      "packageName": "com.baeldung.jhipster5"
+    },
+    "jhipsterVersion": "6.0.0",
+    "applicationType": "monolith",
+    "baseName": "Bookstore",
+    "packageName": "com.baeldung.jhipster5",
+    "packageFolder": "com/baeldung/jhipster5",
+    "serverPort": "8080",
+    "authenticationType": "jwt",
+    "cacheProvider": "no",
+    "websocket": false,
+    "databaseType": "sql",
+    "devDatabaseType": "h2Memory",
+    "prodDatabaseType": "mysql",
+    "searchEngine": false,
+    "messageBroker": false,
+    "serviceDiscoveryType": false,
+    "buildTool": "maven",
+    "enableSwaggerCodegen": false,
+    "jwtSecretKey": "NDJmOTVlZjI2NzhlZDRjNmVkNTM1NDE2NjkyNDljZDJiNzBlMjI5YmZjMjY3MzdjZmZlMjI3NjE4OTRkNzc5MWYzNDNlYWMzYmJjOWRmMjc5ZWQyZTZmOWZkOTMxZWZhNWE1MTVmM2U2NjFmYjhlNDc2Y2Q3NzliMGY0YzFkNmI=",
+    "clientFramework": "angularX",
+    "useSass": true,
+    "clientPackageManager": "npm",
+    "testFrameworks": [],
+    "jhiPrefix": "jhi",
+    "entitySuffix": "",
+    "dtoSuffix": "DTO",
+    "otherModules": [],
+    "enableTranslation": false,
+    "enableHibernateCache": false,
+    "clientTheme": "none"
+  }
+}
--- a/jhipster-6/bookstore-monolith/README.md
+++ b/jhipster-6/bookstore-monolith/README.md
@ -0,0 +1,5 @@
+## Relevant articles:
+
+- [Creating New APIs and Views in JHipster](https://www.baeldung.com/jhipster-new-apis-and-views)
+- [JHipster Authentication with an External Service](https://www.baeldung.com/jhipster-authentication-external-service)
+
--- a/jhipster-6/bookstore-monolith/angular.json
+++ b/jhipster-6/bookstore-monolith/angular.json
@ -0,0 +1,39 @@
+{
+    "$schema": "./node_modules/@angular/cli/lib/config/schema.json",
+    "version": 1,
+    "newProjectRoot": "projects",
+    "projects": {
+        "bookstore": {
+            "root": "",
+            "sourceRoot": "src/main/webapp",
+            "projectType": "application",
+            "architect": {}
+        }
+    },
+    "defaultProject": "bookstore",
+    "cli": {
+        "packageManager": "npm"
+    },
+    "schematics": {
+        "@schematics/angular:component": {
+            "inlineStyle": true,
+            "inlineTemplate": false,
+            "spec": false,
+            "prefix": "jhi",
+            "styleExt": "scss"
+        },
+        "@schematics/angular:directive": {
+            "spec": false,
+            "prefix": "jhi"
+        },
+        "@schematics/angular:guard": {
+            "spec": false
+        },
+        "@schematics/angular:pipe": {
+            "spec": false
+        },
+        "@schematics/angular:service": {
+            "spec": false
+        }
+    }
+}
--- a/jhipster-6/bookstore-monolith/mvnw
+++ b/jhipster-6/bookstore-monolith/mvnw
@ -0,0 +1,286 @@
+#!/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.
+# ----------------------------------------------------------------------------
+
+# ----------------------------------------------------------------------------
+# Maven2 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 "$JAVA_HOME"; pwd)`"
+  # TODO classpath?
+fi
+
+if [ -z "$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
+    jarUrl="https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/0.4.2/maven-wrapper-0.4.2.jar"
+    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 command -v wget > /dev/null; then
+        if [ "$MVNW_VERBOSE" = true ]; then
+          echo "Found wget ... using wget"
+        fi
+        wget "$jarUrl" -O "$wrapperJarPath"
+    elif command -v curl > /dev/null; then
+        if [ "$MVNW_VERBOSE" = true ]; then
+          echo "Found curl ... using curl"
+        fi
+        curl -o "$wrapperJarPath" "$jarUrl"
+    else
+        if [ "$MVNW_VERBOSE" = true ]; then
+          echo "Falling back to using Java to download"
+        fi
+        javaClass="$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.java"
+        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 "$MAVEN_PROJECTBASEDIR"`
+fi
+
+WRAPPER_LAUNCHER=org.apache.maven.wrapper.MavenWrapperMain
+
+exec "$JAVACMD" \
+  $MAVEN_OPTS \
+  -classpath "$MAVEN_PROJECTBASEDIR/.mvn/wrapper/maven-wrapper.jar" \
+  "-Dmaven.home=${M2_HOME}" "-Dmaven.multiModuleProjectDirectory=${MAVEN_PROJECTBASEDIR}" \
+  ${WRAPPER_LAUNCHER} $MAVEN_CONFIG "$@"
--- a/jhipster-6/bookstore-monolith/mvnw.cmd
+++ b/jhipster-6/bookstore-monolith/mvnw.cmd
@ -0,0 +1,161 @@
+@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 Maven2 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 key stroke 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 my 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/0.4.2/maven-wrapper-0.4.2.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% (
+    echo Found %WRAPPER_JAR%
+) else (
+    echo Couldn't find %WRAPPER_JAR%, downloading it ...
+	echo Downloading from: %DOWNLOAD_URL%
+    powershell -Command "(New-Object Net.WebClient).DownloadFile('%DOWNLOAD_URL%', '%WRAPPER_JAR%')"
+    echo Finished downloading %WRAPPER_JAR%
+)
+@REM End of extension
+
+%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%
--- a/jhipster-6/bookstore-monolith/package.json
+++ b/jhipster-6/bookstore-monolith/package.json
@ -0,0 +1,128 @@
+{
+    "name": "bookstore",
+    "version": "0.0.0",
+    "description": "Description for Bookstore",
+    "private": true,
+    "license": "UNLICENSED",
+    "cacheDirectories": [
+        "node_modules"
+    ],
+    "dependencies": {
+        "@angular/common": "7.2.4",
+        "@angular/compiler": "7.2.4",
+        "@angular/core": "7.2.4",
+        "@angular/forms": "7.2.4",
+        "@angular/platform-browser": "7.2.4",
+        "@angular/platform-browser-dynamic": "7.2.4",
+        "@angular/router": "7.2.4",
+        "@fortawesome/angular-fontawesome": "0.3.0",
+        "@fortawesome/fontawesome-svg-core": "1.2.14",
+        "@fortawesome/free-solid-svg-icons": "5.7.1",
+        "@ng-bootstrap/ng-bootstrap": "4.0.2",
+        "@ngx-translate/core": "11.0.1",
+        "@ngx-translate/http-loader": "4.0.0",
+        "bootstrap": "4.2.1",
+        "core-js": "2.6.4",
+        "moment": "2.24.0",
+        "ng-jhipster": "0.9.1",
+        "ngx-cookie": "2.0.1",
+        "ngx-infinite-scroll": "7.0.1",
+        "ngx-webstorage": "2.0.1",
+        "rxjs": "6.4.0",
+        "swagger-ui": "2.2.10",
+        "tslib": "1.9.3",
+        "zone.js": "0.8.29"
+    },
+    "devDependencies": {
+        "@angular/cli": "7.3.1",
+        "@angular/compiler-cli": "7.2.4",
+        "@ngtools/webpack": "7.3.1",
+        "@types/jest": "24.0.0",
+        "@types/node": "10.12.24",
+        "angular-router-loader": "0.8.5",
+        "angular2-template-loader": "0.6.2",
+        "autoprefixer": "9.4.7",
+        "browser-sync": "2.26.3",
+        "browser-sync-webpack-plugin": "2.2.2",
+        "cache-loader": "2.0.1",
+        "codelyzer": "4.5.0",
+        "copy-webpack-plugin": "4.6.0",
+        "css-loader": "2.1.0",
+        "file-loader": "3.0.1",
+        "fork-ts-checker-webpack-plugin": "0.5.2",
+        "friendly-errors-webpack-plugin": "1.7.0",
+        "generator-jhipster": "6.0.0",
+        "html-loader": "0.5.5",
+        "html-webpack-plugin": "3.2.0",
+        "husky": "1.3.1",
+        "jest": "24.1.0",
+        "jest-junit": "6.2.1",
+        "jest-preset-angular": "6.0.2",
+        "jest-sonar-reporter": "2.0.0",
+        "lint-staged": "8.1.3",
+        "mini-css-extract-plugin": "0.5.0",
+        "moment-locales-webpack-plugin": "1.0.7",
+        "optimize-css-assets-webpack-plugin": "5.0.1",
+        "prettier": "1.16.4",
+        "reflect-metadata": "0.1.13",
+        "rimraf": "2.6.3",
+        "simple-progress-webpack-plugin": "1.1.2",
+        "style-loader": "0.23.1",
+        "terser-webpack-plugin": "1.2.2",
+        "thread-loader": "2.1.2",
+        "to-string-loader": "1.1.5",
+        "ts-loader": "5.3.3",
+        "tslint": "5.12.1",
+        "tslint-config-prettier": "1.18.0",
+        "tslint-loader": "3.6.0",
+        "typescript": "3.2.4",
+        "sass": "1.17.0",
+        "sass-loader": "7.1.0",
+        "postcss-loader": "3.0.0",
+        "xml2js": "0.4.19",
+        "webpack": "4.29.3",
+        "webpack-cli": "3.2.3",
+        "webpack-dev-server": "3.1.14",
+        "webpack-merge": "4.2.1",
+        "webpack-notifier": "1.7.0",
+        "webpack-visualizer-plugin": "0.1.11",
+        "workbox-webpack-plugin": "3.6.3",
+        "write-file-webpack-plugin": "4.5.0"
+    },
+    "engines": {
+        "node": ">=8.9.0"
+    },
+    "lint-staged": {
+        "{,src/**/}*.{md,json,ts,css,scss}": [
+            "prettier --write",
+            "git add"
+        ]
+    },
+    "scripts": {
+        "prettier:format": "prettier --write \"{,src/**/}*.{md,json,ts,css,scss}\"",
+        "lint": "tslint --project tsconfig.json -e 'node_modules/**'",
+        "lint:fix": "npm run lint -- --fix",
+        "ngc": "ngc -p tsconfig-aot.json",
+        "cleanup": "rimraf target/{aot,www}",
+        "clean-www": "rimraf target//www/app/{src,target/}",
+        "start": "npm run webpack:dev",
+        "start-tls": "npm run webpack:dev -- --env.tls",
+        "serve": "npm run start",
+        "build": "npm run webpack:prod",
+        "test": "npm run lint && jest --coverage --logHeapUsage -w=2 --config src/test/javascript/jest.conf.js",
+        "test:watch": "npm run test -- --watch",
+        "webpack:dev": "npm run webpack-dev-server -- --config webpack/webpack.dev.js --inline --hot --port=9060 --watch-content-base --env.stats=minimal",
+        "webpack:dev-verbose": "npm run webpack-dev-server -- --config webpack/webpack.dev.js --inline --hot --port=9060 --watch-content-base --profile --progress --env.stats=normal",
+        "webpack:build:main": "npm run webpack -- --config webpack/webpack.dev.js --env.stats=minimal",
+        "webpack:build": "npm run cleanup && npm run webpack:build:main",
+        "webpack:prod:main": "npm run webpack -- --config webpack/webpack.prod.js --profile",
+        "webpack:prod": "npm run cleanup && npm run webpack:prod:main && npm run clean-www",
+        "webpack:test": "npm run test",
+        "webpack-dev-server": "node --max_old_space_size=4096 node_modules/webpack-dev-server/bin/webpack-dev-server.js",
+        "webpack": "node --max_old_space_size=4096 node_modules/webpack/bin/webpack.js"
+    },
+    "jestSonar": {
+        "reportPath": "target/test-results/jest",
+        "reportFile": "TESTS-results-sonar.xml"
+    }
+}
--- a/jhipster-6/bookstore-monolith/pom.xml
+++ b/jhipster-6/bookstore-monolith/pom.xml
--- a/jhipster-6/bookstore-monolith/postcss.config.js
+++ b/jhipster-6/bookstore-monolith/postcss.config.js
@ -0,0 +1,5 @@
+module.exports = {
+    plugins: [
+        require('autoprefixer')
+    ]
+}
--- a/jhipster-6/bookstore-monolith/proxy.conf.json
+++ b/jhipster-6/bookstore-monolith/proxy.conf.json
@ -0,0 +1,7 @@
+{
+    "*": {
+        "target": "http://localhost:8080",
+        "secure": false,
+        "loglevel": "debug"
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/docker/.dockerignore
+++ b/jhipster-6/bookstore-monolith/src/main/docker/.dockerignore
@ -0,0 +1,14 @@
+# https://docs.docker.com/engine/reference/builder/#dockerignore-file
+classes/
+generated-sources/
+generated-test-sources/
+h2db/
+maven-archiver/
+maven-status/
+reports/
+surefire-reports/
+test-classes/
+test-results/
+www/
+!*.jar
+!*.war
--- a/jhipster-6/bookstore-monolith/src/main/docker/Dockerfile
+++ b/jhipster-6/bookstore-monolith/src/main/docker/Dockerfile
@ -0,0 +1,20 @@
+FROM openjdk:8-jre-alpine
+
+ENV SPRING_OUTPUT_ANSI_ENABLED=ALWAYS \
+    JHIPSTER_SLEEP=0 \
+    JAVA_OPTS=""
+
+# Add a jhipster user to run our application so that it doesn't need to run as root
+RUN adduser -D -s /bin/sh jhipster
+WORKDIR /home/jhipster
+
+ADD entrypoint.sh entrypoint.sh
+RUN chmod 755 entrypoint.sh && chown jhipster:jhipster entrypoint.sh
+USER jhipster
+
+ENTRYPOINT ["./entrypoint.sh"]
+
+EXPOSE 8080
+
+ADD *.war app.war
+
--- a/jhipster-6/bookstore-monolith/src/main/docker/app.yml
+++ b/jhipster-6/bookstore-monolith/src/main/docker/app.yml
@ -0,0 +1,15 @@
+version: '2'
+services:
+    bookstore-app:
+        image: bookstore
+        environment:
+            - _JAVA_OPTIONS=-Xmx512m -Xms256m
+            - SPRING_PROFILES_ACTIVE=prod,swagger
+            - SPRING_DATASOURCE_URL=jdbc:mysql://bookstore-mysql:3306/bookstore?useUnicode=true&characterEncoding=utf8&useSSL=false
+            - JHIPSTER_SLEEP=10 # gives time for the database to boot before the application
+        ports:
+            - 8080:8080
+    bookstore-mysql:
+        extends:
+            file: mysql.yml
+            service: bookstore-mysql
--- a/jhipster-6/bookstore-monolith/src/main/docker/entrypoint.sh
+++ b/jhipster-6/bookstore-monolith/src/main/docker/entrypoint.sh
@ -0,0 +1,4 @@
+#!/bin/sh
+
+echo "The application will start in ${JHIPSTER_SLEEP}s..." && sleep ${JHIPSTER_SLEEP}
+exec java ${JAVA_OPTS} -Djava.security.egd=file:/dev/./urandom -jar "${HOME}/app.war" "$@"
--- a/jhipster-6/bookstore-monolith/src/main/docker/grafana/provisioning/dashboards/JVM.json
+++ b/jhipster-6/bookstore-monolith/src/main/docker/grafana/provisioning/dashboards/JVM.json
--- a/jhipster-6/bookstore-monolith/src/main/docker/grafana/provisioning/dashboards/dashboard.yml
+++ b/jhipster-6/bookstore-monolith/src/main/docker/grafana/provisioning/dashboards/dashboard.yml
@ -0,0 +1,11 @@
+apiVersion: 1
+
+providers:
+    - name: 'Prometheus'
+      orgId: 1
+      folder: ''
+      type: file
+      disableDeletion: false
+      editable: true
+      options:
+          path: /etc/grafana/provisioning/dashboards
--- a/jhipster-6/bookstore-monolith/src/main/docker/grafana/provisioning/datasources/datasource.yml
+++ b/jhipster-6/bookstore-monolith/src/main/docker/grafana/provisioning/datasources/datasource.yml
@ -0,0 +1,50 @@
+apiVersion: 1
+
+# list of datasources that should be deleted from the database
+deleteDatasources:
+    - name: Prometheus
+      orgId: 1
+
+# list of datasources to insert/update depending
+# whats available in the database
+datasources:
+    # <string, required> name of the datasource. Required
+    - name: Prometheus
+      # <string, required> datasource type. Required
+      type: prometheus
+      # <string, required> access mode. direct or proxy. Required
+      access: proxy
+      # <int> org id. will default to orgId 1 if not specified
+      orgId: 1
+      # <string> url
+      # On MacOS, replace localhost by host.docker.internal
+      url: http://localhost:9090
+      # <string> database password, if used
+      password:
+      # <string> database user, if used
+      user:
+      # <string> database name, if used
+      database:
+      # <bool> enable/disable basic auth
+      basicAuth: false
+      # <string> basic auth username
+      basicAuthUser: admin
+      # <string> basic auth password
+      basicAuthPassword: admin
+      # <bool> enable/disable with credentials headers
+      withCredentials:
+      # <bool> mark as default datasource. Max one per org
+      isDefault: true
+      # <map> fields that will be converted to json and stored in json_data
+      jsonData:
+          graphiteVersion: '1.1'
+          tlsAuth: false
+          tlsAuthWithCACert: false
+      # <string> json object of data that will be encrypted.
+      secureJsonData:
+          tlsCACert: '...'
+          tlsClientCert: '...'
+          tlsClientKey: '...'
+      version: 1
+      # <bool> allow users to edit datasources from the UI.
+      editable: true
--- a/jhipster-6/bookstore-monolith/src/main/docker/monitoring.yml
+++ b/jhipster-6/bookstore-monolith/src/main/docker/monitoring.yml
@ -0,0 +1,26 @@
+version: '3'
+services:
+    bookstore-prometheus:
+        image: prom/prometheus:v2.9.2
+        volumes:
+            - ./prometheus/:/etc/prometheus/
+        command:
+            - '--config.file=/etc/prometheus/prometheus.yml'
+        ports:
+            - 9090:9090
+        # On MacOS, remove next line and replace localhost by host.docker.internal in prometheus/prometheus.yml and
+        # grafana/provisioning/datasources/datasource.yml
+        network_mode: 'host' # to test locally running service
+    bookstore-grafana:
+        image: grafana/grafana:6.1.4
+        volumes:
+            - ./grafana/provisioning/:/etc/grafana/provisioning/
+        environment:
+            - GF_SECURITY_ADMIN_PASSWORD=admin
+            - GF_USERS_ALLOW_SIGN_UP=false
+            - GF_INSTALL_PLUGINS=grafana-piechart-panel
+        ports:
+            - 3000:3000
+        # On MacOS, remove next line and replace localhost by host.docker.internal in prometheus/prometheus.yml and
+        # grafana/provisioning/datasources/datasource.yml
+        network_mode: 'host' # to test locally running service
--- a/jhipster-6/bookstore-monolith/src/main/docker/mysql.yml
+++ b/jhipster-6/bookstore-monolith/src/main/docker/mysql.yml
@ -0,0 +1,13 @@
+version: '2'
+services:
+    bookstore-mysql:
+        image: mysql:5.7.20
+        # volumes:
+        #     - ~/volumes/jhipster/Bookstore/mysql/:/var/lib/mysql/
+        environment:
+            - MYSQL_USER=root
+            - MYSQL_ALLOW_EMPTY_PASSWORD=yes
+            - MYSQL_DATABASE=bookstore
+        ports:
+            - 3306:3306
+        command: mysqld --lower_case_table_names=1 --skip-ssl --character_set_server=utf8mb4 --explicit_defaults_for_timestamp
--- a/jhipster-6/bookstore-monolith/src/main/docker/prometheus/prometheus.yml
+++ b/jhipster-6/bookstore-monolith/src/main/docker/prometheus/prometheus.yml
@ -0,0 +1,26 @@
+# Sample global config for monitoring JHipster applications
+global:
+    scrape_interval: 15s # By default, scrape targets every 15 seconds.
+    evaluation_interval: 15s # By default, scrape targets every 15 seconds.
+    # scrape_timeout is set to the global default (10s).
+
+    # Attach these labels to any time series or alerts when communicating with
+    # external systems (federation, remote storage, Alertmanager).
+    external_labels:
+        monitor: 'jhipster'
+
+# A scrape configuration containing exactly one endpoint to scrape:
+# Here it's Prometheus itself.
+scrape_configs:
+    # The job name is added as a label `job=<job_name>` to any timeseries scraped from this config.
+    - job_name: 'prometheus'
+
+      # Override the global default and scrape targets from this job every 5 seconds.
+      scrape_interval: 5s
+
+      # scheme defaults to 'http'.
+      metrics_path: /management/prometheus
+      static_configs:
+          - targets:
+                # On MacOS, replace localhost by host.docker.internal
+                - localhost:8080
--- a/jhipster-6/bookstore-monolith/src/main/docker/sonar.yml
+++ b/jhipster-6/bookstore-monolith/src/main/docker/sonar.yml
@ -0,0 +1,7 @@
+version: '2'
+services:
+    bookstore-sonar:
+        image: sonarqube:7.1
+        ports:
+            - 9001:9000
+            - 9092:9092
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/ApplicationWebXml.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/ApplicationWebXml.java
@ -0,0 +1,21 @@
+package com.baeldung.jhipster6;
+
+import com.baeldung.jhipster6.config.DefaultProfileUtil;
+import org.springframework.boot.builder.SpringApplicationBuilder;
+import org.springframework.boot.web.servlet.support.SpringBootServletInitializer;
+
+/**
+ * This is a helper Java class that provides an alternative to creating a web.xml.
+ * This will be invoked only when the application is deployed to a Servlet container like Tomcat, JBoss etc.
