BAEL-137 Intro do JHipster (#1427)

* refactor: Reorder tests without lambda

Moves inner implementations of Answer and ArgumentMatcher to the top of
the test classes.
Also changes the lambda expression to a regular "pre java 8" expression
in one of the tests.

Resolves: BAEL-632

* feat: Create basic Monolithic JHipster project

Commit just after creating a JHipster project, before making any modifications.

Resolves: BAEL-137

* chore: Change the artifactId and name of the project

From baeldung to jhipster-monolithic and JHipster Monolithic Application

Relates to: BAEL-137

* feat: Create entities Post and Comment

Relates to: BAEL-137

* feat: Fix Gatling configuration in pom.xml

Relates to: BAEL-137

* feat: Add files for Continuous Integration

Relates to: BAEL-137

* feat: Change pom.xml to conform to Baeldung standards

- moved the <properties> element to the bottom of the file
- excluded integration tests in the default surefire configuration
- added a new profile, called integration, and added the integration tests there
- added Java 8 in the <source> and <target> tags, under maven-compiler

solves: BAEL-137

* chore: Add jhipster module to parent pom

jhipster/.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,bower}.json]
+indent_style = space
+indent_size = 2

jhipster/.gitattributes

@@ -0,0 +1,22 @@
+# All text files should have the "lf" (Unix) line endings
+* text eol=lf
+
+# Explicitly declare text files you want to always be normalized and converted
+# to native line endings on checkout.
+*.java text
+*.js text
+*.css text
+*.html text
+
+# Denote all files that are truly binary and should not be modified.
+*.png binary
+*.jpg binary
+*.jar binary
+*.pdf binary
+*.eot binary
+*.ttf binary
+*.gzip binary
+*.gz binary
+*.ai binary
+*.eps binary
+*.swf binary

jhipster/.gitignore

@@ -0,0 +1,143 @@
+######################
+# Project Specific
+######################
+/src/main/webapp/content/css/main.css
+/target/www/**
+/src/test/javascript/coverage/
+/src/test/javascript/PhantomJS*/
+
+######################
+# Node
+######################
+/node/
+node_tmp/
+node_modules/
+npm-debug.log.*
+
+######################
+# 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
+
+######################
+# 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
+/.apt_generated/

jhipster/.gitlab-ci.yml

@@ -0,0 +1,56 @@
+
+cache:
+    key: "$CI_BUILD_REF_NAME"
+    paths:
+        - node_modules
+        - .maven
+stages:
+    - build
+    - test
+    - package
+
+before_script:
+    - export MAVEN_USER_HOME=`pwd`/.maven
+    - chmod +x mvnw
+    - ./mvnw com.github.eirslett:frontend-maven-plugin:install-node-and-npm -DnodeVersion=v6.10.0 -DnpmVersion=4.3.0
+    - ./mvnw com.github.eirslett:frontend-maven-plugin:npm
+
+maven-build:
+    stage: build
+    script: ./mvnw compile -Dmaven.repo.local=$MAVEN_USER_HOME
+
+maven-test:
+    stage: test
+    script:
+        - ./mvnw test -Dmaven.repo.local=$MAVEN_USER_HOME
+    artifacts:
+        paths:
+            - target/surefire-reports/*
+maven-front-test:
+    stage: test
+    script:
+        - ./mvnw com.github.eirslett:frontend-maven-plugin:npm -Dfrontend.yarn.arguments=test
+    artifacts:
+        paths:
+            - target/test-results/karma/*
+gatling-test:
+    stage: test
+    allow_failure: true
+    script:
+        - ./mvnw gatling:execute -Dmaven.repo.local=$MAVEN_USER_HOME
+    before_script:
+        - export MAVEN_USER_HOME=`pwd`/.maven
+        - chmod +x mvnw
+        - ./mvnw com.github.eirslett:frontend-maven-plugin:install-node-and-npm -DnodeVersion=v6.10.0 -DnpmVersion=4.3.0
+        - ./mvnw com.github.eirslett:frontend-maven-plugin:npm
+        - ./mvnw &
+    artifacts:
+        paths:
+            - target/gatling/*
+maven-package:
+    stage: package
+    script:
+        - ./mvnw package -Pprod -DskipTests -Dmaven.repo.local=$MAVEN_USER_HOME
+    artifacts:
+        paths:
+            - target/*.war