+ */
+public class ApplicationWebXml extends SpringBootServletInitializer {
+
+    @Override
+    protected SpringApplicationBuilder configure(SpringApplicationBuilder application) {
+        /**
+         * set a default to use when no profile is configured.
+         */
+        DefaultProfileUtil.addDefaultProfile(application.application());
+        return application.sources(BookstoreApp.class);
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/BookstoreApp.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/BookstoreApp.java
@ -0,0 +1,98 @@
+package com.baeldung.jhipster6;
+
+import com.baeldung.jhipster6.config.ApplicationProperties;
+import com.baeldung.jhipster6.config.DefaultProfileUtil;
+
+import io.github.jhipster.config.JHipsterConstants;
+
+import org.apache.commons.lang3.StringUtils;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.boot.autoconfigure.liquibase.LiquibaseProperties;
+import org.springframework.boot.context.properties.EnableConfigurationProperties;
+import org.springframework.core.env.Environment;
+
+import javax.annotation.PostConstruct;
+import java.net.InetAddress;
+import java.net.UnknownHostException;
+import java.util.Arrays;
+import java.util.Collection;
+
+@SpringBootApplication
+@EnableConfigurationProperties({LiquibaseProperties.class, ApplicationProperties.class})
+public class BookstoreApp {
+
+    private static final Logger log = LoggerFactory.getLogger(BookstoreApp.class);
+
+    private final Environment env;
+
+    public BookstoreApp(Environment env) {
+        this.env = env;
+    }
+
+    /**
+     * Initializes Bookstore.
+     * <p>
+     * Spring profiles can be configured with a program argument --spring.profiles.active=your-active-profile
+     * <p>
+     * You can find more information on how profiles work with JHipster on <a href="https://www.jhipster.tech/profiles/">https://www.jhipster.tech/profiles/</a>.
+     */
+    @PostConstruct
+    public void initApplication() {
+        Collection<String> activeProfiles = Arrays.asList(env.getActiveProfiles());
+        if (activeProfiles.contains(JHipsterConstants.SPRING_PROFILE_DEVELOPMENT) && activeProfiles.contains(JHipsterConstants.SPRING_PROFILE_PRODUCTION)) {
+            log.error("You have misconfigured your application! It should not run " +
+                "with both the 'dev' and 'prod' profiles at the same time.");
+        }
+        if (activeProfiles.contains(JHipsterConstants.SPRING_PROFILE_DEVELOPMENT) && activeProfiles.contains(JHipsterConstants.SPRING_PROFILE_CLOUD)) {
+            log.error("You have misconfigured your application! It should not " +
+                "run with both the 'dev' and 'cloud' profiles at the same time.");
+        }
+    }
+
+    /**
+     * Main method, used to run the application.
+     *
+     * @param args the command line arguments
+     */
+    public static void main(String[] args) {
+        SpringApplication app = new SpringApplication(BookstoreApp.class);
+        DefaultProfileUtil.addDefaultProfile(app);
+        Environment env = app.run(args).getEnvironment();
+        logApplicationStartup(env);
+    }
+
+    private static void logApplicationStartup(Environment env) {
+        String protocol = "http";
+        if (env.getProperty("server.ssl.key-store") != null) {
+            protocol = "https";
+        }
+        String serverPort = env.getProperty("server.port");
+        String contextPath = env.getProperty("server.servlet.context-path");
+        if (StringUtils.isBlank(contextPath)) {
+            contextPath = "/";
+        }
+        String hostAddress = "localhost";
+        try {
+            hostAddress = InetAddress.getLocalHost().getHostAddress();
+        } catch (UnknownHostException e) {
+            log.warn("The host name could not be determined, using `localhost` as fallback");
+        }
+        log.info("\n----------------------------------------------------------\n\t" +
+                "Application '{}' is running! Access URLs:\n\t" +
+                "Local: \t\t{}://localhost:{}{}\n\t" +
+                "External: \t{}://{}:{}{}\n\t" +
+                "Profile(s): \t{}\n----------------------------------------------------------",
+            env.getProperty("spring.application.name"),
+            protocol,
+            serverPort,
+            contextPath,
+            protocol,
+            hostAddress,
+            serverPort,
+            contextPath,
+            env.getActiveProfiles());
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/aop/logging/LoggingAspect.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/aop/logging/LoggingAspect.java
@ -0,0 +1,98 @@
+package com.baeldung.jhipster6.aop.logging;
+
+import io.github.jhipster.config.JHipsterConstants;
+
+import org.aspectj.lang.JoinPoint;
+import org.aspectj.lang.ProceedingJoinPoint;
+import org.aspectj.lang.annotation.AfterThrowing;
+import org.aspectj.lang.annotation.Around;
+import org.aspectj.lang.annotation.Aspect;
+import org.aspectj.lang.annotation.Pointcut;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.core.env.Environment;
+
+import java.util.Arrays;
+
+/**
+ * Aspect for logging execution of service and repository Spring components.
+ *
+ * By default, it only runs with the "dev" profile.
+ */
+@Aspect
+public class LoggingAspect {
+
+    private final Logger log = LoggerFactory.getLogger(this.getClass());
+
+    private final Environment env;
+
+    public LoggingAspect(Environment env) {
+        this.env = env;
+    }
+
+    /**
+     * Pointcut that matches all repositories, services and Web REST endpoints.
+     */
+    @Pointcut("within(@org.springframework.stereotype.Repository *)" +
+        " || within(@org.springframework.stereotype.Service *)" +
+        " || within(@org.springframework.web.bind.annotation.RestController *)")
+    public void springBeanPointcut() {
+        // Method is empty as this is just a Pointcut, the implementations are in the advices.
+    }
+
+    /**
+     * Pointcut that matches all Spring beans in the application's main packages.
+     */
+    @Pointcut("within(com.baeldung.jhipster5.repository..*)"+
+        " || within(com.baeldung.jhipster5.service..*)"+
+        " || within(com.baeldung.jhipster5.web.rest..*)")
+    public void applicationPackagePointcut() {
+        // Method is empty as this is just a Pointcut, the implementations are in the advices.
+    }
+
+    /**
+     * Advice that logs methods throwing exceptions.
+     *
+     * @param joinPoint join point for advice
+     * @param e exception
+     */
+    @AfterThrowing(pointcut = "applicationPackagePointcut() && springBeanPointcut()", throwing = "e")
+    public void logAfterThrowing(JoinPoint joinPoint, Throwable e) {
+        if (env.acceptsProfiles(JHipsterConstants.SPRING_PROFILE_DEVELOPMENT)) {
+            log.error("Exception in {}.{}() with cause = \'{}\' and exception = \'{}\'", joinPoint.getSignature().getDeclaringTypeName(),
+                joinPoint.getSignature().getName(), e.getCause() != null? e.getCause() : "NULL", e.getMessage(), e);
+
+        } else {
+            log.error("Exception in {}.{}() with cause = {}", joinPoint.getSignature().getDeclaringTypeName(),
+                joinPoint.getSignature().getName(), e.getCause() != null? e.getCause() : "NULL");
+        }
+    }
+
+    /**
+     * Advice that logs when a method is entered and exited.
+     *
+     * @param joinPoint join point for advice
+     * @return result
+     * @throws Throwable throws IllegalArgumentException
+     */
+    @Around("applicationPackagePointcut() && springBeanPointcut()")
+    public Object logAround(ProceedingJoinPoint joinPoint) throws Throwable {
+        if (log.isDebugEnabled()) {
+            log.debug("Enter: {}.{}() with argument[s] = {}", joinPoint.getSignature().getDeclaringTypeName(),
+                joinPoint.getSignature().getName(), Arrays.toString(joinPoint.getArgs()));
+        }
+        try {
+            Object result = joinPoint.proceed();
+            if (log.isDebugEnabled()) {
+                log.debug("Exit: {}.{}() with result = {}", joinPoint.getSignature().getDeclaringTypeName(),
+                    joinPoint.getSignature().getName(), result);
+            }
+            return result;
+        } catch (IllegalArgumentException e) {
+            log.error("Illegal argument: {} in {}.{}()", Arrays.toString(joinPoint.getArgs()),
+                joinPoint.getSignature().getDeclaringTypeName(), joinPoint.getSignature().getName());
+
+            throw e;
+        }
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/config/ApplicationProperties.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/config/ApplicationProperties.java
@ -0,0 +1,14 @@
+package com.baeldung.jhipster6.config;
+
+import org.springframework.boot.context.properties.ConfigurationProperties;
+
+/**
+ * Properties specific to Bookstore.
+ * <p>
+ * Properties are configured in the application.yml file.
+ * See {@link io.github.jhipster.config.JHipsterProperties} for a good example.
+ */
+@ConfigurationProperties(prefix = "application", ignoreUnknownFields = false)
+public class ApplicationProperties {
+
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/config/AsyncConfiguration.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/config/AsyncConfiguration.java
@ -0,0 +1,59 @@
+package com.baeldung.jhipster6.config;
+
+import io.github.jhipster.async.ExceptionHandlingAsyncTaskExecutor;
+import io.github.jhipster.config.JHipsterProperties;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.aop.interceptor.AsyncUncaughtExceptionHandler;
+import org.springframework.aop.interceptor.SimpleAsyncUncaughtExceptionHandler;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.scheduling.annotation.*;
+import org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor;
+import org.springframework.scheduling.annotation.SchedulingConfigurer;
+import org.springframework.scheduling.config.ScheduledTaskRegistrar;
+
+import java.util.concurrent.Executor;
+import java.util.concurrent.Executors;
+
+@Configuration
+@EnableAsync
+@EnableScheduling
+public class AsyncConfiguration implements AsyncConfigurer, SchedulingConfigurer {
+
+    private final Logger log = LoggerFactory.getLogger(AsyncConfiguration.class);
+
+    private final JHipsterProperties jHipsterProperties;
+
+    public AsyncConfiguration(JHipsterProperties jHipsterProperties) {
+        this.jHipsterProperties = jHipsterProperties;
+    }
+
+    @Override
+    @Bean(name = "taskExecutor")
+    public Executor getAsyncExecutor() {
+        log.debug("Creating Async Task Executor");
+        ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
+        executor.setCorePoolSize(jHipsterProperties.getAsync().getCorePoolSize());
+        executor.setMaxPoolSize(jHipsterProperties.getAsync().getMaxPoolSize());
+        executor.setQueueCapacity(jHipsterProperties.getAsync().getQueueCapacity());
+        executor.setThreadNamePrefix("bookstore-Executor-");
+        return new ExceptionHandlingAsyncTaskExecutor(executor);
+    }
+
+    @Override
+    public AsyncUncaughtExceptionHandler getAsyncUncaughtExceptionHandler() {
+        return new SimpleAsyncUncaughtExceptionHandler();
+    }
+
+    @Override
+    public void configureTasks(ScheduledTaskRegistrar taskRegistrar) {
+        taskRegistrar.setScheduler(scheduledTaskExecutor());
+    }
+
+    @Bean
+    public Executor scheduledTaskExecutor() {
+        return Executors.newScheduledThreadPool(jHipsterProperties.getAsync().getCorePoolSize());
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/config/CloudDatabaseConfiguration.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/config/CloudDatabaseConfiguration.java
@ -0,0 +1,28 @@
+package com.baeldung.jhipster6.config;
+
+import io.github.jhipster.config.JHipsterConstants;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.cloud.config.java.AbstractCloudConfig;
+import org.springframework.context.annotation.*;
+
+import javax.sql.DataSource;
+import org.springframework.boot.context.properties.ConfigurationProperties;
+
+
+@Configuration
+@Profile(JHipsterConstants.SPRING_PROFILE_CLOUD)
+public class CloudDatabaseConfiguration extends AbstractCloudConfig {
+
+    private final Logger log = LoggerFactory.getLogger(CloudDatabaseConfiguration.class);
+
+    private static final String CLOUD_CONFIGURATION_HIKARI_PREFIX = "spring.datasource.hikari";
+
+    @Bean
+    @ConfigurationProperties(CLOUD_CONFIGURATION_HIKARI_PREFIX)
+    public DataSource dataSource() {
+        log.info("Configuring JDBC datasource from a cloud provider");
+        return connectionFactory().dataSource();
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/config/Constants.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/config/Constants.java
@ -0,0 +1,17 @@
+package com.baeldung.jhipster6.config;
+
+/**
+ * Application constants.
+ */
+public final class Constants {
+
+    // Regex for acceptable logins
+    public static final String LOGIN_REGEX = "^[_.@A-Za-z0-9-]*$";
+
+    public static final String SYSTEM_ACCOUNT = "system";
+    public static final String ANONYMOUS_USER = "anonymoususer";
+    public static final String DEFAULT_LANGUAGE = "en";
+
+    private Constants() {
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/config/DatabaseConfiguration.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/config/DatabaseConfiguration.java
@ -0,0 +1,59 @@
+package com.baeldung.jhipster6.config;
+
+import io.github.jhipster.config.JHipsterConstants;
+import io.github.jhipster.config.h2.H2ConfigurationHelper;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.context.annotation.Profile;
+
+import org.springframework.core.env.Environment;
+import org.springframework.data.jpa.repository.config.EnableJpaAuditing;
+import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
+import org.springframework.transaction.annotation.EnableTransactionManagement;
+
+import java.sql.SQLException;
+
+@Configuration
+@EnableJpaRepositories("com.baeldung.jhipster5.repository")
+@EnableJpaAuditing(auditorAwareRef = "springSecurityAuditorAware")
+@EnableTransactionManagement
+public class DatabaseConfiguration {
+
+    private final Logger log = LoggerFactory.getLogger(DatabaseConfiguration.class);
+
+    private final Environment env;
+
+    public DatabaseConfiguration(Environment env) {
+        this.env = env;
+    }
+
+    /**
+     * Open the TCP port for the H2 database, so it is available remotely.
+     *
+     * @return the H2 database TCP server
+     * @throws SQLException if the server failed to start
+     */
+    @Bean(initMethod = "start", destroyMethod = "stop")
+    @Profile(JHipsterConstants.SPRING_PROFILE_DEVELOPMENT)
+    public Object h2TCPServer() throws SQLException {
+        String port = getValidPortForH2();
+        log.debug("H2 database is available on port {}", port);
+        return H2ConfigurationHelper.createServer(port);
+    }
+
+    private String getValidPortForH2() {
+        int port = Integer.parseInt(env.getProperty("server.port"));
+        if (port < 10000) {
+            port = 10000 + port;
+        } else {
+            if (port < 63536) {
+                port = port + 2000;
+            } else {
+                port = port - 2000;
+            }
+        }
+        return String.valueOf(port);
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/config/DateTimeFormatConfiguration.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/config/DateTimeFormatConfiguration.java
@ -0,0 +1,20 @@
+package com.baeldung.jhipster6.config;
+
+import org.springframework.context.annotation.Configuration;
+import org.springframework.format.FormatterRegistry;
+import org.springframework.format.datetime.standard.DateTimeFormatterRegistrar;
+import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;
+
+/**
+ * Configure the converters to use the ISO format for dates by default.
+ */
+@Configuration
+public class DateTimeFormatConfiguration implements WebMvcConfigurer {
+
+    @Override
+    public void addFormatters(FormatterRegistry registry) {
+        DateTimeFormatterRegistrar registrar = new DateTimeFormatterRegistrar();
+        registrar.setUseIsoFormat(true);
+        registrar.registerFormatters(registry);
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/config/DefaultProfileUtil.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/config/DefaultProfileUtil.java
@ -0,0 +1,51 @@
+package com.baeldung.jhipster6.config;
+
+import io.github.jhipster.config.JHipsterConstants;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.core.env.Environment;
+
+import java.util.*;
+
+/**
+ * Utility class to load a Spring profile to be used as default
+ * when there is no <code>spring.profiles.active</code> set in the environment or as command line argument.
+ * If the value is not available in <code>application.yml</code> then <code>dev</code> profile will be used as default.
+ */
+public final class DefaultProfileUtil {
+
+    private static final String SPRING_PROFILE_DEFAULT = "spring.profiles.default";
+
+    private DefaultProfileUtil() {
+    }
+
+    /**
+     * Set a default to use when no profile is configured.
+     *
+     * @param app the Spring application
+     */
+    public static void addDefaultProfile(SpringApplication app) {
+        Map<String, Object> defProperties = new HashMap<>();
+        /*
+        * The default profile to use when no other profiles are defined
+        * This cannot be set in the <code>application.yml</code> file.
+        * See https://github.com/spring-projects/spring-boot/issues/1219
+        */
+        defProperties.put(SPRING_PROFILE_DEFAULT, JHipsterConstants.SPRING_PROFILE_DEVELOPMENT);
+        app.setDefaultProperties(defProperties);
+    }
+
+    /**
+     * Get the profiles that are applied else get default profiles.
+     *
+     * @param env spring environment
+     * @return profiles
+     */
+    public static String[] getActiveProfiles(Environment env) {
+        String[] profiles = env.getActiveProfiles();
+        if (profiles.length == 0) {
+            return env.getDefaultProfiles();
+        }
+        return profiles;
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/config/JacksonConfiguration.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/config/JacksonConfiguration.java
@ -0,0 +1,63 @@
+package com.baeldung.jhipster6.config;
+
+import com.fasterxml.jackson.datatype.hibernate5.Hibernate5Module;
+import com.fasterxml.jackson.datatype.jdk8.Jdk8Module;
+import com.fasterxml.jackson.datatype.jsr310.JavaTimeModule;
+import com.fasterxml.jackson.module.afterburner.AfterburnerModule;
+
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.zalando.problem.ProblemModule;
+import org.zalando.problem.violations.ConstraintViolationProblemModule;
+
+@Configuration
+public class JacksonConfiguration {
+
+    /**
+     * Support for Java date and time API.
+     * @return the corresponding Jackson module.
+     */
+    @Bean
+    public JavaTimeModule javaTimeModule() {
+        return new JavaTimeModule();
+    }
+
+    @Bean
+    public Jdk8Module jdk8TimeModule() {
+        return new Jdk8Module();
+    }
+
+
+    /*
+     * Support for Hibernate types in Jackson.
+     */
+    @Bean
+    public Hibernate5Module hibernate5Module() {
+        return new Hibernate5Module();
+    }
+
+    /*
+     * Jackson Afterburner module to speed up serialization/deserialization.
+     */
+    @Bean
+    public AfterburnerModule afterburnerModule() {
+        return new AfterburnerModule();
+    }
+
+    /*
+     * Module for serialization/deserialization of RFC7807 Problem.
+     */
+    @Bean
+    ProblemModule problemModule() {
+        return new ProblemModule();
+    }
+
+    /*
+     * Module for serialization/deserialization of ConstraintViolationProblem.
+     */
+    @Bean
+    ConstraintViolationProblemModule constraintViolationProblemModule() {
+        return new ConstraintViolationProblemModule();
+    }
+
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/config/LiquibaseConfiguration.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/config/LiquibaseConfiguration.java
@ -0,0 +1,50 @@
+package com.baeldung.jhipster6.config;
+
+import javax.sql.DataSource;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.beans.factory.annotation.Qualifier;
+import org.springframework.boot.autoconfigure.liquibase.LiquibaseProperties;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.core.env.Environment;
+import org.springframework.core.task.TaskExecutor;
+
+import io.github.jhipster.config.JHipsterConstants;
+import io.github.jhipster.config.liquibase.AsyncSpringLiquibase;
+import liquibase.integration.spring.SpringLiquibase;
+
+@Configuration
+public class LiquibaseConfiguration {
+
+    private final Logger log = LoggerFactory.getLogger(LiquibaseConfiguration.class);
+
+    private final Environment env;
+
+
+    public LiquibaseConfiguration(Environment env) {
+        this.env = env;
+    }
+
+    @Bean
+    public SpringLiquibase liquibase(@Qualifier("taskExecutor") TaskExecutor taskExecutor,
+            DataSource dataSource, LiquibaseProperties liquibaseProperties) {
+
+        // Use liquibase.integration.spring.SpringLiquibase if you don't want Liquibase to start asynchronously
+        SpringLiquibase liquibase = new AsyncSpringLiquibase(taskExecutor, env);
+        liquibase.setDataSource(dataSource);
+        liquibase.setChangeLog("classpath:config/liquibase/master.xml");
+        liquibase.setContexts(liquibaseProperties.getContexts());
+        liquibase.setDefaultSchema(liquibaseProperties.getDefaultSchema());
+        liquibase.setDropFirst(liquibaseProperties.isDropFirst());
+        liquibase.setChangeLogParameters(liquibaseProperties.getParameters());
+        if (env.acceptsProfiles(JHipsterConstants.SPRING_PROFILE_NO_LIQUIBASE)) {
+            liquibase.setShouldRun(false);
+        } else {
+            liquibase.setShouldRun(liquibaseProperties.isEnabled());
+            log.debug("Configuring Liquibase");
+        }
+        return liquibase;
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/config/LocaleConfiguration.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/config/LocaleConfiguration.java
@ -0,0 +1,27 @@
+package com.baeldung.jhipster6.config;
+
+import io.github.jhipster.config.locale.AngularCookieLocaleResolver;
+
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.web.servlet.LocaleResolver;
+import org.springframework.web.servlet.config.annotation.*;
+import org.springframework.web.servlet.i18n.LocaleChangeInterceptor;
+
+@Configuration
+public class LocaleConfiguration implements WebMvcConfigurer {
+
+    @Bean(name = "localeResolver")
+    public LocaleResolver localeResolver() {
+        AngularCookieLocaleResolver cookieLocaleResolver = new AngularCookieLocaleResolver();
+        cookieLocaleResolver.setCookieName("NG_TRANSLATE_LANG_KEY");
+        return cookieLocaleResolver;
+    }
+
+    @Override
+    public void addInterceptors(InterceptorRegistry registry) {
+        LocaleChangeInterceptor localeChangeInterceptor = new LocaleChangeInterceptor();
+        localeChangeInterceptor.setParamName("language");
+        registry.addInterceptor(localeChangeInterceptor);
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/config/LoggingAspectConfiguration.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/config/LoggingAspectConfiguration.java
@ -0,0 +1,19 @@
+package com.baeldung.jhipster6.config;
+
+import com.baeldung.jhipster6.aop.logging.LoggingAspect;
+
+import io.github.jhipster.config.JHipsterConstants;
+
+import org.springframework.context.annotation.*;
+import org.springframework.core.env.Environment;
+
+@Configuration
+@EnableAspectJAutoProxy
+public class LoggingAspectConfiguration {
+
+    @Bean
+    @Profile(JHipsterConstants.SPRING_PROFILE_DEVELOPMENT)
+    public LoggingAspect loggingAspect(Environment env) {
+        return new LoggingAspect(env);
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/config/LoggingConfiguration.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/config/LoggingConfiguration.java
@ -0,0 +1,154 @@
+package com.baeldung.jhipster6.config;
+
+import java.net.InetSocketAddress;
+import java.util.Iterator;
+
+import io.github.jhipster.config.JHipsterProperties;
+
+import ch.qos.logback.classic.AsyncAppender;
+import ch.qos.logback.classic.Level;
+import ch.qos.logback.classic.LoggerContext;
+import ch.qos.logback.classic.boolex.OnMarkerEvaluator;
+import ch.qos.logback.classic.spi.ILoggingEvent;
+import ch.qos.logback.classic.spi.LoggerContextListener;
+import ch.qos.logback.core.Appender;
+import ch.qos.logback.core.filter.EvaluatorFilter;
+import ch.qos.logback.core.spi.ContextAwareBase;
+import ch.qos.logback.core.spi.FilterReply;
+import net.logstash.logback.appender.LogstashTcpSocketAppender;
+import net.logstash.logback.encoder.LogstashEncoder;
+import net.logstash.logback.stacktrace.ShortenedThrowableConverter;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.context.annotation.Configuration;
+
+@Configuration
+public class LoggingConfiguration {
+
+    private static final String LOGSTASH_APPENDER_NAME = "LOGSTASH";
+
+    private static final String ASYNC_LOGSTASH_APPENDER_NAME = "ASYNC_LOGSTASH";
+
+    private final Logger log = LoggerFactory.getLogger(LoggingConfiguration.class);
+
+    private LoggerContext context = (LoggerContext) LoggerFactory.getILoggerFactory();
+
+    private final String appName;
+
+    private final String serverPort;
+
+    private final JHipsterProperties jHipsterProperties;
+
+    public LoggingConfiguration(@Value("${spring.application.name}") String appName, @Value("${server.port}") String serverPort,
+         JHipsterProperties jHipsterProperties) {
+        this.appName = appName;
+        this.serverPort = serverPort;
+        this.jHipsterProperties = jHipsterProperties;
+        if (jHipsterProperties.getLogging().getLogstash().isEnabled()) {
+            addLogstashAppender(context);
+            addContextListener(context);
+        }
+        if (jHipsterProperties.getMetrics().getLogs().isEnabled()) {
+            setMetricsMarkerLogbackFilter(context);
+        }
+    }
+
+    private void addContextListener(LoggerContext context) {
+        LogbackLoggerContextListener loggerContextListener = new LogbackLoggerContextListener();
+        loggerContextListener.setContext(context);
+        context.addListener(loggerContextListener);
+    }
+
+    private void addLogstashAppender(LoggerContext context) {
+        log.info("Initializing Logstash logging");
+
+        LogstashTcpSocketAppender logstashAppender = new LogstashTcpSocketAppender();
+        logstashAppender.setName(LOGSTASH_APPENDER_NAME);
+        logstashAppender.setContext(context);
+        String customFields = "{\"app_name\":\"" + appName + "\",\"app_port\":\"" + serverPort + "\"}";
+
+        // More documentation is available at: https://github.com/logstash/logstash-logback-encoder
+        LogstashEncoder logstashEncoder = new LogstashEncoder();
+        // Set the Logstash appender config from JHipster properties
+        logstashAppender.addDestinations(new InetSocketAddress(jHipsterProperties.getLogging().getLogstash().getHost(), jHipsterProperties.getLogging().getLogstash().getPort()));
+
+        ShortenedThrowableConverter throwableConverter = new ShortenedThrowableConverter();
+        throwableConverter.setRootCauseFirst(true);
+        logstashEncoder.setThrowableConverter(throwableConverter);
+        logstashEncoder.setCustomFields(customFields);
+
+        logstashAppender.setEncoder(logstashEncoder);
+        logstashAppender.start();
+
+        // Wrap the appender in an Async appender for performance
+        AsyncAppender asyncLogstashAppender = new AsyncAppender();
+        asyncLogstashAppender.setContext(context);
+        asyncLogstashAppender.setName(ASYNC_LOGSTASH_APPENDER_NAME);
+        asyncLogstashAppender.setQueueSize(jHipsterProperties.getLogging().getLogstash().getQueueSize());
+        asyncLogstashAppender.addAppender(logstashAppender);
+        asyncLogstashAppender.start();
+
+        context.getLogger("ROOT").addAppender(asyncLogstashAppender);
+    }
+
+    // Configure a log filter to remove "metrics" logs from all appenders except the "LOGSTASH" appender
+    private void setMetricsMarkerLogbackFilter(LoggerContext context) {
+        log.info("Filtering metrics logs from all appenders except the {} appender", LOGSTASH_APPENDER_NAME);
+        OnMarkerEvaluator onMarkerMetricsEvaluator = new OnMarkerEvaluator();
+        onMarkerMetricsEvaluator.setContext(context);
+        onMarkerMetricsEvaluator.addMarker("metrics");
+        onMarkerMetricsEvaluator.start();
+        EvaluatorFilter<ILoggingEvent> metricsFilter = new EvaluatorFilter<>();
+        metricsFilter.setContext(context);
+        metricsFilter.setEvaluator(onMarkerMetricsEvaluator);
+        metricsFilter.setOnMatch(FilterReply.DENY);
+        metricsFilter.start();
+
+        for (ch.qos.logback.classic.Logger logger : context.getLoggerList()) {
+            for (Iterator<Appender<ILoggingEvent>> it = logger.iteratorForAppenders(); it.hasNext();) {
+                Appender<ILoggingEvent> appender = it.next();
+                if (!appender.getName().equals(ASYNC_LOGSTASH_APPENDER_NAME)) {
+                    log.debug("Filter metrics logs from the {} appender", appender.getName());
+                    appender.setContext(context);
+                    appender.addFilter(metricsFilter);
+                    appender.start();
+                }
+            }
+        }
+    }
+
+    /**
+     * Logback configuration is achieved by configuration file and API.
+     * When configuration file change is detected, the configuration is reset.
+     * This listener ensures that the programmatic configuration is also re-applied after reset.
+     */
+    class LogbackLoggerContextListener extends ContextAwareBase implements LoggerContextListener {
+
+        @Override
+        public boolean isResetResistant() {
+            return true;
+        }
+
+        @Override
+        public void onStart(LoggerContext context) {
+            addLogstashAppender(context);
+        }
+
+        @Override
+        public void onReset(LoggerContext context) {
+            addLogstashAppender(context);
+        }
+
+        @Override
+        public void onStop(LoggerContext context) {
+            // Nothing to do.
+        }
+
+        @Override
+        public void onLevelChange(ch.qos.logback.classic.Logger logger, Level level) {
+            // Nothing to do.
+        }
+    }
+
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/config/SecurityConfiguration.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/config/SecurityConfiguration.java
@ -0,0 +1,125 @@
+package com.baeldung.jhipster6.config;
+
+import com.baeldung.jhipster6.security.*;
+import com.baeldung.jhipster6.security.jwt.*;
+import com.baeldung.jhipster6.security.AuthoritiesConstants;
+import com.baeldung.jhipster6.security.jwt.JWTConfigurer;
+import com.baeldung.jhipster6.security.jwt.TokenProvider;
+
+import org.springframework.beans.factory.BeanInitializationException;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.context.annotation.Import;
+import org.springframework.http.HttpMethod;
+import org.springframework.security.authentication.AuthenticationManager;
+import org.springframework.security.config.annotation.authentication.builders.AuthenticationManagerBuilder;
+import org.springframework.security.config.annotation.method.configuration.EnableGlobalMethodSecurity;
+import org.springframework.security.config.annotation.web.builders.HttpSecurity;
+import org.springframework.security.config.annotation.web.builders.WebSecurity;
+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.core.userdetails.UserDetailsService;
+import org.springframework.security.crypto.bcrypt.BCryptPasswordEncoder;
+import org.springframework.security.crypto.password.PasswordEncoder;
+import org.springframework.security.web.authentication.UsernamePasswordAuthenticationFilter;
+import org.springframework.web.filter.CorsFilter;
+import org.zalando.problem.spring.web.advice.security.SecurityProblemSupport;
+
+import javax.annotation.PostConstruct;
+
+@Configuration
+@EnableWebSecurity
+@EnableGlobalMethodSecurity(prePostEnabled = true, securedEnabled = true)
+@Import(SecurityProblemSupport.class)
+public class SecurityConfiguration extends WebSecurityConfigurerAdapter {
+
+    private final AuthenticationManagerBuilder authenticationManagerBuilder;
+
+    private final UserDetailsService userDetailsService;
+
+    private final TokenProvider tokenProvider;
+
+    private final CorsFilter corsFilter;
+
+    private final SecurityProblemSupport problemSupport;
+
+    public SecurityConfiguration(AuthenticationManagerBuilder authenticationManagerBuilder, UserDetailsService userDetailsService, TokenProvider tokenProvider, CorsFilter corsFilter, SecurityProblemSupport problemSupport) {
+        this.authenticationManagerBuilder = authenticationManagerBuilder;
+        this.userDetailsService = userDetailsService;
+        this.tokenProvider = tokenProvider;
+        this.corsFilter = corsFilter;
+        this.problemSupport = problemSupport;
+    }
+
+    @PostConstruct
+    public void init() {
+        try {
+            authenticationManagerBuilder
+                .userDetailsService(userDetailsService)
+                .passwordEncoder(passwordEncoder());
+        } catch (Exception e) {
+            throw new BeanInitializationException("Security configuration failed", e);
+        }
+    }
+
+    @Override
+    @Bean
+    public AuthenticationManager authenticationManagerBean() throws Exception {
+        return super.authenticationManagerBean();
+    }
+
+    @Bean
+    public PasswordEncoder passwordEncoder() {
+        return new BCryptPasswordEncoder();
+    }
+
+    @Override
+    public void configure(WebSecurity web) throws Exception {
+        web.ignoring()
+            .antMatchers(HttpMethod.OPTIONS, "/**")
+            .antMatchers("/app/**/*.{js,html}")
+            .antMatchers("/i18n/**")
+            .antMatchers("/content/**")
+            .antMatchers("/h2-console/**")
+            .antMatchers("/swagger-ui/index.html")
+            .antMatchers("/test/**");
+    }
+
+    @Override
+    public void configure(HttpSecurity http) throws Exception {
+        http
+            .csrf()
+            .disable()
+            .addFilterBefore(corsFilter, UsernamePasswordAuthenticationFilter.class)
+            .exceptionHandling()
+            .authenticationEntryPoint(problemSupport)
+            .accessDeniedHandler(problemSupport)
+        .and()
+            .headers()
+            .frameOptions()
+            .disable()
+        .and()
+            .sessionManagement()
+            .sessionCreationPolicy(SessionCreationPolicy.STATELESS)
+        .and()
+            .authorizeRequests()
+            .antMatchers("/api/books/purchase/**").authenticated()
+            .antMatchers("/api/register").permitAll()
+            .antMatchers("/api/activate").permitAll()
+            .antMatchers("/api/authenticate").permitAll()
+            .antMatchers("/api/account/reset-password/init").permitAll()
+            .antMatchers("/api/account/reset-password/finish").permitAll()
+            .antMatchers("/api/**").authenticated()
+            .antMatchers("/management/health").permitAll()
+            .antMatchers("/management/info").permitAll()
+            .antMatchers("/management/**").hasAuthority(AuthoritiesConstants.ADMIN)
+        .and()
+            .apply(securityConfigurerAdapter());
+
+    }
+
+    private JWTConfigurer securityConfigurerAdapter() {
+        return new JWTConfigurer(tokenProvider);
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/config/WebConfigurer.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/config/WebConfigurer.java
@ -0,0 +1,142 @@
+package com.baeldung.jhipster6.config;
+
+import io.github.jhipster.config.JHipsterConstants;
+import io.github.jhipster.config.JHipsterProperties;
+import io.github.jhipster.web.filter.CachingHttpHeadersFilter;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.boot.web.server.*;
+import org.springframework.boot.web.servlet.ServletContextInitializer;
+import org.springframework.boot.web.servlet.server.ConfigurableServletWebServerFactory;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.core.env.Environment;
+import org.springframework.core.env.Profiles;
+import org.springframework.http.MediaType;
+import org.springframework.web.cors.CorsConfiguration;
+import org.springframework.web.cors.UrlBasedCorsConfigurationSource;
+import org.springframework.web.filter.CorsFilter;
+
+import javax.servlet.*;
+import java.io.File;
+import java.io.UnsupportedEncodingException;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.Paths;
+import java.util.*;
+
+import static java.net.URLDecoder.decode;
+
+/**
+ * Configuration of web application with Servlet 3.0 APIs.
+ */
+@Configuration
+public class WebConfigurer implements ServletContextInitializer, WebServerFactoryCustomizer<WebServerFactory> {
+
+    private final Logger log = LoggerFactory.getLogger(WebConfigurer.class);
+
+    private final Environment env;
+
+    private final JHipsterProperties jHipsterProperties;
+
+    public WebConfigurer(Environment env, JHipsterProperties jHipsterProperties) {
+        this.env = env;
+        this.jHipsterProperties = jHipsterProperties;
+    }
+
+    @Override
+    public void onStartup(ServletContext servletContext) throws ServletException {
+        if (env.getActiveProfiles().length != 0) {
+            log.info("Web application configuration, using profiles: {}", (Object[]) env.getActiveProfiles());
+        }
+        EnumSet<DispatcherType> disps = EnumSet.of(DispatcherType.REQUEST, DispatcherType.FORWARD, DispatcherType.ASYNC);
+        if (env.acceptsProfiles(Profiles.of(JHipsterConstants.SPRING_PROFILE_PRODUCTION))) {
+            initCachingHttpHeadersFilter(servletContext, disps);
+        }
+        log.info("Web application fully configured");
+    }
+
+    /**
+     * Customize the Servlet engine: Mime types, the document root, the cache.
+     */
+    @Override
+    public void customize(WebServerFactory server) {
+        setMimeMappings(server);
+        // When running in an IDE or with ./mvnw spring-boot:run, set location of the static web assets.
+        setLocationForStaticAssets(server);
+    }
+
+    private void setMimeMappings(WebServerFactory server) {
+        if (server instanceof ConfigurableServletWebServerFactory) {
+            MimeMappings mappings = new MimeMappings(MimeMappings.DEFAULT);
+            // IE issue, see https://github.com/jhipster/generator-jhipster/pull/711
+            mappings.add("html", MediaType.TEXT_HTML_VALUE + ";charset=" + StandardCharsets.UTF_8.name().toLowerCase());
+            // CloudFoundry issue, see https://github.com/cloudfoundry/gorouter/issues/64
+            mappings.add("json", MediaType.TEXT_HTML_VALUE + ";charset=" + StandardCharsets.UTF_8.name().toLowerCase());
+            ConfigurableServletWebServerFactory servletWebServer = (ConfigurableServletWebServerFactory) server;
+            servletWebServer.setMimeMappings(mappings);
+        }
+    }
+
+    private void setLocationForStaticAssets(WebServerFactory server) {
+        if (server instanceof ConfigurableServletWebServerFactory) {
+            ConfigurableServletWebServerFactory servletWebServer = (ConfigurableServletWebServerFactory) server;
+            File root;
+            String prefixPath = resolvePathPrefix();
+            root = new File(prefixPath + "target/classes/static/");
+            if (root.exists() && root.isDirectory()) {
+                servletWebServer.setDocumentRoot(root);
+            }
+        }
+    }
+
+    /**
+     * Resolve path prefix to static resources.
+     */
+    private String resolvePathPrefix() {
+        String fullExecutablePath;
+        try {
+            fullExecutablePath = decode(this.getClass().getResource("").getPath(), StandardCharsets.UTF_8.name());
+        } catch (UnsupportedEncodingException e) {
+            /* try without decoding if this ever happens */
+            fullExecutablePath = this.getClass().getResource("").getPath();
+        }
+        String rootPath = Paths.get(".").toUri().normalize().getPath();
+        String extractedPath = fullExecutablePath.replace(rootPath, "");
+        int extractionEndIndex = extractedPath.indexOf("target/");
+        if (extractionEndIndex <= 0) {
+            return "";
+        }
+        return extractedPath.substring(0, extractionEndIndex);
+    }
+
+    /**
+     * Initializes the caching HTTP Headers Filter.
+     */
+    private void initCachingHttpHeadersFilter(ServletContext servletContext,
+        EnumSet<DispatcherType> disps) {
+        log.debug("Registering Caching HTTP Headers Filter");
+        FilterRegistration.Dynamic cachingHttpHeadersFilter =
+            servletContext.addFilter("cachingHttpHeadersFilter",
+                new CachingHttpHeadersFilter(jHipsterProperties));
+
+        cachingHttpHeadersFilter.addMappingForUrlPatterns(disps, true, "/i18n/*");
+        cachingHttpHeadersFilter.addMappingForUrlPatterns(disps, true, "/content/*");
+        cachingHttpHeadersFilter.addMappingForUrlPatterns(disps, true, "/app/*");
+        cachingHttpHeadersFilter.setAsyncSupported(true);
+    }
+
+    @Bean
+    public CorsFilter corsFilter() {
+        UrlBasedCorsConfigurationSource source = new UrlBasedCorsConfigurationSource();
+        CorsConfiguration config = jHipsterProperties.getCors();
+        if (config.getAllowedOrigins() != null && !config.getAllowedOrigins().isEmpty()) {
+            log.debug("Registering CORS filter");
+            source.registerCorsConfiguration("/api/**", config);
+            source.registerCorsConfiguration("/management/**", config);
+            source.registerCorsConfiguration("/v2/api-docs", config);
+        }
+        return new CorsFilter(source);
+    }
+
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/config/audit/AuditEventConverter.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/config/audit/AuditEventConverter.java
@ -0,0 +1,86 @@
+package com.baeldung.jhipster6.config.audit;
+
+import com.baeldung.jhipster6.domain.PersistentAuditEvent;
+
+import org.springframework.boot.actuate.audit.AuditEvent;
+import org.springframework.security.web.authentication.WebAuthenticationDetails;
+import org.springframework.stereotype.Component;
+
+import java.util.*;
+
+@Component
+public class AuditEventConverter {
+
+    /**
+     * Convert a list of PersistentAuditEvent to a list of AuditEvent
+     *
+     * @param persistentAuditEvents the list to convert
+     * @return the converted list.
+     */
+    public List<AuditEvent> convertToAuditEvent(Iterable<PersistentAuditEvent> persistentAuditEvents) {
+        if (persistentAuditEvents == null) {
+            return Collections.emptyList();
+        }
+        List<AuditEvent> auditEvents = new ArrayList<>();
+        for (PersistentAuditEvent persistentAuditEvent : persistentAuditEvents) {
+            auditEvents.add(convertToAuditEvent(persistentAuditEvent));
+        }
+        return auditEvents;
+    }
+
+    /**
+     * Convert a PersistentAuditEvent to an AuditEvent
+     *
+     * @param persistentAuditEvent the event to convert
+     * @return the converted list.
+     */
+    public AuditEvent convertToAuditEvent(PersistentAuditEvent persistentAuditEvent) {
+        if (persistentAuditEvent == null) {
+            return null;
+        }
+        return new AuditEvent(persistentAuditEvent.getAuditEventDate(), persistentAuditEvent.getPrincipal(),
+            persistentAuditEvent.getAuditEventType(), convertDataToObjects(persistentAuditEvent.getData()));
+    }
+
+    /**
+     * Internal conversion. This is needed to support the current SpringBoot actuator AuditEventRepository interface
+     *
+     * @param data the data to convert
+     * @return a map of String, Object
+     */
+    public Map<String, Object> convertDataToObjects(Map<String, String> data) {
+        Map<String, Object> results = new HashMap<>();
+
+        if (data != null) {
+            for (Map.Entry<String, String> entry : data.entrySet()) {
+                results.put(entry.getKey(), entry.getValue());
+            }
+        }
+        return results;
+    }
+
+    /**
+     * Internal conversion. This method will allow to save additional data.
+     * By default, it will save the object as string
+     *
+     * @param data the data to convert
+     * @return a map of String, String
+     */
+    public Map<String, String> convertDataToStrings(Map<String, Object> data) {
+        Map<String, String> results = new HashMap<>();
+
+        if (data != null) {
+            for (Map.Entry<String, Object> entry : data.entrySet()) {
+                // Extract the data that will be saved.
+                if (entry.getValue() instanceof WebAuthenticationDetails) {
+                    WebAuthenticationDetails authenticationDetails = (WebAuthenticationDetails) entry.getValue();
+                    results.put("remoteAddress", authenticationDetails.getRemoteAddress());
+                    results.put("sessionId", authenticationDetails.getSessionId());
+                } else {
+                    results.put(entry.getKey(), Objects.toString(entry.getValue()));
+                }
+            }
+        }
+        return results;
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/config/audit/package-info.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/config/audit/package-info.java
@ -0,0 +1,4 @@
+/**
+ * Audit specific code.
+ */
+package com.baeldung.jhipster6.config.audit;
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/config/package-info.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/config/package-info.java
@ -0,0 +1,4 @@
+/**
+ * Spring Framework configuration files.