jhipster/.jhipster/Comment.json

@@ -0,0 +1,39 @@
+{
+    "fluentMethods": true,
+    "relationships": [
+        {
+            "relationshipName": "post",
+            "otherEntityName": "post",
+            "relationshipType": "many-to-one",
+            "relationshipValidateRules": [
+                "required"
+            ],
+            "otherEntityField": "title"
+        }
+    ],
+    "fields": [
+        {
+            "fieldName": "text",
+            "fieldType": "String",
+            "fieldValidateRules": [
+                "required",
+                "minlength",
+                "maxlength"
+            ],
+            "fieldValidateRulesMinlength": "10",
+            "fieldValidateRulesMaxlength": "100"
+        },
+        {
+            "fieldName": "creationDate",
+            "fieldType": "LocalDate",
+            "fieldValidateRules": [
+                "required"
+            ]
+        }
+    ],
+    "changelogDate": "20170316224021",
+    "dto": "no",
+    "service": "no",
+    "entityTableName": "comment",
+    "pagination": "infinite-scroll"
+}

jhipster/.jhipster/Post.json

@@ -0,0 +1,52 @@
+{
+    "fluentMethods": true,
+    "relationships": [
+        {
+            "relationshipName": "creator",
+            "otherEntityName": "user",
+            "relationshipType": "many-to-one",
+            "relationshipValidateRules": [
+                "required"
+            ],
+            "otherEntityField": "login",
+            "ownerSide": true,
+            "otherEntityRelationshipName": "post"
+        }
+    ],
+    "fields": [
+        {
+            "fieldName": "title",
+            "fieldType": "String",
+            "fieldValidateRules": [
+                "required",
+                "minlength",
+                "maxlength"
+            ],
+            "fieldValidateRulesMinlength": "10",
+            "fieldValidateRulesMaxlength": "100"
+        },
+        {
+            "fieldName": "content",
+            "fieldType": "String",
+            "fieldValidateRules": [
+                "required",
+                "minlength",
+                "maxlength"
+            ],
+            "fieldValidateRulesMinlength": "10",
+            "fieldValidateRulesMaxlength": "1000"
+        },
+        {
+            "fieldName": "creationDate",
+            "fieldType": "LocalDate",
+            "fieldValidateRules": [
+                "required"
+            ]
+        }
+    ],
+    "changelogDate": "20170316223211",
+    "dto": "no",
+    "service": "no",
+    "entityTableName": "post",
+    "pagination": "infinite-scroll"
+}

jhipster/.mvn/wrapper/maven-wrapper.properties

@@ -0,0 +1 @@
+distributionUrl=https://repo1.maven.org/maven2/org/apache/maven/apache-maven/3.3.9/apache-maven-3.3.9-bin.zip

jhipster/.travis.yml

@@ -0,0 +1,41 @@
+os:
+  - linux
+services:
+  - docker
+language: node_js
+node_js:
+  - "6.10.0"
+jdk:
+  - oraclejdk8
+sudo: false
+cache:
+  directories:
+    - node
+    - node_modules
+    - $HOME/.m2
+env:
+  global:
+    - NODE_VERSION=6.10.0
+    - SPRING_OUTPUT_ANSI_ENABLED=ALWAYS
+    - SPRING_JPA_SHOW_SQL=false
+before_install:
+  - jdk_switcher use oraclejdk8
+  - java -version
+  - sudo /etc/init.d/mysql stop
+  - sudo /etc/init.d/postgresql stop
+  - nvm install $NODE_VERSION
+  - npm install -g npm
+  - node -v
+  - npm -v
+install:
+  - npm install
+script:
+  - chmod +x mvnw
+  - ./mvnw clean test
+  - npm test
+  - ./mvnw package -Pprod -DskipTests
+notifications:
+  webhooks:
+    on_success: change  # options: [always|never|change] default: always
+    on_failure: always  # options: [always|never|change] default: always
+    on_start: false     # default: false