+ */
+package com.baeldung.jhipster6.config;
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/domain/AbstractAuditingEntity.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/domain/AbstractAuditingEntity.java
@ -0,0 +1,79 @@
+package com.baeldung.jhipster6.domain;
+
+import com.fasterxml.jackson.annotation.JsonIgnore;
+import org.hibernate.envers.Audited;
+import org.springframework.data.annotation.CreatedBy;
+import org.springframework.data.annotation.CreatedDate;
+import org.springframework.data.annotation.LastModifiedBy;
+import org.springframework.data.annotation.LastModifiedDate;
+import org.springframework.data.jpa.domain.support.AuditingEntityListener;
+
+import java.io.Serializable;
+import java.time.Instant;
+import javax.persistence.Column;
+import javax.persistence.EntityListeners;
+import javax.persistence.MappedSuperclass;
+
+/**
+ * Base abstract class for entities which will hold definitions for created, last modified by and created,
+ * last modified by date.
+ */
+@MappedSuperclass
+@Audited
+@EntityListeners(AuditingEntityListener.class)
+public abstract class AbstractAuditingEntity implements Serializable {
+
+    private static final long serialVersionUID = 1L;
+
+    @CreatedBy
+    @Column(name = "created_by", nullable = false, length = 50, updatable = false)
+    @JsonIgnore
+    private String createdBy;
+
+    @CreatedDate
+    @Column(name = "created_date", updatable = false)
+    @JsonIgnore
+    private Instant createdDate = Instant.now();
+
+    @LastModifiedBy
+    @Column(name = "last_modified_by", length = 50)
+    @JsonIgnore
+    private String lastModifiedBy;
+
+    @LastModifiedDate
+    @Column(name = "last_modified_date")
+    @JsonIgnore
+    private Instant lastModifiedDate = Instant.now();
+
+    public String getCreatedBy() {
+        return createdBy;
+    }
+
+    public void setCreatedBy(String createdBy) {
+        this.createdBy = createdBy;
+    }
+
+    public Instant getCreatedDate() {
+        return createdDate;
+    }
+
+    public void setCreatedDate(Instant createdDate) {
+        this.createdDate = createdDate;
+    }
+
+    public String getLastModifiedBy() {
+        return lastModifiedBy;
+    }
+
+    public void setLastModifiedBy(String lastModifiedBy) {
+        this.lastModifiedBy = lastModifiedBy;
+    }
+
+    public Instant getLastModifiedDate() {
+        return lastModifiedDate;
+    }
+
+    public void setLastModifiedDate(Instant lastModifiedDate) {
+        this.lastModifiedDate = lastModifiedDate;
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/domain/Authority.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/domain/Authority.java
@ -0,0 +1,59 @@
+package com.baeldung.jhipster6.domain;
+
+import javax.persistence.Entity;
+import javax.persistence.Id;
+import javax.persistence.Table;
+import javax.persistence.Column;
+import javax.validation.constraints.NotNull;
+import javax.validation.constraints.Size;
+import java.io.Serializable;
+
+/**
+ * An authority (a security role) used by Spring Security.
+ */
+@Entity
+@Table(name = "jhi_authority")
+public class Authority implements Serializable {
+
+    private static final long serialVersionUID = 1L;
+
+    @NotNull
+    @Size(max = 50)
+    @Id
+    @Column(length = 50)
+    private String name;
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) {
+            return true;
+        }
+        if (o == null || getClass() != o.getClass()) {
+            return false;
+        }
+
+        Authority authority = (Authority) o;
+
+        return !(name != null ? !name.equals(authority.name) : authority.name != null);
+    }
+
+    @Override
+    public int hashCode() {
+        return name != null ? name.hashCode() : 0;
+    }
+
+    @Override
+    public String toString() {
+        return "Authority{" +
+            "name='" + name + '\'' +
+            "}";
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/domain/Book.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/domain/Book.java
@ -0,0 +1,153 @@
+package com.baeldung.jhipster6.domain;
+
+
+
+import javax.persistence.*;
+import javax.validation.constraints.*;
+
+import java.io.Serializable;
+import java.time.LocalDate;
+import java.util.Objects;
+
+/**
+ * A Book.
+ */
+@Entity
+@Table(name = "book")
+public class Book implements Serializable {
+
+    private static final long serialVersionUID = 1L;
+
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    private Long id;
+
+    @NotNull
+    @Column(name = "title", nullable = false)
+    private String title;
+
+    @NotNull
+    @Column(name = "author", nullable = false)
+    private String author;
+
+    @NotNull
+    @Column(name = "published", nullable = false)
+    private LocalDate published;
+
+    @NotNull
+    @Min(value = 0)
+    @Column(name = "quantity", nullable = false)
+    private Integer quantity;
+
+    @NotNull
+    @DecimalMin(value = "0")
+    @Column(name = "price", nullable = false)
+    private Double price;
+
+    // jhipster-needle-entity-add-field - JHipster will add fields here, do not remove
+    public Long getId() {
+        return id;
+    }
+
+    public void setId(Long id) {
+        this.id = id;
+    }
+
+    public String getTitle() {
+        return title;
+    }
+
+    public Book title(String title) {
+        this.title = title;
+        return this;
+    }
+
+    public void setTitle(String title) {
+        this.title = title;
+    }
+
+    public String getAuthor() {
+        return author;
+    }
+
+    public Book author(String author) {
+        this.author = author;
+        return this;
+    }
+
+    public void setAuthor(String author) {
+        this.author = author;
+    }
+
+    public LocalDate getPublished() {
+        return published;
+    }
+
+    public Book published(LocalDate published) {
+        this.published = published;
+        return this;
+    }
+
+    public void setPublished(LocalDate published) {
+        this.published = published;
+    }
+
+    public Integer getQuantity() {
+        return quantity;
+    }
+
+    public Book quantity(Integer quantity) {
+        this.quantity = quantity;
+        return this;
+    }
+
+    public void setQuantity(Integer quantity) {
+        this.quantity = quantity;
+    }
+
+    public Double getPrice() {
+        return price;
+    }
+
+    public Book price(Double price) {
+        this.price = price;
+        return this;
+    }
+
+    public void setPrice(Double price) {
+        this.price = price;
+    }
+    // jhipster-needle-entity-add-getters-setters - JHipster will add getters and setters here, do not remove
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) {
+            return true;
+        }
+        if (o == null || getClass() != o.getClass()) {
+            return false;
+        }
+        Book book = (Book) o;
+        if (book.getId() == null || getId() == null) {
+            return false;
+        }
+        return Objects.equals(getId(), book.getId());
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hashCode(getId());
+    }
+
+    @Override
+    public String toString() {
+        return "Book{" +
+            "id=" + getId() +
+            ", title='" + getTitle() + "'" +
+            ", author='" + getAuthor() + "'" +
+            ", published='" + getPublished() + "'" +
+            ", quantity=" + getQuantity() +
+            ", price=" + getPrice() +
+            "}";
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/domain/PersistentAuditEvent.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/domain/PersistentAuditEvent.java
@ -0,0 +1,109 @@
+package com.baeldung.jhipster6.domain;
+
+import javax.persistence.*;
+import javax.validation.constraints.NotNull;
+import java.io.Serializable;
+import java.time.Instant;
+import java.util.HashMap;
+import java.util.Objects;
+import java.util.Map;
+
+/**
+ * Persist AuditEvent managed by the Spring Boot actuator.
+ *
+ * @see org.springframework.boot.actuate.audit.AuditEvent
+ */
+@Entity
+@Table(name = "jhi_persistent_audit_event")
+public class PersistentAuditEvent implements Serializable {
+
+    private static final long serialVersionUID = 1L;
+
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    @Column(name = "event_id")
+    private Long id;
+
+    @NotNull
+    @Column(nullable = false)
+    private String principal;
+
+    @Column(name = "event_date")
+    private Instant auditEventDate;
+
+    @Column(name = "event_type")
+    private String auditEventType;
+
+    @ElementCollection
+    @MapKeyColumn(name = "name")
+    @Column(name = "value")
+    @CollectionTable(name = "jhi_persistent_audit_evt_data", joinColumns=@JoinColumn(name="event_id"))
+    private Map<String, String> data = new HashMap<>();
+
+    public Long getId() {
+        return id;
+    }
+
+    public void setId(Long id) {
+        this.id = id;
+    }
+
+    public String getPrincipal() {
+        return principal;
+    }
+
+    public void setPrincipal(String principal) {
+        this.principal = principal;
+    }
+
+    public Instant getAuditEventDate() {
+        return auditEventDate;
+    }
+
+    public void setAuditEventDate(Instant auditEventDate) {
+        this.auditEventDate = auditEventDate;
+    }
+
+    public String getAuditEventType() {
+        return auditEventType;
+    }
+
+    public void setAuditEventType(String auditEventType) {
+        this.auditEventType = auditEventType;
+    }
+
+    public Map<String, String> getData() {
+        return data;
+    }
+
+    public void setData(Map<String, String> data) {
+        this.data = data;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) {
+            return true;
+        }
+        if (o == null || getClass() != o.getClass()) {
+            return false;
+        }
+
+        PersistentAuditEvent persistentAuditEvent = (PersistentAuditEvent) o;
+        return !(persistentAuditEvent.getId() == null || getId() == null) && Objects.equals(getId(), persistentAuditEvent.getId());
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hashCode(getId());
+    }
+
+    @Override
+    public String toString() {
+        return "PersistentAuditEvent{" +
+            "principal='" + principal + '\'' +
+            ", auditEventDate=" + auditEventDate +
+            ", auditEventType='" + auditEventType + '\'' +
+            '}';
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/domain/User.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/domain/User.java
@ -0,0 +1,231 @@
+package com.baeldung.jhipster6.domain;
+
+import com.baeldung.jhipster6.config.Constants;
+
+import com.fasterxml.jackson.annotation.JsonIgnore;
+import org.apache.commons.lang3.StringUtils;
+import org.hibernate.annotations.BatchSize;
+import javax.validation.constraints.Email;
+
+import javax.persistence.*;
+import javax.validation.constraints.NotNull;
+import javax.validation.constraints.Pattern;
+import javax.validation.constraints.Size;
+import java.io.Serializable;
+import java.util.HashSet;
+import java.util.Locale;
+import java.util.Objects;
+import java.util.Set;
+import java.time.Instant;
+
+/**
+ * A user.
+ */
+@Entity
+@Table(name = "jhi_user")
+
+public class User extends AbstractAuditingEntity implements Serializable {
+
+    private static final long serialVersionUID = 1L;
+
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    private Long id;
+
+    @NotNull
+    @Pattern(regexp = Constants.LOGIN_REGEX)
+    @Size(min = 1, max = 50)
+    @Column(length = 50, unique = true, nullable = false)
+    private String login;
+
+    @JsonIgnore
+    @NotNull
+    @Size(min = 60, max = 60)
+    @Column(name = "password_hash", length = 60, nullable = false)
+    private String password;
+
+    @Size(max = 50)
+    @Column(name = "first_name", length = 50)
+    private String firstName;
+
+    @Size(max = 50)
+    @Column(name = "last_name", length = 50)
+    private String lastName;
+
+    @Email
+    @Size(min = 5, max = 254)
+    @Column(length = 254, unique = true)
+    private String email;
+
+    @NotNull
+    @Column(nullable = false)
+    private boolean activated = false;
+
+    @Size(min = 2, max = 6)
+    @Column(name = "lang_key", length = 6)
+    private String langKey;
+
+    @Size(max = 256)
+    @Column(name = "image_url", length = 256)
+    private String imageUrl;
+
+    @Size(max = 20)
+    @Column(name = "activation_key", length = 20)
+    @JsonIgnore
+    private String activationKey;
+
+    @Size(max = 20)
+    @Column(name = "reset_key", length = 20)
+    @JsonIgnore
+    private String resetKey;
+
+    @Column(name = "reset_date")
+    private Instant resetDate = null;
+
+    @JsonIgnore
+    @ManyToMany
+    @JoinTable(
+        name = "jhi_user_authority",
+        joinColumns = {@JoinColumn(name = "user_id", referencedColumnName = "id")},
+        inverseJoinColumns = {@JoinColumn(name = "authority_name", referencedColumnName = "name")})
+
+    @BatchSize(size = 20)
+    private Set<Authority> authorities = new HashSet<>();
+
+    public Long getId() {
+        return id;
+    }
+
+    public void setId(Long id) {
+        this.id = id;
+    }
+
+    public String getLogin() {
+        return login;
+    }
+
+    // Lowercase the login before saving it in database
+    public void setLogin(String login) {
+        this.login = StringUtils.lowerCase(login, Locale.ENGLISH);
+    }
+
+    public String getPassword() {
+        return password;
+    }
+
+    public void setPassword(String password) {
+        this.password = password;
+    }
+
+    public String getFirstName() {
+        return firstName;
+    }
+
+    public void setFirstName(String firstName) {
+        this.firstName = firstName;
+    }
+
+    public String getLastName() {
+        return lastName;
+    }
+
+    public void setLastName(String lastName) {
+        this.lastName = lastName;
+    }
+
+    public String getEmail() {
+        return email;
+    }
+
+    public void setEmail(String email) {
+        this.email = email;
+    }
+
+    public String getImageUrl() {
+        return imageUrl;
+    }
+
+    public void setImageUrl(String imageUrl) {
+        this.imageUrl = imageUrl;
+    }
+
+    public boolean getActivated() {
+        return activated;
+    }
+
+    public void setActivated(boolean activated) {
+        this.activated = activated;
+    }
+
+    public String getActivationKey() {
+        return activationKey;
+    }
+
+    public void setActivationKey(String activationKey) {
+        this.activationKey = activationKey;
+    }
+
+    public String getResetKey() {
+        return resetKey;
+    }
+
+    public void setResetKey(String resetKey) {
+        this.resetKey = resetKey;
+    }
+
+    public Instant getResetDate() {
+        return resetDate;
+    }
+
+    public void setResetDate(Instant resetDate) {
+        this.resetDate = resetDate;
+    }
+
+    public String getLangKey() {
+        return langKey;
+    }
+
+    public void setLangKey(String langKey) {
+        this.langKey = langKey;
+    }
+
+    public Set<Authority> getAuthorities() {
+        return authorities;
+    }
+
+    public void setAuthorities(Set<Authority> authorities) {
+        this.authorities = authorities;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) {
+            return true;
+        }
+        if (o == null || getClass() != o.getClass()) {
+            return false;
+        }
+
+        User user = (User) o;
+        return !(user.getId() == null || getId() == null) && Objects.equals(getId(), user.getId());
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hashCode(getId());
+    }
+
+    @Override
+    public String toString() {
+        return "User{" +
+            "login='" + login + '\'' +
+            ", firstName='" + firstName + '\'' +
+            ", lastName='" + lastName + '\'' +
+            ", email='" + email + '\'' +
+            ", imageUrl='" + imageUrl + '\'' +
+            ", activated='" + activated + '\'' +
+            ", langKey='" + langKey + '\'' +
+            ", activationKey='" + activationKey + '\'' +
+            "}";
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/domain/package-info.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/domain/package-info.java
@ -0,0 +1,4 @@
+/**
+ * JPA domain objects.
+ */
+package com.baeldung.jhipster6.domain;
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/repository/AuthorityRepository.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/repository/AuthorityRepository.java
@ -0,0 +1,11 @@
+package com.baeldung.jhipster6.repository;
+
+import com.baeldung.jhipster6.domain.Authority;
+
+import org.springframework.data.jpa.repository.JpaRepository;
+
+/**
+ * Spring Data JPA repository for the Authority entity.
+ */
+public interface AuthorityRepository extends JpaRepository<Authority, String> {
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/repository/BookRepository.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/repository/BookRepository.java
@ -0,0 +1,15 @@
+package com.baeldung.jhipster6.repository;
+
+import com.baeldung.jhipster6.domain.Book;
+import org.springframework.data.jpa.repository.*;
+import org.springframework.stereotype.Repository;
+
+
+/**
+ * Spring Data  repository for the Book entity.
+ */
+@SuppressWarnings("unused")
+@Repository
+public interface BookRepository extends JpaRepository<Book, Long> {
+
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/repository/CustomAuditEventRepository.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/repository/CustomAuditEventRepository.java
@ -0,0 +1,89 @@
+package com.baeldung.jhipster6.repository;
+
+import com.baeldung.jhipster6.config.Constants;
+import com.baeldung.jhipster6.config.audit.AuditEventConverter;
+import com.baeldung.jhipster6.domain.PersistentAuditEvent;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.boot.actuate.audit.AuditEvent;
+import org.springframework.boot.actuate.audit.AuditEventRepository;
+import org.springframework.stereotype.Repository;
+import org.springframework.transaction.annotation.Propagation;
+import org.springframework.transaction.annotation.Transactional;
+
+import java.time.Instant;
+import java.util.*;
+
+/**
+ * An implementation of Spring Boot's AuditEventRepository.
+ */
+@Repository
+public class CustomAuditEventRepository implements AuditEventRepository {
+
+    private static final String AUTHORIZATION_FAILURE = "AUTHORIZATION_FAILURE";
+
+    /**
+     * Should be the same as in Liquibase migration.
+     */
+    protected static final int EVENT_DATA_COLUMN_MAX_LENGTH = 255;
+
+    private final PersistenceAuditEventRepository persistenceAuditEventRepository;
+
+    private final AuditEventConverter auditEventConverter;
+
+    private final Logger log = LoggerFactory.getLogger(getClass());
+
+    public CustomAuditEventRepository(PersistenceAuditEventRepository persistenceAuditEventRepository,
+            AuditEventConverter auditEventConverter) {
+
+        this.persistenceAuditEventRepository = persistenceAuditEventRepository;
+        this.auditEventConverter = auditEventConverter;
+    }
+
+    @Override
+    public List<AuditEvent> find(String principal, Instant after, String type) {
+        Iterable<PersistentAuditEvent> persistentAuditEvents =
+            persistenceAuditEventRepository.findByPrincipalAndAuditEventDateAfterAndAuditEventType(principal, after, type);
+        return auditEventConverter.convertToAuditEvent(persistentAuditEvents);
+    }
+
+    @Override
+    @Transactional(propagation = Propagation.REQUIRES_NEW)
+    public void add(AuditEvent event) {
+        if (!AUTHORIZATION_FAILURE.equals(event.getType()) &&
+            !Constants.ANONYMOUS_USER.equals(event.getPrincipal())) {
+
+            PersistentAuditEvent persistentAuditEvent = new PersistentAuditEvent();
+            persistentAuditEvent.setPrincipal(event.getPrincipal());
+            persistentAuditEvent.setAuditEventType(event.getType());
+            persistentAuditEvent.setAuditEventDate(event.getTimestamp());
+            Map<String, String> eventData = auditEventConverter.convertDataToStrings(event.getData());
+            persistentAuditEvent.setData(truncate(eventData));
+            persistenceAuditEventRepository.save(persistentAuditEvent);
+        }
+    }
+
+    /**
+     * Truncate event data that might exceed column length.
+     */
+    private Map<String, String> truncate(Map<String, String> data) {
+        Map<String, String> results = new HashMap<>();
+
+        if (data != null) {
+            for (Map.Entry<String, String> entry : data.entrySet()) {
+                String value = entry.getValue();
+                if (value != null) {
+                    int length = value.length();
+                    if (length > EVENT_DATA_COLUMN_MAX_LENGTH) {
+                        value = value.substring(0, EVENT_DATA_COLUMN_MAX_LENGTH);
+                        log.warn("Event data for {} too long ({}) has been truncated to {}. Consider increasing column width.",
+                                 entry.getKey(), length, EVENT_DATA_COLUMN_MAX_LENGTH);
+                    }
+                }
+                results.put(entry.getKey(), value);
+            }
+        }
+        return results;
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/repository/PersistenceAuditEventRepository.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/repository/PersistenceAuditEventRepository.java
@ -0,0 +1,25 @@
+package com.baeldung.jhipster6.repository;
+
+import com.baeldung.jhipster6.domain.PersistentAuditEvent;
+import org.springframework.data.domain.Page;
+import org.springframework.data.domain.Pageable;
+import org.springframework.data.jpa.repository.JpaRepository;
+
+import java.time.Instant;
+import java.util.List;
+
+/**
+ * Spring Data JPA repository for the PersistentAuditEvent entity.
+ */
+public interface PersistenceAuditEventRepository extends JpaRepository<PersistentAuditEvent, Long> {
+
+    List<PersistentAuditEvent> findByPrincipal(String principal);
+
+    List<PersistentAuditEvent> findByAuditEventDateAfter(Instant after);
+
+    List<PersistentAuditEvent> findByPrincipalAndAuditEventDateAfter(String principal, Instant after);
+
+    List<PersistentAuditEvent> findByPrincipalAndAuditEventDateAfterAndAuditEventType(String principal, Instant after, String type);
+
+    Page<PersistentAuditEvent> findAllByAuditEventDateBetween(Instant fromDate, Instant toDate, Pageable pageable);
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/repository/UserRepository.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/repository/UserRepository.java
@ -0,0 +1,40 @@
+package com.baeldung.jhipster6.repository;
+
+import com.baeldung.jhipster6.domain.User;
+
+import org.springframework.data.domain.Page;
+import org.springframework.data.domain.Pageable;
+import org.springframework.data.jpa.repository.EntityGraph;
+import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.stereotype.Repository;
+import java.util.List;
+import java.util.Optional;
+import java.time.Instant;
+
+/**
+ * Spring Data JPA repository for the User entity.
+ */
+@Repository
+public interface UserRepository extends JpaRepository<User, Long> {
+
+    Optional<User> findOneByActivationKey(String activationKey);
+
+    List<User> findAllByActivatedIsFalseAndCreatedDateBefore(Instant dateTime);
+
+    Optional<User> findOneByResetKey(String resetKey);
+
+    Optional<User> findOneByEmailIgnoreCase(String email);
+
+    Optional<User> findOneByLogin(String login);
+
+    @EntityGraph(attributePaths = "authorities")
+    Optional<User> findOneWithAuthoritiesById(Long id);
+
+    @EntityGraph(attributePaths = "authorities")
+    Optional<User> findOneWithAuthoritiesByLogin(String login);
+
+    @EntityGraph(attributePaths = "authorities")
+    Optional<User> findOneWithAuthoritiesByEmail(String email);
+
+    Page<User> findAllByLoginNot(Pageable pageable, String login);
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/repository/package-info.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/repository/package-info.java
@ -0,0 +1,4 @@
+/**
+ * Spring Data JPA repositories.