jhipster/.yo-rc.json

@@ -0,0 +1,36 @@
+{
+  "generator-jhipster": {
+    "jhipsterVersion": "4.0.8",
+    "baseName": "baeldung",
+    "packageName": "com.baeldung",
+    "packageFolder": "com/baeldung",
+    "serverPort": "8080",
+    "authenticationType": "jwt",
+    "hibernateCache": "ehcache",
+    "clusteredHttpSession": false,
+    "websocket": false,
+    "databaseType": "sql",
+    "devDatabaseType": "h2Disk",
+    "prodDatabaseType": "mysql",
+    "searchEngine": false,
+    "messageBroker": false,
+    "serviceDiscoveryType": false,
+    "buildTool": "maven",
+    "enableSocialSignIn": false,
+    "jwtSecretKey": "e1d4b69d3f953e3fa622121e882e6f459ca20ca4",
+    "clientFramework": "angular2",
+    "useSass": true,
+    "clientPackageManager": "npm",
+    "applicationType": "monolith",
+    "testFrameworks": [
+      "gatling",
+      "protractor"
+    ],
+    "jhiPrefix": "jhi",
+    "enableTranslation": true,
+    "nativeLanguage": "en",
+    "languages": [
+      "en"
+    ]
+  }
+}

jhipster/Jenkinsfile

@@ -0,0 +1,50 @@
+#!/usr/bin/env groovy
+
+node {
+    stage('checkout') {
+        checkout scm
+    }
+
+    stage('check java') {
+        sh "java -version"
+    }
+
+    stage('clean') {
+        sh "chmod +x mvnw"
+        sh "./mvnw clean"
+    }
+
+    stage('install tools') {
+        sh "./mvnw com.github.eirslett:frontend-maven-plugin:install-node-and-npm -DnodeVersion=v6.10.0 -DnpmVersion=4.3.0"
+    }
+
+    stage('npm install') {
+        sh "./mvnw com.github.eirslett:frontend-maven-plugin:npm"
+    }
+
+    stage('backend tests') {
+        try {
+            sh "./mvnw test"
+        } catch(err) {
+            throw err
+        } finally {
+            junit '**/target/surefire-reports/TEST-*.xml'
+        }
+    }
+
+    stage('frontend tests') {
+        try {
+            sh "./mvnw com.github.eirslett:frontend-maven-plugin:npm -Dfrontend.yarn.arguments=test"
+        } catch(err) {
+            throw err
+        } finally {
+            junit '**/target/test-results/karma/TESTS-*.xml'
+        }
+    }
+
+    stage('packaging') {
+        sh "./mvnw package -Pprod -DskipTests"
+        archiveArtifacts artifacts: '**/target/*.war', fingerprint: true
+    }
+
+}