+ */
+package com.baeldung.jhipster6.repository;
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/security/AuthoritiesConstants.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/security/AuthoritiesConstants.java
@ -0,0 +1,16 @@
+package com.baeldung.jhipster6.security;
+
+/**
+ * Constants for Spring Security authorities.
+ */
+public final class AuthoritiesConstants {
+
+    public static final String ADMIN = "ROLE_ADMIN";
+
+    public static final String USER = "ROLE_USER";
+
+    public static final String ANONYMOUS = "ROLE_ANONYMOUS";
+
+    private AuthoritiesConstants() {
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/security/CustomAuthenticationManager.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/security/CustomAuthenticationManager.java
@ -0,0 +1,126 @@
+package com.baeldung.jhipster6.security;
+
+import com.baeldung.jhipster6.domain.User;
+import com.baeldung.jhipster6.security.dto.LoginRequest;
+import com.baeldung.jhipster6.security.dto.LoginResponse;
+import com.baeldung.jhipster6.service.UserService;
+import com.baeldung.jhipster6.service.dto.UserDTO;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.http.ResponseEntity;
+import org.springframework.security.authentication.AuthenticationManager;
+import org.springframework.security.authentication.AuthenticationServiceException;
+import org.springframework.security.authentication.BadCredentialsException;
+import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
+import org.springframework.security.core.Authentication;
+import org.springframework.security.core.AuthenticationException;
+import org.springframework.security.core.GrantedAuthority;
+import org.springframework.security.core.authority.SimpleGrantedAuthority;
+import org.springframework.stereotype.Component;
+import org.springframework.web.client.RestTemplate;
+
+import java.util.Collection;
+import java.util.Collections;
+import java.util.stream.Collectors;
+
+@Component
+public class CustomAuthenticationManager implements AuthenticationManager {
+
+    private final static Logger LOG = LoggerFactory.getLogger(CustomAuthenticationManager.class);
+
+    private final String REMOTE_LOGIN_URL = "https://example.com/login";
+
+    private final RestTemplate restTemplate = new RestTemplate();
+
+    @Autowired
+    private UserService userService;
+
+    @Override
+    public Authentication authenticate(Authentication authentication) throws AuthenticationException {
+
+        LoginRequest loginRequest = new LoginRequest();
+        loginRequest.setUsername(authentication.getPrincipal().toString());
+        loginRequest.setPassword(authentication.getCredentials().toString());
+
+        try
+        {
+            ResponseEntity<LoginResponse> response =
+                restTemplate.postForEntity(
+                    REMOTE_LOGIN_URL,
+                    loginRequest,
+                    LoginResponse.class);
+
+            if(response.getStatusCode().is2xxSuccessful())
+            {
+                //
+                // Need to create a new local user if this is the  first time logging in; this
+                // is required so they can be issued JWTs. We can use this flow to also keep
+                // our local use entry up to date with data from the remote service if needed
+                // (for example, if the first and last name might change, this is where we would
+                // update the local user entry)
+                //
+
+                User user = userService.getUserWithAuthoritiesByLogin(authentication.getPrincipal().toString())
+                                       .orElseGet(() -> userService.createUser(createUserDTO(response.getBody(), authentication)));
+                return createAuthentication(authentication, user);
+            }
+            else
+            {
+                throw new BadCredentialsException("Invalid username or password");
+            }
+        }
+        catch (Exception e)
+        {
+            LOG.warn("Failed to authenticate", e);
+            throw new AuthenticationServiceException("Failed to login", e);
+        }
+    }
+
+    /**
+     * Creates a new authentication with basic roles
+     * @param auth Contains auth details that will be copied into the new one.
+     * @param user User object representing who is logging in
+     * @return Authentication
+     */
+    private Authentication createAuthentication(Authentication auth, User user) {
+
+        //
+        // Honor any roles the user already has set; default is just USER role
+        // but could be modified after account creation
+        //
+
+        Collection<? extends GrantedAuthority> authorities = user
+            .getAuthorities()
+            .stream()
+            .map(a -> new SimpleGrantedAuthority(a.getName()))
+            .collect(Collectors.toSet());
+
+        UsernamePasswordAuthenticationToken token
+            = new UsernamePasswordAuthenticationToken(
+            user.getId(),
+            auth.getCredentials().toString(),
+            authorities);
+
+        return token;
+    }
+
+    /**
+     * Creates a new UserDTO with basic info.
+     * @param loginResponse Response from peloton login API
+     * @param authentication Contains user login info (namely username and password)
+     * @return UserDTO
+     */
+    private UserDTO createUserDTO(LoginResponse loginResponse, Authentication authentication) {
+
+        UserDTO dto = new UserDTO();
+
+        dto.setActivated(true);
+        dto.setEmail(loginResponse.getEmail());
+        dto.setAuthorities(Collections.singleton(AuthoritiesConstants.USER));
+        dto.setFirstName(loginResponse.getFirstName());
+        dto.setLastName(loginResponse.getLastName());
+
+        return dto;
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/security/DomainUserDetailsService.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/security/DomainUserDetailsService.java
@ -0,0 +1,63 @@
+package com.baeldung.jhipster6.security;
+
+import com.baeldung.jhipster6.domain.User;
+import com.baeldung.jhipster6.repository.UserRepository;
+
+import org.hibernate.validator.internal.constraintvalidators.hv.EmailValidator;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.security.core.GrantedAuthority;
+import org.springframework.security.core.authority.SimpleGrantedAuthority;
+import org.springframework.security.core.userdetails.UserDetails;
+import org.springframework.security.core.userdetails.UserDetailsService;
+import org.springframework.security.core.userdetails.UsernameNotFoundException;
+import org.springframework.stereotype.Component;
+import org.springframework.transaction.annotation.Transactional;
+
+import java.util.*;
+import java.util.stream.Collectors;
+
+/**
+ * Authenticate a user from the database.
+ */
+@Component("userDetailsService")
+public class DomainUserDetailsService implements UserDetailsService {
+
+    private final Logger log = LoggerFactory.getLogger(DomainUserDetailsService.class);
+
+    private final UserRepository userRepository;
+
+    public DomainUserDetailsService(UserRepository userRepository) {
+        this.userRepository = userRepository;
+    }
+
+    @Override
+    @Transactional
+    public UserDetails loadUserByUsername(final String login) {
+        log.debug("Authenticating {}", login);
+
+        if (new EmailValidator().isValid(login, null)) {
+            return userRepository.findOneWithAuthoritiesByEmail(login)
+                .map(user -> createSpringSecurityUser(login, user))
+                .orElseThrow(() -> new UsernameNotFoundException("User with email " + login + " was not found in the database"));
+        }
+
+        String lowercaseLogin = login.toLowerCase(Locale.ENGLISH);
+        return userRepository.findOneWithAuthoritiesByLogin(lowercaseLogin)
+            .map(user -> createSpringSecurityUser(lowercaseLogin, user))
+            .orElseThrow(() -> new UsernameNotFoundException("User " + lowercaseLogin + " was not found in the database"));
+
+    }
+
+    private org.springframework.security.core.userdetails.User createSpringSecurityUser(String lowercaseLogin, User user) {
+        if (!user.getActivated()) {
+            throw new UserNotActivatedException("User " + lowercaseLogin + " was not activated");
+        }
+        List<GrantedAuthority> grantedAuthorities = user.getAuthorities().stream()
+            .map(authority -> new SimpleGrantedAuthority(authority.getName()))
+            .collect(Collectors.toList());
+        return new org.springframework.security.core.userdetails.User(user.getLogin(),
+            user.getPassword(),
+            grantedAuthorities);
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/security/SecurityUtils.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/security/SecurityUtils.java
@ -0,0 +1,76 @@
+package com.baeldung.jhipster6.security;
+
+import org.springframework.security.core.context.SecurityContext;
+import org.springframework.security.core.context.SecurityContextHolder;
+import org.springframework.security.core.userdetails.UserDetails;
+
+import java.util.Optional;
+
+/**
+ * Utility class for Spring Security.
+ */
+public final class SecurityUtils {
+
+    private SecurityUtils() {
+    }
+
+    /**
+     * Get the login of the current user.
+     *
+     * @return the login of the current user
+     */
+    public static Optional<String> getCurrentUserLogin() {
+        SecurityContext securityContext = SecurityContextHolder.getContext();
+        return Optional.ofNullable(securityContext.getAuthentication())
+            .map(authentication -> {
+                if (authentication.getPrincipal() instanceof UserDetails) {
+                    UserDetails springSecurityUser = (UserDetails) authentication.getPrincipal();
+                    return springSecurityUser.getUsername();
+                } else if (authentication.getPrincipal() instanceof String) {
+                    return (String) authentication.getPrincipal();
+                }
+                return null;
+            });
+    }
+
+    /**
+     * Get the JWT of the current user.
+     *
+     * @return the JWT of the current user
+     */
+    public static Optional<String> getCurrentUserJWT() {
+        SecurityContext securityContext = SecurityContextHolder.getContext();
+        return Optional.ofNullable(securityContext.getAuthentication())
+            .filter(authentication -> authentication.getCredentials() instanceof String)
+            .map(authentication -> (String) authentication.getCredentials());
+    }
+
+    /**
+     * Check if a user is authenticated.
+     *
+     * @return true if the user is authenticated, false otherwise
+     */
+    public static boolean isAuthenticated() {
+        SecurityContext securityContext = SecurityContextHolder.getContext();
+        return Optional.ofNullable(securityContext.getAuthentication())
+            .map(authentication -> authentication.getAuthorities().stream()
+                .noneMatch(grantedAuthority -> grantedAuthority.getAuthority().equals(AuthoritiesConstants.ANONYMOUS)))
+            .orElse(false);
+    }
+
+    /**
+     * If the current user has a specific authority (security role).
+     * <p>
+     * The name of this method comes from the isUserInRole() method in the Servlet API
+     *
+     * @param authority the authority to check
+     * @return true if the current user has the authority, false otherwise
+     */
+    public static boolean isCurrentUserInRole(String authority) {
+        SecurityContext securityContext = SecurityContextHolder.getContext();
+        return Optional.ofNullable(securityContext.getAuthentication())
+            .map(authentication -> authentication.getAuthorities().stream()
+                .anyMatch(grantedAuthority -> grantedAuthority.getAuthority().equals(authority)))
+            .orElse(false);
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/security/SpringSecurityAuditorAware.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/security/SpringSecurityAuditorAware.java
@ -0,0 +1,20 @@
+package com.baeldung.jhipster6.security;
+
+import com.baeldung.jhipster6.config.Constants;
+
+import java.util.Optional;
+
+import org.springframework.data.domain.AuditorAware;
+import org.springframework.stereotype.Component;
+
+/**
+ * Implementation of AuditorAware based on Spring Security.
+ */
+@Component
+public class SpringSecurityAuditorAware implements AuditorAware<String> {
+
+    @Override
+    public Optional<String> getCurrentAuditor() {
+        return Optional.of(SecurityUtils.getCurrentUserLogin().orElse(Constants.SYSTEM_ACCOUNT));
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/security/UserNotActivatedException.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/security/UserNotActivatedException.java
@ -0,0 +1,19 @@
+package com.baeldung.jhipster6.security;
+
+import org.springframework.security.core.AuthenticationException;
+
+/**
+ * This exception is thrown in case of a not activated user trying to authenticate.
+ */
+public class UserNotActivatedException extends AuthenticationException {
+
+    private static final long serialVersionUID = 1L;
+
+    public UserNotActivatedException(String message) {
+        super(message);
+    }
+
+    public UserNotActivatedException(String message, Throwable t) {
+        super(message, t);
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/security/dto/LoginRequest.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/security/dto/LoginRequest.java
@ -0,0 +1,30 @@
+package com.baeldung.jhipster6.security.dto;
+
+/**
+ * Simple DTO representing a login request to a remote service.
+ */
+public class LoginRequest {
+
+    private String username;
+
+    private String password;
+
+    public LoginRequest() {
+    }
+
+    public String getUsername() {
+        return username;
+    }
+
+    public void setUsername(String username) {
+        this.username = username;
+    }
+
+    public String getPassword() {
+        return password;
+    }
+
+    public void setPassword(String password) {
+        this.password = password;
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/security/dto/LoginResponse.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/security/dto/LoginResponse.java
@ -0,0 +1,50 @@
+package com.baeldung.jhipster6.security.dto;
+
+/**
+ * Simple DTO representing the response of logging in using a remote service.
+ */
+public class LoginResponse {
+
+    private String username;
+
+    private String firstName;
+
+    private String lastName;
+
+    private String email;
+
+    public LoginResponse() {
+    }
+
+    public String getUsername() {
+        return username;
+    }
+
+    public void setUsername(String username) {
+        this.username = username;
+    }
+
+    public String getFirstName() {
+        return firstName;
+    }
+
+    public void setFirstName(String firstName) {
+        this.firstName = firstName;
+    }
+
+    public String getLastName() {
+        return lastName;
+    }
+
+    public void setLastName(String lastName) {
+        this.lastName = lastName;
+    }
+
+    public String getEmail() {
+        return email;
+    }
+
+    public void setEmail(String email) {
+        this.email = email;
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/security/jwt/JWTConfigurer.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/security/jwt/JWTConfigurer.java
@ -0,0 +1,21 @@
+package com.baeldung.jhipster6.security.jwt;
+
+import org.springframework.security.config.annotation.SecurityConfigurerAdapter;
+import org.springframework.security.config.annotation.web.builders.HttpSecurity;
+import org.springframework.security.web.DefaultSecurityFilterChain;
+import org.springframework.security.web.authentication.UsernamePasswordAuthenticationFilter;
+
+public class JWTConfigurer extends SecurityConfigurerAdapter<DefaultSecurityFilterChain, HttpSecurity> {
+
+    private TokenProvider tokenProvider;
+
+    public JWTConfigurer(TokenProvider tokenProvider) {
+        this.tokenProvider = tokenProvider;
+    }
+
+    @Override
+    public void configure(HttpSecurity http) throws Exception {
+        JWTFilter customFilter = new JWTFilter(tokenProvider);
+        http.addFilterBefore(customFilter, UsernamePasswordAuthenticationFilter.class);
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/security/jwt/JWTFilter.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/security/jwt/JWTFilter.java
@ -0,0 +1,48 @@
+package com.baeldung.jhipster6.security.jwt;
+
+import org.springframework.security.core.Authentication;
+import org.springframework.security.core.context.SecurityContextHolder;
+import org.springframework.util.StringUtils;
+import org.springframework.web.filter.GenericFilterBean;
+
+import javax.servlet.FilterChain;
+import javax.servlet.ServletException;
+import javax.servlet.ServletRequest;
+import javax.servlet.ServletResponse;
+import javax.servlet.http.HttpServletRequest;
+import java.io.IOException;
+
+/**
+ * Filters incoming requests and installs a Spring Security principal if a header corresponding to a valid user is
+ * found.
+ */
+public class JWTFilter extends GenericFilterBean {
+
+    public static final String AUTHORIZATION_HEADER = "Authorization";
+
+    private TokenProvider tokenProvider;
+
+    public JWTFilter(TokenProvider tokenProvider) {
+        this.tokenProvider = tokenProvider;
+    }
+
+    @Override
+    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain)
+        throws IOException, ServletException {
+        HttpServletRequest httpServletRequest = (HttpServletRequest) servletRequest;
+        String jwt = resolveToken(httpServletRequest);
+        if (StringUtils.hasText(jwt) && this.tokenProvider.validateToken(jwt)) {
+            Authentication authentication = this.tokenProvider.getAuthentication(jwt);
+            SecurityContextHolder.getContext().setAuthentication(authentication);
+        }
+        filterChain.doFilter(servletRequest, servletResponse);
+    }
+
+    private String resolveToken(HttpServletRequest request){
+        String bearerToken = request.getHeader(AUTHORIZATION_HEADER);
+        if (StringUtils.hasText(bearerToken) && bearerToken.startsWith("Bearer ")) {
+            return bearerToken.substring(7);
+        }
+        return null;
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/security/jwt/TokenProvider.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/security/jwt/TokenProvider.java
@ -0,0 +1,119 @@
+package com.baeldung.jhipster6.security.jwt;
+
+import java.nio.charset.StandardCharsets;
+import java.security.Key;
+import java.util.*;
+import java.util.stream.Collectors;
+import javax.annotation.PostConstruct;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
+import org.springframework.security.core.Authentication;
+import org.springframework.security.core.GrantedAuthority;
+import org.springframework.security.core.authority.SimpleGrantedAuthority;
+import org.springframework.security.core.userdetails.User;
+import org.springframework.stereotype.Component;
+import org.springframework.util.StringUtils;
+
+import io.github.jhipster.config.JHipsterProperties;
+import io.jsonwebtoken.*;
+import io.jsonwebtoken.io.Decoders;
+import io.jsonwebtoken.security.Keys;
+
+@Component
+public class TokenProvider {
+
+    private final Logger log = LoggerFactory.getLogger(TokenProvider.class);
+
+    private static final String AUTHORITIES_KEY = "auth";
+
+    private Key key;
+
+    private long tokenValidityInMilliseconds;
+
+    private long tokenValidityInMillisecondsForRememberMe;
+
+    private final JHipsterProperties jHipsterProperties;
+
+    public TokenProvider(JHipsterProperties jHipsterProperties) {
+        this.jHipsterProperties = jHipsterProperties;
+    }
+
+    @PostConstruct
+    public void init() {
+        byte[] keyBytes;
+        String secret = jHipsterProperties.getSecurity().getAuthentication().getJwt().getSecret();
+        if (!StringUtils.isEmpty(secret)) {
+            log.warn("Warning: the JWT key used is not Base64-encoded. " +
+                "We recommend using the `jhipster.security.authentication.jwt.base64-secret` key for optimum security.");
+            keyBytes = secret.getBytes(StandardCharsets.UTF_8);
+        } else {
+            log.debug("Using a Base64-encoded JWT secret key");
+            keyBytes = Decoders.BASE64.decode(jHipsterProperties.getSecurity().getAuthentication().getJwt().getBase64Secret());
+        }
+        this.key = Keys.hmacShaKeyFor(keyBytes);
+        this.tokenValidityInMilliseconds =
+            1000 * jHipsterProperties.getSecurity().getAuthentication().getJwt().getTokenValidityInSeconds();
+        this.tokenValidityInMillisecondsForRememberMe =
+            1000 * jHipsterProperties.getSecurity().getAuthentication().getJwt()
+                .getTokenValidityInSecondsForRememberMe();
+    }
+
+    public String createToken(Authentication authentication, boolean rememberMe) {
+        String authorities = authentication.getAuthorities().stream()
+            .map(GrantedAuthority::getAuthority)
+            .collect(Collectors.joining(","));
+
+        long now = (new Date()).getTime();
+        Date validity;
+        if (rememberMe) {
+            validity = new Date(now + this.tokenValidityInMillisecondsForRememberMe);
+        } else {
+            validity = new Date(now + this.tokenValidityInMilliseconds);
+        }
+
+        return Jwts.builder()
+            .setSubject(authentication.getName())
+            .claim(AUTHORITIES_KEY, authorities)
+            .signWith(key, SignatureAlgorithm.HS512)
+            .setExpiration(validity)
+            .compact();
+    }
+
+    public Authentication getAuthentication(String token) {
+        Claims claims = Jwts.parser()
+            .setSigningKey(key)
+            .parseClaimsJws(token)
+            .getBody();
+
+        Collection<? extends GrantedAuthority> authorities =
+            Arrays.stream(claims.get(AUTHORITIES_KEY).toString().split(","))
+                .map(SimpleGrantedAuthority::new)
+                .collect(Collectors.toList());
+
+        User principal = new User(claims.getSubject(), "", authorities);
+
+        return new UsernamePasswordAuthenticationToken(principal, token, authorities);
+    }
+
+    public boolean validateToken(String authToken) {
+        try {
+            Jwts.parser().setSigningKey(key).parseClaimsJws(authToken);
+            return true;
+        } catch (io.jsonwebtoken.security.SecurityException | MalformedJwtException e) {
+            log.info("Invalid JWT signature.");
+            log.trace("Invalid JWT signature trace: {}", e);
+        } catch (ExpiredJwtException e) {
+            log.info("Expired JWT token.");
+            log.trace("Expired JWT token trace: {}", e);
+        } catch (UnsupportedJwtException e) {
+            log.info("Unsupported JWT token.");
+            log.trace("Unsupported JWT token trace: {}", e);
+        } catch (IllegalArgumentException e) {
+            log.info("JWT token compact of handler are invalid.");
+            log.trace("JWT token compact of handler are invalid trace: {}", e);
+        }
+        return false;
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/security/package-info.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/security/package-info.java
@ -0,0 +1,4 @@
+/**
+ * Spring Security configuration.
+ */
+package com.baeldung.jhipster6.security;
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/service/AuditEventService.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/service/AuditEventService.java
@ -0,0 +1,52 @@
+package com.baeldung.jhipster6.service;
+
+import com.baeldung.jhipster6.config.audit.AuditEventConverter;
+import com.baeldung.jhipster6.repository.PersistenceAuditEventRepository;
+
+import org.springframework.boot.actuate.audit.AuditEvent;
+import org.springframework.data.domain.Page;
+import org.springframework.data.domain.Pageable;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+
+import java.time.Instant;
+import java.util.Optional;
+
+/**
+ * Service for managing audit events.