jhipster/README.md

@@ -0,0 +1,153 @@
+# baeldung
+This application was generated using JHipster 4.0.8, you can find documentation and help at [https://jhipster.github.io/documentation-archive/v4.0.8](https://jhipster.github.io/documentation-archive/v4.0.8).
+
+## Development
+
+Before you can build this project, you must install and configure the following dependencies on your machine:
+
+1. [Node.js][]: We use Node to run a development web server and build the project.
+   Depending on your system, you can install Node either from source or as a pre-packaged bundle.
+
+After installing Node, you should be able to run the following command to install development tools.
+You will only need to run this command when dependencies change in [package.json](package.json).
+
+    npm install
+
+We use npm scripts and [Webpack][] as our build system.
+
+
+Run the following commands in two separate terminals to create a blissful development experience where your browser
+auto-refreshes when files change on your hard drive.
+
+    ./mvnw
+    npm start
+
+[Npm][] is also used to manage CSS and JavaScript dependencies used in this application. You can upgrade dependencies by
+specifying a newer version in [package.json](package.json). You can also run `npm update` and `npm install` to manage dependencies.
+Add the `help` flag on any command to see how you can use it. For example, `npm help update`.
+
+The `npm run` command will list all of the scripts available to run for this project.
+
+### Managing dependencies
+
+For example, to add [Leaflet][] library as a runtime dependency of your application, you would run following command:
+
+    npm install --save --save-exact leaflet
+
+To benefit from TypeScript type definitions from [DefinitelyTyped][] repository in development, you would run following command:
+
+    npm install --save-dev --save-exact @types/leaflet
+
+Then you would import the JS and CSS files specified in library's installation instructions so that [Webpack][] knows about them:
+
+Edit [src/main/webapp/app/vendor.ts](src/main/webapp/app/vendor.ts) file:
+~~~
+import 'leaflet/dist/leaflet.js';
+~~~
+
+Edit [src/main/webapp/content/css/vendor.css](src/main/webapp/content/css/vendor.css) file:
+~~~
+@import '~leaflet/dist/leaflet.css';
+~~~
+
+Note: there are still few other things remaining to do for Leaflet that we won't detail here.
+
+For further instructions on how to develop with JHipster, have a look at [Using JHipster in development][].
+
+### Using angular-cli
+
+You can also use [Angular CLI][] to generate some custom client code.
+
+For example, the following command:
+
+    ng generate component my-component
+
+will generate few files:
+
+    create src/main/webapp/app/my-component/my-component.component.html
+    create src/main/webapp/app/my-component/my-component.component.ts
+    update src/main/webapp/app/app.module.ts
+
+## Building for production
+
+To optimize the baeldung application for production, run:
+
+    ./mvnw -Pprod clean package
+
+This will concatenate and minify the client CSS and JavaScript files. It will also modify `index.html` so it references these new files.
+To ensure everything worked, run:
+
+    java -jar target/*.war
+
+Then navigate to [http://localhost:8080](http://localhost:8080) in your browser.
+
+Refer to [Using JHipster in production][] for more details.
+
+## Testing
+
+To launch your application's tests, run:
+
+    ./mvnw clean test
+
+### Client tests
+
+Unit tests are run by [Karma][] and written with [Jasmine][]. They're located in [src/test/javascript/](src/test/javascript/) and can be run with:
+
+    npm test
+
+UI end-to-end tests are powered by [Protractor][], which is built on top of WebDriverJS. They're located in [src/test/javascript/e2e](src/test/javascript/e2e)
+and can be run by starting Spring Boot in one terminal (`./mvnw spring-boot:run`) and running the tests (`gulp itest`) in a second one.
+### Other tests
+
+Performance tests are run by [Gatling][] and written in Scala. They're located in [src/test/gatling](src/test/gatling) and can be run with:
+
+    ./mvnw gatling:execute
+
+For more information, refer to the [Running tests page][].
+
+## Using Docker to simplify development (optional)
+
+You can use Docker to improve your JHipster development experience. A number of docker-compose configuration are available in the [src/main/docker](src/main/docker) folder to launch required third party services.
+For example, to start a mysql database in a docker container, run:
+
+    docker-compose -f src/main/docker/mysql.yml up -d
+
+To stop it and remove the container, run:
+
+    docker-compose -f src/main/docker/mysql.yml down
+
+You can also fully dockerize your application and all the services that it depends on.
+To achieve this, first build a docker image of your app by running:
+
+    ./mvnw package -Pprod docker:build
+
+Then run:
+
+    docker-compose -f src/main/docker/app.yml up -d
+
+For more information refer to [Using Docker and Docker-Compose][], this page also contains information on the docker-compose sub-generator (`yo jhipster:docker-compose`), which is able to generate docker configurations for one or several JHipster applications.
+
+## Continuous Integration (optional)
+
+To configure CI for your project, run the ci-cd sub-generator (`yo jhipster:ci-cd`), this will let you generate configuration files for a number of Continuous Integration systems. Consult the [Setting up Continuous Integration][] page for more information.
+
+[JHipster Homepage and latest documentation]: https://jhipster.github.io
+[JHipster 4.0.8 archive]: https://jhipster.github.io/documentation-archive/v4.0.8
+
+[Using JHipster in development]: https://jhipster.github.io/documentation-archive/v4.0.8/development/
+[Using Docker and Docker-Compose]: https://jhipster.github.io/documentation-archive/v4.0.8/docker-compose
+[Using JHipster in production]: https://jhipster.github.io/documentation-archive/v4.0.8/production/
+[Running tests page]: https://jhipster.github.io/documentation-archive/v4.0.8/running-tests/
+[Setting up Continuous Integration]: https://jhipster.github.io/documentation-archive/v4.0.8/setting-up-ci/
+
+[Gatling]: http://gatling.io/
+[Node.js]: https://nodejs.org/
+[Yarn]: https://yarnpkg.org/
+[Webpack]: https://webpack.github.io/
+[Angular CLI]: https://cli.angular.io/
+[BrowserSync]: http://www.browsersync.io/
+[Karma]: http://karma-runner.github.io/
+[Jasmine]: http://jasmine.github.io/2.0/introduction.html
+[Protractor]: https://angular.github.io/protractor/
+[Leaflet]: http://leafletjs.com/
+[DefinitelyTyped]: http://definitelytyped.org/

jhipster/angular-cli.json

@@ -0,0 +1,55 @@
+{
+  "project": {
+    "version": "1.0.0-beta.24",
+    "name": "baeldung"
+  },
+  "apps": [
+    {
+      "root": "src/main/webapp/",
+      "outDir": "target/www/app",
+      "assets": [
+        "content",
+        "favicon.ico"
+      ],
+      "index": "index.html",
+      "main": "app/app.main.ts",
+      "test": "",
+      "tsconfig": "../../../tsconfig.json",
+      "prefix": "jhi",
+      "mobile": false,
+      "styles": [
+        "content/css/main.css"
+      ],
+      "scripts": [],
+      "environments": {}
+    }
+  ],
+  "addons": [],
+  "packages": [],
+  "e2e": {
+    "protractor": {
+      "config": "src/test/javascript/protractor.conf.js"
+    }
+  },
+  "test": {
+    "karma": {
+      "config": "src/test/javascript/karma.conf.js"
+    }
+  },
+  "defaults": {
+    "styleExt": "css",
+    "prefixInterfaces": false,
+    "inline": {
+      "style": true,
+      "template": false
+    },
+    "spec": {
+      "class": false,
+      "component": false,
+      "directive": false,
+      "module": false,
+      "pipe": false,
+      "service": false
+    }
+  }
+}

jhipster/circle.yml

@@ -0,0 +1,25 @@
+machine:
+    services:
+        - docker
+    java:
+        version: oraclejdk8
+    node:
+        version: 6.10.0
+dependencies:
+    cache_directories:
+        - node
+        - node_modules
+        - ~/.m2
+    override:
+        - java -version
+        - npm install -g npm
+        - node -v
+        - npm -v
+        - java -version
+        - npm install
+test:
+    override:
+        - chmod +x mvnw
+        - ./mvnw clean test
+        - npm test
+        - ./mvnw package -Pprod -DskipTests