+ * <p>
+ * This is the default implementation to support SpringBoot Actuator AuditEventRepository
+ */
+@Service
+@Transactional
+public class AuditEventService {
+
+    private final PersistenceAuditEventRepository persistenceAuditEventRepository;
+
+    private final AuditEventConverter auditEventConverter;
+
+    public AuditEventService(
+        PersistenceAuditEventRepository persistenceAuditEventRepository,
+        AuditEventConverter auditEventConverter) {
+
+        this.persistenceAuditEventRepository = persistenceAuditEventRepository;
+        this.auditEventConverter = auditEventConverter;
+    }
+
+    public Page<AuditEvent> findAll(Pageable pageable) {
+        return persistenceAuditEventRepository.findAll(pageable)
+            .map(auditEventConverter::convertToAuditEvent);
+    }
+
+    public Page<AuditEvent> findByDates(Instant fromDate, Instant toDate, Pageable pageable) {
+        return persistenceAuditEventRepository.findAllByAuditEventDateBetween(fromDate, toDate, pageable)
+            .map(auditEventConverter::convertToAuditEvent);
+    }
+
+    public Optional<AuditEvent> find(Long id) {
+        return Optional.ofNullable(persistenceAuditEventRepository.findById(id))
+            .filter(Optional::isPresent)
+            .map(Optional::get)
+            .map(auditEventConverter::convertToAuditEvent);
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/service/BookService.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/service/BookService.java
@ -0,0 +1,50 @@
+package com.baeldung.jhipster6.service;
+
+import com.baeldung.jhipster6.service.dto.BookDTO;
+
+import java.util.List;
+import java.util.Optional;
+
+/**
+ * Service Interface for managing Book.
+ */
+public interface BookService {
+
+    /**
+     * Save a book.
+     *
+     * @param bookDTO the entity to save
+     * @return the persisted entity
+     */
+    BookDTO save(BookDTO bookDTO);
+
+    /**
+     * Get all the books.
+     *
+     * @return the list of entities
+     */
+    List<BookDTO> findAll();
+
+
+    /**
+     * Get the "id" book.
+     *
+     * @param id the id of the entity
+     * @return the entity
+     */
+    Optional<BookDTO> findOne(Long id);
+
+    /**
+     * Delete the "id" book.
+     *
+     * @param id the id of the entity
+     */
+    void delete(Long id);
+
+    /**
+     * Simulates purchasing a book by reducing the stock of a book by 1.
+     * @param id the id of the book
+     * @return Updated BookDTO, empty if not found, or throws exception if an error occurs.
+     */
+    Optional<BookDTO> purchase(Long id);
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/service/MailService.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/service/MailService.java
@ -0,0 +1,105 @@
+package com.baeldung.jhipster6.service;
+
+import com.baeldung.jhipster6.domain.User;
+
+import io.github.jhipster.config.JHipsterProperties;
+
+import java.nio.charset.StandardCharsets;
+import java.util.Locale;
+import javax.mail.internet.MimeMessage;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.context.MessageSource;
+import org.springframework.mail.javamail.JavaMailSender;
+import org.springframework.mail.javamail.MimeMessageHelper;
+import org.springframework.scheduling.annotation.Async;
+import org.springframework.stereotype.Service;
+import org.thymeleaf.context.Context;
+import org.thymeleaf.spring5.SpringTemplateEngine;
+
+/**
+ * Service for sending emails.
+ * <p>
+ * We use the @Async annotation to send emails asynchronously.
+ */
+@Service
+public class MailService {
+
+    private final Logger log = LoggerFactory.getLogger(MailService.class);
+
+    private static final String USER = "user";
+
+    private static final String BASE_URL = "baseUrl";
+
+    private final JHipsterProperties jHipsterProperties;
+
+    private final JavaMailSender javaMailSender;
+
+    private final MessageSource messageSource;
+
+    private final SpringTemplateEngine templateEngine;
+
+    public MailService(JHipsterProperties jHipsterProperties, JavaMailSender javaMailSender,
+            MessageSource messageSource, SpringTemplateEngine templateEngine) {
+
+        this.jHipsterProperties = jHipsterProperties;
+        this.javaMailSender = javaMailSender;
+        this.messageSource = messageSource;
+        this.templateEngine = templateEngine;
+    }
+
+    @Async
+    public void sendEmail(String to, String subject, String content, boolean isMultipart, boolean isHtml) {
+        log.debug("Send email[multipart '{}' and html '{}'] to '{}' with subject '{}' and content={}",
+            isMultipart, isHtml, to, subject, content);
+
+        // Prepare message using a Spring helper
+        MimeMessage mimeMessage = javaMailSender.createMimeMessage();
+        try {
+            MimeMessageHelper message = new MimeMessageHelper(mimeMessage, isMultipart, StandardCharsets.UTF_8.name());
+            message.setTo(to);
+            message.setFrom(jHipsterProperties.getMail().getFrom());
+            message.setSubject(subject);
+            message.setText(content, isHtml);
+            javaMailSender.send(mimeMessage);
+            log.debug("Sent email to User '{}'", to);
+        } catch (Exception e) {
+            if (log.isDebugEnabled()) {
+                log.warn("Email could not be sent to user '{}'", to, e);
+            } else {
+                log.warn("Email could not be sent to user '{}': {}", to, e.getMessage());
+            }
+        }
+    }
+
+    @Async
+    public void sendEmailFromTemplate(User user, String templateName, String titleKey) {
+        Locale locale = Locale.forLanguageTag(user.getLangKey());
+        Context context = new Context(locale);
+        context.setVariable(USER, user);
+        context.setVariable(BASE_URL, jHipsterProperties.getMail().getBaseUrl());
+        String content = templateEngine.process(templateName, context);
+        String subject = messageSource.getMessage(titleKey, null, locale);
+        sendEmail(user.getEmail(), subject, content, false, true);
+
+    }
+
+    @Async
+    public void sendActivationEmail(User user) {
+        log.debug("Sending activation email to '{}'", user.getEmail());
+        sendEmailFromTemplate(user, "mail/activationEmail", "email.activation.title");
+    }
+
+    @Async
+    public void sendCreationEmail(User user) {
+        log.debug("Sending creation email to '{}'", user.getEmail());
+        sendEmailFromTemplate(user, "mail/creationEmail", "email.activation.title");
+    }
+
+    @Async
+    public void sendPasswordResetMail(User user) {
+        log.debug("Sending password reset email to '{}'", user.getEmail());
+        sendEmailFromTemplate(user, "mail/passwordResetEmail", "email.reset.title");
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/service/UserService.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/service/UserService.java
@ -0,0 +1,276 @@
+package com.baeldung.jhipster6.service;
+
+import com.baeldung.jhipster6.config.Constants;
+import com.baeldung.jhipster6.domain.Authority;
+import com.baeldung.jhipster6.domain.User;
+import com.baeldung.jhipster6.repository.AuthorityRepository;
+import com.baeldung.jhipster6.repository.UserRepository;
+import com.baeldung.jhipster6.security.AuthoritiesConstants;
+import com.baeldung.jhipster6.security.SecurityUtils;
+import com.baeldung.jhipster6.service.dto.UserDTO;
+import com.baeldung.jhipster6.service.util.RandomUtil;
+import com.baeldung.jhipster6.web.rest.errors.*;
+import com.baeldung.jhipster6.web.rest.errors.EmailAlreadyUsedException;
+import com.baeldung.jhipster6.web.rest.errors.InvalidPasswordException;
+import com.baeldung.jhipster6.web.rest.errors.LoginAlreadyUsedException;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.data.domain.Page;
+import org.springframework.data.domain.Pageable;
+import org.springframework.scheduling.annotation.Scheduled;
+import org.springframework.security.crypto.password.PasswordEncoder;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+
+import java.time.Instant;
+import java.time.temporal.ChronoUnit;
+import java.util.*;
+import java.util.stream.Collectors;
+
+/**
+ * Service class for managing users.
+ */
+@Service
+@Transactional
+public class UserService {
+
+    private final Logger log = LoggerFactory.getLogger(UserService.class);
+
+    private final UserRepository userRepository;
+
+    private final PasswordEncoder passwordEncoder;
+
+    private final AuthorityRepository authorityRepository;
+
+    public UserService(UserRepository userRepository, PasswordEncoder passwordEncoder, AuthorityRepository authorityRepository) {
+        this.userRepository = userRepository;
+        this.passwordEncoder = passwordEncoder;
+        this.authorityRepository = authorityRepository;
+    }
+
+    public Optional<User> activateRegistration(String key) {
+        log.debug("Activating user for activation key {}", key);
+        return userRepository.findOneByActivationKey(key)
+            .map(user -> {
+                // activate given user for the registration key.
+                user.setActivated(true);
+                user.setActivationKey(null);
+                log.debug("Activated user: {}", user);
+                return user;
+            });
+    }
+
+    public Optional<User> completePasswordReset(String newPassword, String key) {
+        log.debug("Reset user password for reset key {}", key);
+        return userRepository.findOneByResetKey(key)
+            .filter(user -> user.getResetDate().isAfter(Instant.now().minusSeconds(86400)))
+            .map(user -> {
+                user.setPassword(passwordEncoder.encode(newPassword));
+                user.setResetKey(null);
+                user.setResetDate(null);
+                return user;
+            });
+    }
+
+    public Optional<User> requestPasswordReset(String mail) {
+        return userRepository.findOneByEmailIgnoreCase(mail)
+            .filter(User::getActivated)
+            .map(user -> {
+                user.setResetKey(RandomUtil.generateResetKey());
+                user.setResetDate(Instant.now());
+                return user;
+            });
+    }
+
+    public User registerUser(UserDTO userDTO, String password) {
+        userRepository.findOneByLogin(userDTO.getLogin().toLowerCase()).ifPresent(existingUser -> {
+            boolean removed = removeNonActivatedUser(existingUser);
+            if (!removed) {
+                throw new LoginAlreadyUsedException();
+            }
+        });
+        userRepository.findOneByEmailIgnoreCase(userDTO.getEmail()).ifPresent(existingUser -> {
+            boolean removed = removeNonActivatedUser(existingUser);
+            if (!removed) {
+                throw new EmailAlreadyUsedException();
+            }
+        });
+        User newUser = new User();
+        String encryptedPassword = passwordEncoder.encode(password);
+        newUser.setLogin(userDTO.getLogin().toLowerCase());
+        // new user gets initially a generated password
+        newUser.setPassword(encryptedPassword);
+        newUser.setFirstName(userDTO.getFirstName());
+        newUser.setLastName(userDTO.getLastName());
+        newUser.setEmail(userDTO.getEmail().toLowerCase());
+        newUser.setImageUrl(userDTO.getImageUrl());
+        newUser.setLangKey(userDTO.getLangKey());
+        // new user is not active
+        newUser.setActivated(false);
+        // new user gets registration key
+        newUser.setActivationKey(RandomUtil.generateActivationKey());
+        Set<Authority> authorities = new HashSet<>();
+        authorityRepository.findById(AuthoritiesConstants.USER).ifPresent(authorities::add);
+        newUser.setAuthorities(authorities);
+        userRepository.save(newUser);
+        log.debug("Created Information for User: {}", newUser);
+        return newUser;
+    }
+
+    private boolean removeNonActivatedUser(User existingUser){
+        if (existingUser.getActivated()) {
+             return false;
+        }
+        userRepository.delete(existingUser);
+        userRepository.flush();
+        return true;
+    }
+
+    public User createUser(UserDTO userDTO) {
+        User user = new User();
+        user.setLogin(userDTO.getLogin().toLowerCase());
+        user.setFirstName(userDTO.getFirstName());
+        user.setLastName(userDTO.getLastName());
+        user.setEmail(userDTO.getEmail().toLowerCase());
+        user.setImageUrl(userDTO.getImageUrl());
+        if (userDTO.getLangKey() == null) {
+            user.setLangKey(Constants.DEFAULT_LANGUAGE); // default language
+        } else {
+            user.setLangKey(userDTO.getLangKey());
+        }
+        String encryptedPassword = passwordEncoder.encode(RandomUtil.generatePassword());
+        user.setPassword(encryptedPassword);
+        user.setResetKey(RandomUtil.generateResetKey());
+        user.setResetDate(Instant.now());
+        user.setActivated(true);
+        if (userDTO.getAuthorities() != null) {
+            Set<Authority> authorities = userDTO.getAuthorities().stream()
+                .map(authorityRepository::findById)
+                .filter(Optional::isPresent)
+                .map(Optional::get)
+                .collect(Collectors.toSet());
+            user.setAuthorities(authorities);
+        }
+        userRepository.save(user);
+        log.debug("Created Information for User: {}", user);
+        return user;
+    }
+
+    /**
+     * Update basic information (first name, last name, email, language) for the current user.
+     *
+     * @param firstName first name of user
+     * @param lastName last name of user
+     * @param email email id of user
+     * @param langKey language key
+     * @param imageUrl image URL of user
+     */
+    public void updateUser(String firstName, String lastName, String email, String langKey, String imageUrl) {
+        SecurityUtils.getCurrentUserLogin()
+            .flatMap(userRepository::findOneByLogin)
+            .ifPresent(user -> {
+                user.setFirstName(firstName);
+                user.setLastName(lastName);
+                user.setEmail(email.toLowerCase());
+                user.setLangKey(langKey);
+                user.setImageUrl(imageUrl);
+                log.debug("Changed Information for User: {}", user);
+            });
+    }
+
+    /**
+     * Update all information for a specific user, and return the modified user.
+     *
+     * @param userDTO user to update
+     * @return updated user
+     */
+    public Optional<UserDTO> updateUser(UserDTO userDTO) {
+        return Optional.of(userRepository
+            .findById(userDTO.getId()))
+            .filter(Optional::isPresent)
+            .map(Optional::get)
+            .map(user -> {
+                user.setLogin(userDTO.getLogin().toLowerCase());
+                user.setFirstName(userDTO.getFirstName());
+                user.setLastName(userDTO.getLastName());
+                user.setEmail(userDTO.getEmail().toLowerCase());
+                user.setImageUrl(userDTO.getImageUrl());
+                user.setActivated(userDTO.isActivated());
+                user.setLangKey(userDTO.getLangKey());
+                Set<Authority> managedAuthorities = user.getAuthorities();
+                managedAuthorities.clear();
+                userDTO.getAuthorities().stream()
+                    .map(authorityRepository::findById)
+                    .filter(Optional::isPresent)
+                    .map(Optional::get)
+                    .forEach(managedAuthorities::add);
+                log.debug("Changed Information for User: {}", user);
+                return user;
+            })
+            .map(UserDTO::new);
+    }
+
+    public void deleteUser(String login) {
+        userRepository.findOneByLogin(login).ifPresent(user -> {
+            userRepository.delete(user);
+            log.debug("Deleted User: {}", user);
+        });
+    }
+
+    public void changePassword(String currentClearTextPassword, String newPassword) {
+        SecurityUtils.getCurrentUserLogin()
+            .flatMap(userRepository::findOneByLogin)
+            .ifPresent(user -> {
+                String currentEncryptedPassword = user.getPassword();
+                if (!passwordEncoder.matches(currentClearTextPassword, currentEncryptedPassword)) {
+                    throw new InvalidPasswordException();
+                }
+                String encryptedPassword = passwordEncoder.encode(newPassword);
+                user.setPassword(encryptedPassword);
+                log.debug("Changed password for User: {}", user);
+            });
+    }
+
+    @Transactional(readOnly = true)
+    public Page<UserDTO> getAllManagedUsers(Pageable pageable) {
+        return userRepository.findAllByLoginNot(pageable, Constants.ANONYMOUS_USER).map(UserDTO::new);
+    }
+
+    @Transactional(readOnly = true)
+    public Optional<User> getUserWithAuthoritiesByLogin(String login) {
+        return userRepository.findOneWithAuthoritiesByLogin(login);
+    }
+
+    @Transactional(readOnly = true)
+    public Optional<User> getUserWithAuthorities(Long id) {
+        return userRepository.findOneWithAuthoritiesById(id);
+    }
+
+    @Transactional(readOnly = true)
+    public Optional<User> getUserWithAuthorities() {
+        return SecurityUtils.getCurrentUserLogin().flatMap(userRepository::findOneWithAuthoritiesByLogin);
+    }
+
+    /**
+     * Not activated users should be automatically deleted after 3 days.
+     * <p>
+     * This is scheduled to get fired everyday, at 01:00 (am).
+     */
+    @Scheduled(cron = "0 0 1 * * ?")
+    public void removeNotActivatedUsers() {
+        userRepository
+            .findAllByActivatedIsFalseAndCreatedDateBefore(Instant.now().minus(3, ChronoUnit.DAYS))
+            .forEach(user -> {
+                log.debug("Deleting not activated user {}", user.getLogin());
+                userRepository.delete(user);
+            });
+    }
+
+    /**
+     * @return a list of all the authorities
+     */
+    public List<String> getAuthorities() {
+        return authorityRepository.findAll().stream().map(Authority::getName).collect(Collectors.toList());
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/service/dto/BookDTO.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/service/dto/BookDTO.java
@ -0,0 +1,112 @@
+package com.baeldung.jhipster6.service.dto;
+import java.time.LocalDate;
+import javax.validation.constraints.*;
+import java.io.Serializable;
+import java.util.Objects;
+
+/**
+ * A DTO for the Book entity.
+ */
+public class BookDTO implements Serializable {
+
+    private Long id;
+
+    @NotNull
+    private String title;
+
+    @NotNull
+    private String author;
+
+    @NotNull
+    private LocalDate published;
+
+    @NotNull
+    @Min(value = 0)
+    private Integer quantity;
+
+    @NotNull
+    @DecimalMin(value = "0")
+    private Double price;
+
+
+    public Long getId() {
+        return id;
+    }
+
+    public void setId(Long id) {
+        this.id = id;
+    }
+
+    public String getTitle() {
+        return title;
+    }
+
+    public void setTitle(String title) {
+        this.title = title;
+    }
+
+    public String getAuthor() {
+        return author;
+    }
+
+    public void setAuthor(String author) {
+        this.author = author;
+    }
+
+    public LocalDate getPublished() {
+        return published;
+    }
+
+    public void setPublished(LocalDate published) {
+        this.published = published;
+    }
+
+    public Integer getQuantity() {
+        return quantity;
+    }
+
+    public void setQuantity(Integer quantity) {
+        this.quantity = quantity;
+    }
+
+    public Double getPrice() {
+        return price;
+    }
+
+    public void setPrice(Double price) {
+        this.price = price;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) {
+            return true;
+        }
+        if (o == null || getClass() != o.getClass()) {
+            return false;
+        }
+
+        BookDTO bookDTO = (BookDTO) o;
+        if (bookDTO.getId() == null || getId() == null) {
+            return false;
+        }
+        return Objects.equals(getId(), bookDTO.getId());
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hashCode(getId());
+    }
+
+    @Override
+    public String toString() {
+        return "BookDTO{" +
+            "id=" + getId() +
+            ", title='" + getTitle() + "'" +
+            ", author='" + getAuthor() + "'" +
+            ", published='" + getPublished() + "'" +
+            ", quantity=" + getQuantity() +
+            ", price=" + getPrice() +
+            "}";
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/service/dto/PasswordChangeDTO.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/service/dto/PasswordChangeDTO.java
@ -0,0 +1,35 @@
+package com.baeldung.jhipster6.service.dto;
+
+/**
+ * A DTO representing a password change required data - current and new password.
+ */
+public class PasswordChangeDTO {
+    private String currentPassword;
+    private String newPassword;
+
+    public PasswordChangeDTO() {
+        // Empty constructor needed for Jackson.
+    }
+
+    public PasswordChangeDTO(String currentPassword, String newPassword) {
+        this.currentPassword = currentPassword;
+        this.newPassword = newPassword;
+    }
+
+    public String getCurrentPassword() {
+
+        return currentPassword;
+    }
+
+    public void setCurrentPassword(String currentPassword) {
+        this.currentPassword = currentPassword;
+    }
+
+    public String getNewPassword() {
+        return newPassword;
+    }
+
+    public void setNewPassword(String newPassword) {
+        this.newPassword = newPassword;
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/service/dto/UserDTO.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/service/dto/UserDTO.java
@ -0,0 +1,199 @@
+package com.baeldung.jhipster6.service.dto;
+
+import com.baeldung.jhipster6.config.Constants;
+
+import com.baeldung.jhipster6.domain.Authority;
+import com.baeldung.jhipster6.domain.User;
+
+import javax.validation.constraints.Email;
+import javax.validation.constraints.NotBlank;
+
+import javax.validation.constraints.*;
+import java.time.Instant;
+import java.util.Set;
+import java.util.stream.Collectors;
+
+/**
+ * A DTO representing a user, with his authorities.
+ */
+public class UserDTO {
+
+    private Long id;
+
+    @NotBlank
+    @Pattern(regexp = Constants.LOGIN_REGEX)
+    @Size(min = 1, max = 50)
+    private String login;
+
+    @Size(max = 50)
+    private String firstName;
+
+    @Size(max = 50)
+    private String lastName;
+
+    @Email
+    @Size(min = 5, max = 254)
+    private String email;
+
+    @Size(max = 256)
+    private String imageUrl;
+
+    private boolean activated = false;
+
+    @Size(min = 2, max = 6)
+    private String langKey;
+
+    private String createdBy;
+
+    private Instant createdDate;
+
+    private String lastModifiedBy;
+
+    private Instant lastModifiedDate;
+
+    private Set<String> authorities;
+
+    public UserDTO() {
+        // Empty constructor needed for Jackson.
+    }
+
+    public UserDTO(User user) {
+        this.id = user.getId();
+        this.login = user.getLogin();
+        this.firstName = user.getFirstName();
+        this.lastName = user.getLastName();
+        this.email = user.getEmail();
+        this.activated = user.getActivated();
+        this.imageUrl = user.getImageUrl();
+        this.langKey = user.getLangKey();
+        this.createdBy = user.getCreatedBy();
+        this.createdDate = user.getCreatedDate();
+        this.lastModifiedBy = user.getLastModifiedBy();
+        this.lastModifiedDate = user.getLastModifiedDate();
+        this.authorities = user.getAuthorities().stream()
+            .map(Authority::getName)
+            .collect(Collectors.toSet());
+    }
+
+    public Long getId() {
+        return id;
+    }
+
+    public void setId(Long id) {
+        this.id = id;
+    }
+
+    public String getLogin() {
+        return login;
+    }
+
+    public void setLogin(String login) {
+        this.login = login;
+    }
+
+    public String getFirstName() {
+        return firstName;
+    }
+
+    public void setFirstName(String firstName) {
+        this.firstName = firstName;
+    }
+
+    public String getLastName() {
+        return lastName;
+    }
+
+    public void setLastName(String lastName) {
+        this.lastName = lastName;
+    }
+
+    public String getEmail() {
+        return email;
+    }
+
+    public void setEmail(String email) {
+        this.email = email;
+    }
+
+    public String getImageUrl() {
+        return imageUrl;
+    }
+
+    public void setImageUrl(String imageUrl) {
+        this.imageUrl = imageUrl;
+    }
+
+    public boolean isActivated() {
+        return activated;
+    }
+
+    public void setActivated(boolean activated) {
+        this.activated = activated;
+    }
+
+    public String getLangKey() {
+        return langKey;
+    }
+
+    public void setLangKey(String langKey) {
+        this.langKey = langKey;
+    }
+
+    public String getCreatedBy() {
+        return createdBy;
+    }
+
+    public void setCreatedBy(String createdBy) {
+        this.createdBy = createdBy;
+    }
+
+    public Instant getCreatedDate() {
+        return createdDate;
+    }
+
+    public void setCreatedDate(Instant createdDate) {
+        this.createdDate = createdDate;
+    }
+
+    public String getLastModifiedBy() {
+        return lastModifiedBy;
+    }
+
+    public void setLastModifiedBy(String lastModifiedBy) {
+        this.lastModifiedBy = lastModifiedBy;
+    }
+
+    public Instant getLastModifiedDate() {
+        return lastModifiedDate;
+    }
+
+    public void setLastModifiedDate(Instant lastModifiedDate) {
+        this.lastModifiedDate = lastModifiedDate;
+    }
+
+    public Set<String> getAuthorities() {
+        return authorities;
+    }
+
+    public void setAuthorities(Set<String> authorities) {
+        this.authorities = authorities;
+    }
+
+    @Override
+    public String toString() {
+        return "UserDTO{" +
+            "login='" + login + '\'' +
+            ", firstName='" + firstName + '\'' +
+            ", lastName='" + lastName + '\'' +
+            ", email='" + email + '\'' +
+            ", imageUrl='" + imageUrl + '\'' +
+            ", activated=" + activated +
+            ", langKey='" + langKey + '\'' +
+            ", createdBy=" + createdBy +
+            ", createdDate=" + createdDate +
+            ", lastModifiedBy='" + lastModifiedBy + '\'' +
+            ", lastModifiedDate=" + lastModifiedDate +
+            ", authorities=" + authorities +
+            "}";
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/service/dto/package-info.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/service/dto/package-info.java
@ -0,0 +1,4 @@
+/**
+ * Data Transfer Objects.
+ */
+package com.baeldung.jhipster6.service.dto;
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/service/impl/BookServiceImpl.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/service/impl/BookServiceImpl.java
@ -0,0 +1,110 @@
+package com.baeldung.jhipster6.service.impl;
+
+import com.baeldung.jhipster6.service.BookService;
+import com.baeldung.jhipster6.domain.Book;
+import com.baeldung.jhipster6.repository.BookRepository;
+import com.baeldung.jhipster6.service.dto.BookDTO;
+import com.baeldung.jhipster6.service.mapper.BookMapper;
+import com.baeldung.jhipster6.web.rest.errors.BadRequestAlertException;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+
+import java.util.LinkedList;
+import java.util.List;
+import java.util.Optional;
+import java.util.stream.Collectors;
+
+/**
+ * Service Implementation for managing Book.
+ */
+@Service
+@Transactional
+public class BookServiceImpl implements BookService {
+
+    private final Logger log = LoggerFactory.getLogger(BookServiceImpl.class);
+
+    private final BookRepository bookRepository;
+
+    private final BookMapper bookMapper;
+
+    public BookServiceImpl(BookRepository bookRepository, BookMapper bookMapper) {
+        this.bookRepository = bookRepository;
+        this.bookMapper = bookMapper;
+    }
+
+    /**
+     * Save a book.
+     *
+     * @param bookDTO the entity to save
+     * @return the persisted entity
+     */
+    @Override
+    public BookDTO save(BookDTO bookDTO) {
+        log.debug("Request to save Book : {}", bookDTO);
+        Book book = bookMapper.toEntity(bookDTO);
+        book = bookRepository.save(book);
+        return bookMapper.toDto(book);
+    }
+
+    /**
+     * Get all the books.
+     *
+     * @return the list of entities
+     */
+    @Override
+    @Transactional(readOnly = true)
+    public List<BookDTO> findAll() {
+        log.debug("Request to get all Books");
+        return bookRepository.findAll().stream()
+            .map(bookMapper::toDto)
+            .collect(Collectors.toCollection(LinkedList::new));
+    }
+
+
+    /**
+     * Get one book by id.
+     *
+     * @param id the id of the entity
+     * @return the entity
+     */
+    @Override
+    @Transactional(readOnly = true)
+    public Optional<BookDTO> findOne(Long id) {
+        log.debug("Request to get Book : {}", id);
+        return bookRepository.findById(id)
+            .map(bookMapper::toDto);
+    }
+
+    /**
+     * Delete the book by id.
+     *
+     * @param id the id of the entity
+     */
+    @Override
+    public void delete(Long id) {
+        log.debug("Request to delete Book : {}", id);
+        bookRepository.deleteById(id);
+    }
+
+    @Override
+    public Optional<BookDTO> purchase(Long id) {
+        Optional<BookDTO> bookDTO = findOne(id);
+        if(bookDTO.isPresent()) {
+            int quantity = bookDTO.get().getQuantity();
+            if(quantity > 0) {
+                bookDTO.get().setQuantity(quantity - 1);
+                Book book = bookMapper.toEntity(bookDTO.get());
+                book = bookRepository.save(book);
+                return bookDTO;
+            }
+            else {
+                throw new BadRequestAlertException("Book is not in stock", "book", "notinstock");
+            }
+        }
+        return Optional.empty();
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/service/mapper/BookMapper.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/service/mapper/BookMapper.java
@ -0,0 +1,25 @@
+package com.baeldung.jhipster6.service.mapper;
+
+import com.baeldung.jhipster6.domain.*;
+import com.baeldung.jhipster6.service.dto.BookDTO;
+import com.baeldung.jhipster6.domain.Book;
+
+import org.mapstruct.*;
+
+/**
+ * Mapper for the entity Book and its DTO BookDTO.
+ */
+@Mapper(componentModel = "spring", uses = {})
+public interface BookMapper extends EntityMapper<BookDTO, Book> {
+
+
+
+    default Book fromId(Long id) {
+        if (id == null) {
+            return null;
+        }
+        Book book = new Book();
+        book.setId(id);
+        return book;
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/service/mapper/EntityMapper.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/service/mapper/EntityMapper.java
@ -0,0 +1,21 @@
+package com.baeldung.jhipster6.service.mapper;
+
+import java.util.List;
+
+/**
+ * Contract for a generic dto to entity mapper.
+ *
+ * @param <D> - DTO type parameter.
+ * @param <E> - Entity type parameter.
+ */
+
+public interface EntityMapper <D, E> {
+
+    E toEntity(D dto);
+
+    D toDto(E entity);
+
+    List <E> toEntity(List<D> dtoList);
+
+    List <D> toDto(List<E> entityList);
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/service/mapper/UserMapper.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/service/mapper/UserMapper.java
@ -0,0 +1,81 @@
+package com.baeldung.jhipster6.service.mapper;
+
+import com.baeldung.jhipster6.domain.Authority;
+import com.baeldung.jhipster6.domain.User;
+import com.baeldung.jhipster6.service.dto.UserDTO;
+
+import org.springframework.stereotype.Service;
+
+import java.util.*;
+import java.util.stream.Collectors;
+
+/**
+ * Mapper for the entity User and its DTO called UserDTO.
+ *
+ * Normal mappers are generated using MapStruct, this one is hand-coded as MapStruct
+ * support is still in beta, and requires a manual step with an IDE.
+ */
+@Service
+public class UserMapper {
+
+    public List<UserDTO> usersToUserDTOs(List<User> users) {
+        return users.stream()
+            .filter(Objects::nonNull)
+            .map(this::userToUserDTO)
+            .collect(Collectors.toList());
+    }
+
+    public UserDTO userToUserDTO(User user) {
+        return new UserDTO(user);
+    }
+
+    public List<User> userDTOsToUsers(List<UserDTO> userDTOs) {
+        return userDTOs.stream()
+            .filter(Objects::nonNull)
+            .map(this::userDTOToUser)
+            .collect(Collectors.toList());
+    }
+
+    public User userDTOToUser(UserDTO userDTO) {
+        if (userDTO == null) {
+            return null;
+        } else {
+            User user = new User();
+            user.setId(userDTO.getId());
+            user.setLogin(userDTO.getLogin());
+            user.setFirstName(userDTO.getFirstName());
+            user.setLastName(userDTO.getLastName());
+            user.setEmail(userDTO.getEmail());
+            user.setImageUrl(userDTO.getImageUrl());
+            user.setActivated(userDTO.isActivated());
+            user.setLangKey(userDTO.getLangKey());
+            Set<Authority> authorities = this.authoritiesFromStrings(userDTO.getAuthorities());
+            user.setAuthorities(authorities);
+            return user;
+        }
+    }
+
+
+    private Set<Authority> authoritiesFromStrings(Set<String> authoritiesAsString) {
+        Set<Authority> authorities = new HashSet<>();
+
+        if(authoritiesAsString != null){
+            authorities = authoritiesAsString.stream().map(string -> {
+                Authority auth = new Authority();
+                auth.setName(string);
+                return auth;
+            }).collect(Collectors.toSet());
+        }
+
+        return authorities;
+    }
+
+    public User userFromId(Long id) {
+        if (id == null) {
+            return null;
+        }
+        User user = new User();
+        user.setId(id);
+        return user;
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/service/mapper/package-info.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/service/mapper/package-info.java
@ -0,0 +1,4 @@
+/**
+ * MapStruct mappers for mapping domain objects and Data Transfer Objects.
+ */
+package com.baeldung.jhipster6.service.mapper;
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/service/package-info.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/service/package-info.java
@ -0,0 +1,4 @@
+/**
+ * Service layer beans.
+ */
+package com.baeldung.jhipster6.service;
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/service/util/RandomUtil.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/service/util/RandomUtil.java
@ -0,0 +1,41 @@
+package com.baeldung.jhipster6.service.util;
+
+import org.apache.commons.lang3.RandomStringUtils;
+
+/**
+ * Utility class for generating random Strings.
+ */
+public final class RandomUtil {
+
+    private static final int DEF_COUNT = 20;
+
+    private RandomUtil() {
+    }
+
+    /**
+     * Generate a password.
+     *
+     * @return the generated password
+     */
+    public static String generatePassword() {
+        return RandomStringUtils.randomAlphanumeric(DEF_COUNT);
+    }
+
+    /**
+     * Generate an activation key.
+     *
+     * @return the generated activation key
+     */
+    public static String generateActivationKey() {
+        return RandomStringUtils.randomNumeric(DEF_COUNT);
+    }
+
+    /**
+     * Generate a reset key.
+     *
+     * @return the generated reset key
+     */
+    public static String generateResetKey() {
+        return RandomStringUtils.randomNumeric(DEF_COUNT);
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/web/rest/AccountResource.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/web/rest/AccountResource.java
@ -0,0 +1,184 @@
+package com.baeldung.jhipster6.web.rest;
+
+
+import com.baeldung.jhipster6.domain.User;
+import com.baeldung.jhipster6.repository.UserRepository;
+import com.baeldung.jhipster6.security.SecurityUtils;
+import com.baeldung.jhipster6.service.MailService;
+import com.baeldung.jhipster6.service.UserService;
+import com.baeldung.jhipster6.service.dto.PasswordChangeDTO;
+import com.baeldung.jhipster6.service.dto.UserDTO;
+import com.baeldung.jhipster6.web.rest.errors.*;
+import com.baeldung.jhipster6.web.rest.errors.EmailAlreadyUsedException;
+import com.baeldung.jhipster6.web.rest.errors.EmailNotFoundException;
+import com.baeldung.jhipster6.web.rest.errors.InternalServerErrorException;
+import com.baeldung.jhipster6.web.rest.errors.InvalidPasswordException;
+import com.baeldung.jhipster6.web.rest.errors.LoginAlreadyUsedException;
+import com.baeldung.jhipster6.web.rest.vm.KeyAndPasswordVM;
+import com.baeldung.jhipster6.web.rest.vm.ManagedUserVM;
+
+import org.apache.commons.lang3.StringUtils;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.http.HttpStatus;
+import org.springframework.web.bind.annotation.*;
+
+import javax.servlet.http.HttpServletRequest;
+import javax.validation.Valid;
+import java.util.*;
+
+/**
+ * REST controller for managing the current user's account.
+ */
+@RestController
+@RequestMapping("/api")
+public class AccountResource {
+
+    private final Logger log = LoggerFactory.getLogger(AccountResource.class);
+
+    private final UserRepository userRepository;
+
+    private final UserService userService;
+
+    private final MailService mailService;
+
+    public AccountResource(UserRepository userRepository, UserService userService, MailService mailService) {
+
+        this.userRepository = userRepository;
+        this.userService = userService;
+        this.mailService = mailService;
+    }
+
+    /**
+     * POST  /register : register the user.
+     *
+     * @param managedUserVM the managed user View Model
+     * @throws InvalidPasswordException 400 (Bad Request) if the password is incorrect
+     * @throws EmailAlreadyUsedException 400 (Bad Request) if the email is already used
+     * @throws LoginAlreadyUsedException 400 (Bad Request) if the login is already used
+     */
+    @PostMapping("/register")
+    @ResponseStatus(HttpStatus.CREATED)
+    public void registerAccount(@Valid @RequestBody ManagedUserVM managedUserVM) {
+        if (!checkPasswordLength(managedUserVM.getPassword())) {
+            throw new InvalidPasswordException();
+        }
+        User user = userService.registerUser(managedUserVM, managedUserVM.getPassword());
+        mailService.sendActivationEmail(user);
+    }
+
+    /**
+     * GET  /activate : activate the registered user.
+     *
+     * @param key the activation key
+     * @throws RuntimeException 500 (Internal Server Error) if the user couldn't be activated
+     */
+    @GetMapping("/activate")
+    public void activateAccount(@RequestParam(value = "key") String key) {
+        Optional<User> user = userService.activateRegistration(key);
+        if (!user.isPresent()) {
+            throw new InternalServerErrorException("No user was found for this activation key");
+        }
+    }
+
+    /**
+     * GET  /authenticate : check if the user is authenticated, and return its login.
+     *
+     * @param request the HTTP request
+     * @return the login if the user is authenticated
+     */
+    @GetMapping("/authenticate")
+    public String isAuthenticated(HttpServletRequest request) {
+        log.debug("REST request to check if the current user is authenticated");
+        return request.getRemoteUser();
+    }
+
+    /**
+     * GET  /account : get the current user.
+     *
+     * @return the current user
+     * @throws RuntimeException 500 (Internal Server Error) if the user couldn't be returned
+     */
+    @GetMapping("/account")
+    public UserDTO getAccount() {
+        return userService.getUserWithAuthorities()
+            .map(UserDTO::new)
+            .orElseThrow(() -> new InternalServerErrorException("User could not be found"));
+    }
+
+    /**
+     * POST  /account : update the current user information.
+     *
+     * @param userDTO the current user information
+     * @throws EmailAlreadyUsedException 400 (Bad Request) if the email is already used
+     * @throws RuntimeException 500 (Internal Server Error) if the user login wasn't found
+     */
+    @PostMapping("/account")
+    public void saveAccount(@Valid @RequestBody UserDTO userDTO) {
+        String userLogin = SecurityUtils.getCurrentUserLogin().orElseThrow(() -> new InternalServerErrorException("Current user login not found"));
+        Optional<User> existingUser = userRepository.findOneByEmailIgnoreCase(userDTO.getEmail());
+        if (existingUser.isPresent() && (!existingUser.get().getLogin().equalsIgnoreCase(userLogin))) {
+            throw new EmailAlreadyUsedException();
+        }
+        Optional<User> user = userRepository.findOneByLogin(userLogin);
+        if (!user.isPresent()) {
+            throw new InternalServerErrorException("User could not be found");
+        }
+        userService.updateUser(userDTO.getFirstName(), userDTO.getLastName(), userDTO.getEmail(),
+            userDTO.getLangKey(), userDTO.getImageUrl());
+    }
+
+    /**
+     * POST  /account/change-password : changes the current user's password
+     *
+     * @param passwordChangeDto current and new password
+     * @throws InvalidPasswordException 400 (Bad Request) if the new password is incorrect
+     */
+    @PostMapping(path = "/account/change-password")
+    public void changePassword(@RequestBody PasswordChangeDTO passwordChangeDto) {
+        if (!checkPasswordLength(passwordChangeDto.getNewPassword())) {
+            throw new InvalidPasswordException();
+        }
+        userService.changePassword(passwordChangeDto.getCurrentPassword(), passwordChangeDto.getNewPassword());
+    }
+
+    /**
+     * POST   /account/reset-password/init : Send an email to reset the password of the user
+     *
+     * @param mail the mail of the user
+     * @throws EmailNotFoundException 400 (Bad Request) if the email address is not registered
+     */
+    @PostMapping(path = "/account/reset-password/init")
+    public void requestPasswordReset(@RequestBody String mail) {
+       mailService.sendPasswordResetMail(
+           userService.requestPasswordReset(mail)
+               .orElseThrow(EmailNotFoundException::new)
+       );
+    }
+
+    /**
+     * POST   /account/reset-password/finish : Finish to reset the password of the user
+     *
+     * @param keyAndPassword the generated key and the new password
+     * @throws InvalidPasswordException 400 (Bad Request) if the password is incorrect
+     * @throws RuntimeException 500 (Internal Server Error) if the password could not be reset
+     */
+    @PostMapping(path = "/account/reset-password/finish")
+    public void finishPasswordReset(@RequestBody KeyAndPasswordVM keyAndPassword) {
+        if (!checkPasswordLength(keyAndPassword.getNewPassword())) {
+            throw new InvalidPasswordException();
+        }
+        Optional<User> user =
+            userService.completePasswordReset(keyAndPassword.getNewPassword(), keyAndPassword.getKey());
+
+        if (!user.isPresent()) {
+            throw new InternalServerErrorException("No user was found for this reset key");
+        }
+    }
+
+    private static boolean checkPasswordLength(String password) {
+        return !StringUtils.isEmpty(password) &&
+            password.length() >= ManagedUserVM.PASSWORD_MIN_LENGTH &&
+            password.length() <= ManagedUserVM.PASSWORD_MAX_LENGTH;
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/web/rest/AuditResource.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/web/rest/AuditResource.java
@ -0,0 +1,77 @@
+package com.baeldung.jhipster6.web.rest;
+
+import com.baeldung.jhipster6.service.AuditEventService;
+import com.baeldung.jhipster6.web.rest.util.PaginationUtil;
+
+import io.github.jhipster.web.util.ResponseUtil;
+import org.springframework.boot.actuate.audit.AuditEvent;
+import org.springframework.data.domain.Page;
+import org.springframework.data.domain.Pageable;
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.*;
+
+import java.time.LocalDate;
+import java.time.ZoneId;
+import java.util.List;
+
+/**
+ * REST controller for getting the audit events.
+ */
+@RestController
+@RequestMapping("/management/audits")
+public class AuditResource {
+
+    private final AuditEventService auditEventService;
+
+    public AuditResource(AuditEventService auditEventService) {
+        this.auditEventService = auditEventService;
+    }
+
+    /**
+     * GET /audits : get a page of AuditEvents.
+     *
+     * @param pageable the pagination information
+     * @return the ResponseEntity with status 200 (OK) and the list of AuditEvents in body
+     */
+    @GetMapping
+    public ResponseEntity<List<AuditEvent>> getAll(Pageable pageable) {
+        Page<AuditEvent> page = auditEventService.findAll(pageable);
+        HttpHeaders headers = PaginationUtil.generatePaginationHttpHeaders(page, "/management/audits");
+        return new ResponseEntity<>(page.getContent(), headers, HttpStatus.OK);
+    }
+
+    /**
+     * GET  /audits : get a page of AuditEvents between the fromDate and toDate.
+     *
+     * @param fromDate the start of the time period of AuditEvents to get
+     * @param toDate the end of the time period of AuditEvents to get
+     * @param pageable the pagination information
+     * @return the ResponseEntity with status 200 (OK) and the list of AuditEvents in body
+     */
+    @GetMapping(params = {"fromDate", "toDate"})
+    public ResponseEntity<List<AuditEvent>> getByDates(
+        @RequestParam(value = "fromDate") LocalDate fromDate,
+        @RequestParam(value = "toDate") LocalDate toDate,
+        Pageable pageable) {
+
+        Page<AuditEvent> page = auditEventService.findByDates(
+            fromDate.atStartOfDay(ZoneId.systemDefault()).toInstant(),
+            toDate.atStartOfDay(ZoneId.systemDefault()).plusDays(1).toInstant(),
+            pageable);
+        HttpHeaders headers = PaginationUtil.generatePaginationHttpHeaders(page, "/management/audits");
+        return new ResponseEntity<>(page.getContent(), headers, HttpStatus.OK);
+    }
+
+    /**
+     * GET  /audits/:id : get an AuditEvent by id.
+     *
+     * @param id the id of the entity to get
+     * @return the ResponseEntity with status 200 (OK) and the AuditEvent in body, or status 404 (Not Found)
+     */
+    @GetMapping("/{id:.+}")
+    public ResponseEntity<AuditEvent> get(@PathVariable Long id) {
+        return ResponseUtil.wrapOrNotFound(auditEventService.find(id));
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/web/rest/BookResource.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/web/rest/BookResource.java
@ -0,0 +1,118 @@
+package com.baeldung.jhipster6.web.rest;
+import com.baeldung.jhipster6.service.BookService;
+import com.baeldung.jhipster6.web.rest.errors.BadRequestAlertException;
+import com.baeldung.jhipster6.web.rest.util.HeaderUtil;
+import com.baeldung.jhipster6.service.dto.BookDTO;
+import io.github.jhipster.web.util.ResponseUtil;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.*;
+
+import javax.validation.Valid;
+import java.net.URI;
+import java.net.URISyntaxException;
+
+import java.util.List;
+import java.util.Optional;
+
+/**
+ * REST controller for managing Book.
+ */
+@RestController
+@RequestMapping("/api")
+public class BookResource {
+
+    private final Logger log = LoggerFactory.getLogger(BookResource.class);
+
+    private static final String ENTITY_NAME = "book";
+
+    private final BookService bookService;
+
+    public BookResource(BookService bookService) {
+        this.bookService = bookService;
+    }
+
+    /**
+     * POST  /books : Create a new book.
+     *
+     * @param bookDTO the bookDTO to create
+     * @return the ResponseEntity with status 201 (Created) and with body the new bookDTO, or with status 400 (Bad Request) if the book has already an ID
+     * @throws URISyntaxException if the Location URI syntax is incorrect
+     */
+    @PostMapping("/books")
+    public ResponseEntity<BookDTO> createBook(@Valid @RequestBody BookDTO bookDTO) throws URISyntaxException {
+        log.debug("REST request to save Book : {}", bookDTO);
+        if (bookDTO.getId() != null) {
+            throw new BadRequestAlertException("A new book cannot already have an ID", ENTITY_NAME, "idexists");
+        }
+        BookDTO result = bookService.save(bookDTO);
+        return ResponseEntity.created(new URI("/api/books/" + result.getId()))
+            .headers(HeaderUtil.createEntityCreationAlert(ENTITY_NAME, result.getId().toString()))
+            .body(result);
+    }
+
+    /**
+     * PUT  /books : Updates an existing book.
+     *
+     * @param bookDTO the bookDTO to update
+     * @return the ResponseEntity with status 200 (OK) and with body the updated bookDTO,
+     * or with status 400 (Bad Request) if the bookDTO is not valid,
+     * or with status 500 (Internal Server Error) if the bookDTO couldn't be updated
+     * @throws URISyntaxException if the Location URI syntax is incorrect
+     */
+    @PutMapping("/books")
+    public ResponseEntity<BookDTO> updateBook(@Valid @RequestBody BookDTO bookDTO) throws URISyntaxException {
+        log.debug("REST request to update Book : {}", bookDTO);
+        if (bookDTO.getId() == null) {
+            throw new BadRequestAlertException("Invalid id", ENTITY_NAME, "idnull");
+        }
+        BookDTO result = bookService.save(bookDTO);
+        return ResponseEntity.ok()
+            .headers(HeaderUtil.createEntityUpdateAlert(ENTITY_NAME, bookDTO.getId().toString()))
+            .body(result);
+    }
+
+    /**
+     * GET  /books : get all the books.
+     *
+     * @return the ResponseEntity with status 200 (OK) and the list of books in body
+     */
+    @GetMapping("/books")
+    public List<BookDTO> getAllBooks() {
+        log.debug("REST request to get all Books");
+        return bookService.findAll();
+    }
+
+    /**
+     * GET  /books/:id : get the "id" book.
+     *
+     * @param id the id of the bookDTO to retrieve
+     * @return the ResponseEntity with status 200 (OK) and with body the bookDTO, or with status 404 (Not Found)
+     */
+    @GetMapping("/books/{id}")
+    public ResponseEntity<BookDTO> getBook(@PathVariable Long id) {
+        log.debug("REST request to get Book : {}", id);
+        Optional<BookDTO> bookDTO = bookService.findOne(id);
+        return ResponseUtil.wrapOrNotFound(bookDTO);
+    }
+
+    /**
+     * DELETE  /books/:id : delete the "id" book.
+     *
+     * @param id the id of the bookDTO to delete
+     * @return the ResponseEntity with status 200 (OK)
+     */
+    @DeleteMapping("/books/{id}")
+    public ResponseEntity<Void> deleteBook(@PathVariable Long id) {
+        log.debug("REST request to delete Book : {}", id);
+        bookService.delete(id);
+        return ResponseEntity.ok().headers(HeaderUtil.createEntityDeletionAlert(ENTITY_NAME, id.toString())).build();
+    }
+
+    @GetMapping("/books/purchase/{id}")
+    public ResponseEntity<BookDTO> purchase(@PathVariable Long id) {
+        Optional<BookDTO> bookDTO = bookService.purchase(id);
+        return ResponseUtil.wrapOrNotFound(bookDTO);
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/web/rest/ClientForwardController.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/web/rest/ClientForwardController.java
@ -0,0 +1,17 @@
+package com.baeldung.jhipster6.web.rest;
+
+import org.springframework.stereotype.Controller;
+import org.springframework.web.bind.annotation.GetMapping;
+
+@Controller
+public class ClientForwardController {
+
+    /**
+     * Forwards any unmapped paths (except those containing a period) to the client {@code index.html}.
+     * @return forward to client {@code index.html}.
+     */
+    @GetMapping(value = "/**/{path:[^\\.]*}")
+    public String forward() {
+        return "forward:/";
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/web/rest/LogsResource.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/web/rest/LogsResource.java
@ -0,0 +1,36 @@
+package com.baeldung.jhipster6.web.rest;
+
+import com.baeldung.jhipster6.web.rest.vm.LoggerVM;
+
+import ch.qos.logback.classic.Level;
+import ch.qos.logback.classic.LoggerContext;
+import org.slf4j.LoggerFactory;
+import org.springframework.http.HttpStatus;
+import org.springframework.web.bind.annotation.*;
+
+import java.util.List;
+import java.util.stream.Collectors;
+
+/**
+ * Controller for view and managing Log Level at runtime.
+ */
+@RestController
+@RequestMapping("/management")
+public class LogsResource {
+
+    @GetMapping("/logs")
+    public List<LoggerVM> getList() {
+        LoggerContext context = (LoggerContext) LoggerFactory.getILoggerFactory();
+        return context.getLoggerList()
+            .stream()
+            .map(LoggerVM::new)
+            .collect(Collectors.toList());
+    }
+
+    @PutMapping("/logs")
+    @ResponseStatus(HttpStatus.NO_CONTENT)
+    public void changeLevel(@RequestBody LoggerVM jsonLogger) {
+        LoggerContext context = (LoggerContext) LoggerFactory.getILoggerFactory();
+        context.getLogger(jsonLogger.getName()).setLevel(Level.valueOf(jsonLogger.getLevel()));
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/web/rest/UserJWTController.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/web/rest/UserJWTController.java
@ -0,0 +1,71 @@
+package com.baeldung.jhipster6.web.rest;
+
+import com.baeldung.jhipster6.security.jwt.JWTFilter;
+import com.baeldung.jhipster6.security.jwt.TokenProvider;
+import com.baeldung.jhipster6.web.rest.vm.LoginVM;
+
+import com.fasterxml.jackson.annotation.JsonProperty;
+
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseEntity;
+import org.springframework.security.authentication.AuthenticationManager;
+import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
+import org.springframework.security.core.Authentication;
+import org.springframework.security.core.context.SecurityContextHolder;
+import org.springframework.web.bind.annotation.*;
+
+import javax.validation.Valid;
+
+/**
+ * Controller to authenticate users.
+ */
+@RestController
+@RequestMapping("/api")
+public class UserJWTController {
+
+    private final TokenProvider tokenProvider;
+
+    private final AuthenticationManager authenticationManager;
+
+    public UserJWTController(TokenProvider tokenProvider, AuthenticationManager authenticationManager) {
+        this.tokenProvider = tokenProvider;
+        this.authenticationManager = authenticationManager;
+    }
+
+    @PostMapping("/authenticate")
+    public ResponseEntity<JWTToken> authorize(@Valid @RequestBody LoginVM loginVM) {
+
+        UsernamePasswordAuthenticationToken authenticationToken =
+            new UsernamePasswordAuthenticationToken(loginVM.getUsername(), loginVM.getPassword());
+
+        Authentication authentication = this.authenticationManager.authenticate(authenticationToken);
+        SecurityContextHolder.getContext().setAuthentication(authentication);
+        boolean rememberMe = (loginVM.isRememberMe() == null) ? false : loginVM.isRememberMe();
+        String jwt = tokenProvider.createToken(authentication, rememberMe);
+        HttpHeaders httpHeaders = new HttpHeaders();
+        httpHeaders.add(JWTFilter.AUTHORIZATION_HEADER, "Bearer " + jwt);
+        return new ResponseEntity<>(new JWTToken(jwt), httpHeaders, HttpStatus.OK);
+    }
+
+    /**
+     * Object to return as body in JWT Authentication.
+     */
+    static class JWTToken {
+
+        private String idToken;
+
+        JWTToken(String idToken) {
+            this.idToken = idToken;
+        }
+
+        @JsonProperty("id_token")
+        String getIdToken() {
+            return idToken;
+        }
+
+        void setIdToken(String idToken) {
+            this.idToken = idToken;
+        }
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/web/rest/UserResource.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/web/rest/UserResource.java
@ -0,0 +1,183 @@
+package com.baeldung.jhipster6.web.rest;
+
+import com.baeldung.jhipster6.config.Constants;
+import com.baeldung.jhipster6.domain.User;
+import com.baeldung.jhipster6.repository.UserRepository;
+import com.baeldung.jhipster6.security.AuthoritiesConstants;
+import com.baeldung.jhipster6.service.MailService;
+import com.baeldung.jhipster6.service.UserService;
+import com.baeldung.jhipster6.service.dto.UserDTO;
+import com.baeldung.jhipster6.web.rest.errors.BadRequestAlertException;
+import com.baeldung.jhipster6.web.rest.errors.EmailAlreadyUsedException;
+import com.baeldung.jhipster6.web.rest.errors.LoginAlreadyUsedException;
+import com.baeldung.jhipster6.web.rest.util.HeaderUtil;
+import com.baeldung.jhipster6.web.rest.util.PaginationUtil;
+import io.github.jhipster.web.util.ResponseUtil;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.data.domain.Page;
+import org.springframework.data.domain.Pageable;
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseEntity;
+import org.springframework.security.access.prepost.PreAuthorize;
+import org.springframework.web.bind.annotation.*;
+
+import javax.validation.Valid;
+import java.net.URI;
+import java.net.URISyntaxException;
+import java.util.*;
+
+/**
+ * REST controller for managing users.
+ * <p>
+ * This class accesses the User entity, and needs to fetch its collection of authorities.
+ * <p>
+ * For a normal use-case, it would be better to have an eager relationship between User and Authority,
+ * and send everything to the client side: there would be no View Model and DTO, a lot less code, and an outer-join
+ * which would be good for performance.
+ * <p>
+ * We use a View Model and a DTO for 3 reasons:
+ * <ul>
+ * <li>We want to keep a lazy association between the user and the authorities, because people will
+ * quite often do relationships with the user, and we don't want them to get the authorities all
+ * the time for nothing (for performance reasons). This is the #1 goal: we should not impact our users'
+ * application because of this use-case.</li>
+ * <li> Not having an outer join causes n+1 requests to the database. This is not a real issue as
+ * we have by default a second-level cache. This means on the first HTTP call we do the n+1 requests,
+ * but then all authorities come from the cache, so in fact it's much better than doing an outer join
+ * (which will get lots of data from the database, for each HTTP call).</li>
+ * <li> As this manages users, for security reasons, we'd rather have a DTO layer.</li>
+ * </ul>
+ * <p>
+ * Another option would be to have a specific JPA entity graph to handle this case.
+ */
+@RestController
+@RequestMapping("/api")
+public class UserResource {
+
+    private final Logger log = LoggerFactory.getLogger(UserResource.class);
+
+    private final UserService userService;
+
+    private final UserRepository userRepository;
+
+    private final MailService mailService;
+
+    public UserResource(UserService userService, UserRepository userRepository, MailService mailService) {
+
+        this.userService = userService;
+        this.userRepository = userRepository;
+        this.mailService = mailService;
+    }
+
+    /**
+     * POST  /users  : Creates a new user.
+     * <p>
+     * Creates a new user if the login and email are not already used, and sends an
+     * mail with an activation link.
+     * The user needs to be activated on creation.
+     *
+     * @param userDTO the user to create
+     * @return the ResponseEntity with status 201 (Created) and with body the new user, or with status 400 (Bad Request) if the login or email is already in use
+     * @throws URISyntaxException if the Location URI syntax is incorrect
+     * @throws BadRequestAlertException 400 (Bad Request) if the login or email is already in use
+     */
+    @PostMapping("/users")
+    @PreAuthorize("hasRole(\"" + AuthoritiesConstants.ADMIN + "\")")
+    public ResponseEntity<User> createUser(@Valid @RequestBody UserDTO userDTO) throws URISyntaxException {
+        log.debug("REST request to save User : {}", userDTO);
+
+        if (userDTO.getId() != null) {
+            throw new BadRequestAlertException("A new user cannot already have an ID", "userManagement", "idexists");
+            // Lowercase the user login before comparing with database
+        } else if (userRepository.findOneByLogin(userDTO.getLogin().toLowerCase()).isPresent()) {
+            throw new LoginAlreadyUsedException();
+        } else if (userRepository.findOneByEmailIgnoreCase(userDTO.getEmail()).isPresent()) {
+            throw new EmailAlreadyUsedException();
+        } else {
+            User newUser = userService.createUser(userDTO);
+            mailService.sendCreationEmail(newUser);
+            return ResponseEntity.created(new URI("/api/users/" + newUser.getLogin()))
+                .headers(HeaderUtil.createAlert( "A user is created with identifier " + newUser.getLogin(), newUser.getLogin()))
+                .body(newUser);
+        }
+    }
+
+    /**
+     * PUT /users : Updates an existing User.
+     *
+     * @param userDTO the user to update
+     * @return the ResponseEntity with status 200 (OK) and with body the updated user
+     * @throws EmailAlreadyUsedException 400 (Bad Request) if the email is already in use
+     * @throws LoginAlreadyUsedException 400 (Bad Request) if the login is already in use
+     */
+    @PutMapping("/users")
+    @PreAuthorize("hasRole(\"" + AuthoritiesConstants.ADMIN + "\")")
+    public ResponseEntity<UserDTO> updateUser(@Valid @RequestBody UserDTO userDTO) {
+        log.debug("REST request to update User : {}", userDTO);
+        Optional<User> existingUser = userRepository.findOneByEmailIgnoreCase(userDTO.getEmail());
+        if (existingUser.isPresent() && (!existingUser.get().getId().equals(userDTO.getId()))) {
+            throw new EmailAlreadyUsedException();
+        }
+        existingUser = userRepository.findOneByLogin(userDTO.getLogin().toLowerCase());
+        if (existingUser.isPresent() && (!existingUser.get().getId().equals(userDTO.getId()))) {
+            throw new LoginAlreadyUsedException();
+        }
+        Optional<UserDTO> updatedUser = userService.updateUser(userDTO);
+
+        return ResponseUtil.wrapOrNotFound(updatedUser,
+            HeaderUtil.createAlert("A user is updated with identifier " + userDTO.getLogin(), userDTO.getLogin()));
+    }
+
+    /**
+     * GET /users : get all users.
+     *
+     * @param pageable the pagination information
+     * @return the ResponseEntity with status 200 (OK) and with body all users
+     */
+    @GetMapping("/users")
+    public ResponseEntity<List<UserDTO>> getAllUsers(Pageable pageable) {
+        final Page<UserDTO> page = userService.getAllManagedUsers(pageable);
+        HttpHeaders headers = PaginationUtil.generatePaginationHttpHeaders(page, "/api/users");
+        return new ResponseEntity<>(page.getContent(), headers, HttpStatus.OK);
+    }
+
+    /**
+     * @return a string list of the all of the roles
+     */
+    @GetMapping("/users/authorities")
+    @PreAuthorize("hasRole(\"" + AuthoritiesConstants.ADMIN + "\")")
+    public List<String> getAuthorities() {
+        return userService.getAuthorities();
+    }
+
+    /**
+     * GET /users/:login : get the "login" user.
+     *
+     * @param login the login of the user to find
+     * @return the ResponseEntity with status 200 (OK) and with body the "login" user, or with status 404 (Not Found)
+     */
+    @GetMapping("/users/{login:" + Constants.LOGIN_REGEX + "}")
+    public ResponseEntity<UserDTO> getUser(@PathVariable String login) {
+        log.debug("REST request to get User : {}", login);
+        return ResponseUtil.wrapOrNotFound(
+            userService.getUserWithAuthoritiesByLogin(login)
+                .map(UserDTO::new));
+    }
+
+    /**
+     * DELETE /users/:login : delete the "login" User.
+     *
+     * @param login the login of the user to delete
+     * @return the ResponseEntity with status 200 (OK)
+     */
+    @DeleteMapping("/users/{login:" + Constants.LOGIN_REGEX + "}")
+    @PreAuthorize("hasRole(\"" + AuthoritiesConstants.ADMIN + "\")")
+    public ResponseEntity<Void> deleteUser(@PathVariable String login) {
+        log.debug("REST request to delete User: {}", login);
+        userService.deleteUser(login);
+        return ResponseEntity.ok().headers(HeaderUtil.createAlert( "A user is deleted with identifier " + login, login)).build();
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/web/rest/errors/BadRequestAlertException.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/web/rest/errors/BadRequestAlertException.java
@ -0,0 +1,42 @@
+package com.baeldung.jhipster6.web.rest.errors;
+
+import org.zalando.problem.AbstractThrowableProblem;
+import org.zalando.problem.Status;
+
+import java.net.URI;
+import java.util.HashMap;
+import java.util.Map;
+
+public class BadRequestAlertException extends AbstractThrowableProblem {
+
+    private static final long serialVersionUID = 1L;
+
+    private final String entityName;
+
+    private final String errorKey;
+
+    public BadRequestAlertException(String defaultMessage, String entityName, String errorKey) {
+        this(ErrorConstants.DEFAULT_TYPE, defaultMessage, entityName, errorKey);
+    }
+
+    public BadRequestAlertException(URI type, String defaultMessage, String entityName, String errorKey) {
+        super(type, defaultMessage, Status.BAD_REQUEST, null, null, null, getAlertParameters(entityName, errorKey));
+        this.entityName = entityName;
+        this.errorKey = errorKey;
+    }
+
+    public String getEntityName() {
+        return entityName;
+    }
+
+    public String getErrorKey() {
+        return errorKey;
+    }
+
+    private static Map<String, Object> getAlertParameters(String entityName, String errorKey) {
+        Map<String, Object> parameters = new HashMap<>();
+        parameters.put("message", "error." + errorKey);
+        parameters.put("params", entityName);
+        return parameters;
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/web/rest/errors/CustomParameterizedException.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/web/rest/errors/CustomParameterizedException.java
@ -0,0 +1,54 @@
+package com.baeldung.jhipster6.web.rest.errors;
+
+import org.zalando.problem.AbstractThrowableProblem;
+
+import java.util.HashMap;
+import java.util.Map;
+
+import static org.zalando.problem.Status.BAD_REQUEST;
+
+/**
+ * Custom, parameterized exception, which can be translated on the client side.
+ * For example:
+ *
+ * <pre>
+ * throw new CustomParameterizedException(&quot;myCustomError&quot;, &quot;hello&quot;, &quot;world&quot;);
+ * </pre>
+ *
+ * Can be translated with:
+ *
+ * <pre>
+ * "error.myCustomError" :  "The server says {{param0}} to {{param1}}"
+ * </pre>
+ */
+public class CustomParameterizedException extends AbstractThrowableProblem {
+
+    private static final long serialVersionUID = 1L;
+
+    private static final String PARAM = "param";
+
+    public CustomParameterizedException(String message, String... params) {
+        this(message, toParamMap(params));
+    }
+
+    public CustomParameterizedException(String message, Map<String, Object> paramMap) {
+        super(ErrorConstants.PARAMETERIZED_TYPE, "Parameterized Exception", BAD_REQUEST, null, null, null, toProblemParameters(message, paramMap));
+    }
+
+    public static Map<String, Object> toParamMap(String... params) {
+        Map<String, Object> paramMap = new HashMap<>();
+        if (params != null && params.length > 0) {
+            for (int i = 0; i < params.length; i++) {
+                paramMap.put(PARAM + i, params[i]);
+            }
+        }
+        return paramMap;
+    }
+
+    public static Map<String, Object> toProblemParameters(String message, Map<String, Object> paramMap) {
+        Map<String, Object> parameters = new HashMap<>();
+        parameters.put("message", message);
+        parameters.put("params", paramMap);
+        return parameters;
+    }
+}
--- a/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/web/rest/errors/EmailAlreadyUsedException.java
+++ b/jhipster-6/bookstore-monolith/src/main/java/com/baeldung/jhipster6/web/rest/errors/EmailAlreadyUsedException.java
@ -0,0 +1,10 @@
+package com.baeldung.jhipster6.web.rest.errors;
+
+public class EmailAlreadyUsedException extends BadRequestAlertException {
+
+    private static final long serialVersionUID = 1L;
+
+    public EmailAlreadyUsedException() {
+        super(ErrorConstants.EMAIL_ALREADY_USED_TYPE, "Email is already in use!", "userManagement", "emailexists");
+    }
+}
--- a/Show More
+++ b/Show More
				`@ -0,0 +1 @@`
				`distributionUrl=https://repo.maven.apache.org/maven2/org/apache/maven/apache-maven/3.6.0/apache-maven-3.6.0-bin.zip`