jhipster/mvnw

@@ -0,0 +1,233 @@
+#!/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.  $var _must_ be set to either true or false.
+cygwin=false;
+darwin=false;
+mingw=false
+case "`uname`" in
+  CYGWIN*) cygwin=true ;;
+  MINGW*) mingw=true;;
+  Darwin*) darwin=true
+           #
+           # Look for the Apple JDKs first to preserve the existing behaviour, and then look
+           # for the new JDKs provided by Oracle.
+           #
+           if [ -z "$JAVA_HOME" ] && [ -L /System/Library/Frameworks/JavaVM.framework/Versions/CurrentJDK ] ; then
+             #
+             # Apple JDKs
+             #
+             export JAVA_HOME=/System/Library/Frameworks/JavaVM.framework/Versions/CurrentJDK/Home
+           fi
+
+           if [ -z "$JAVA_HOME" ] && [ -L /System/Library/Java/JavaVirtualMachines/CurrentJDK ] ; then
+             #
+             # Apple JDKs
+             #
+             export JAVA_HOME=/System/Library/Java/JavaVirtualMachines/CurrentJDK/Contents/Home
+           fi
+
+           if [ -z "$JAVA_HOME" ] && [ -L "/Library/Java/JavaVirtualMachines/CurrentJDK" ] ; then
+             #
+             # Oracle JDKs
+             #
+             export JAVA_HOME=/Library/Java/JavaVirtualMachines/CurrentJDK/Contents/Home
+           fi
+
+           if [ -z "$JAVA_HOME" ] && [ -x "/usr/libexec/java_home" ]; then
+             #
+             # Apple JDKs
+             #
+             export JAVA_HOME=`/usr/libexec/java_home`
+           fi
+           ;;
+esac
+
+if [ -z "$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 Migwn, 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
+
+# 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 "$CLASSPATH"`
+fi
+
+# traverses directory structure from process work directory to filesystem root
+# first directory with .mvn subdirectory is considered project base directory
+find_maven_basedir() {
+  local basedir=$(pwd)
+  local wdir=$(pwd)
+  while [ "$wdir" != '/' ] ; do
+    if [ -d "$wdir"/.mvn ] ; then
+      basedir=$wdir
+      break
+    fi
+    wdir=$(cd "$wdir/.."; pwd)
+  done
+  echo "${basedir}"
+}
+
+# concatenates all lines of a file
+concat_lines() {
+  if [ -f "$1" ]; then
+    echo "$(tr -s '\n' ' ' < "$1")"
+  fi
+}
+
+export MAVEN_PROJECTBASEDIR=${MAVEN_BASEDIR:-$(find_maven_basedir)}
+MAVEN_OPTS="$(concat_lines "$MAVEN_PROJECTBASEDIR/.mvn/jvm.config") $MAVEN_OPTS"
+
+# Provide a "standardized" way to retrieve the CLI args that will
+# work with both Windows and non-Windows executions.
+MAVEN_CMD_LINE_ARGS="$MAVEN_CONFIG $@"
+export MAVEN_CMD_LINE_ARGS
+
+WRAPPER_LAUNCHER=org.apache.maven.wrapper.MavenWrapperMain
+
+exec "$JAVACMD" \
+  $MAVEN_OPTS \
+  -classpath "$MAVEN_PROJECTBASEDIR/.mvn/wrapper/maven-wrapper.jar" \
+  "-Dmaven.home=${M2_HOME}" "-Dmaven.multiModuleProjectDirectory=${MAVEN_PROJECTBASEDIR}" \
+  ${WRAPPER_LAUNCHER} "$@"

jhipster/mvnw.cmd

@@ -0,0 +1,145 @@
+@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 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
+
+set MAVEN_CMD_LINE_ARGS=%*
+
+@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="".\.mvn\wrapper\maven-wrapper.jar""
+set WRAPPER_LAUNCHER=org.apache.maven.wrapper.MavenWrapperMain
+
+%MAVEN_JAVA_EXE% %JVM_CONFIG_MAVEN_PROPS% %MAVEN_OPTS% %MAVEN_DEBUG_OPTS% -classpath %WRAPPER_JAR% "-Dmaven.multiModuleProjectDirectory=%MAVEN_PROJECTBASEDIR%" %WRAPPER_LAUNCHER% %MAVEN_CMD_LINE_ARGS%
+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%

jhipster/package.json

@@ -0,0 +1,112 @@
+{
+  "name": "baeldung",
+  "version": "0.0.0",
+  "description": "Description for baeldung",
+  "private": true,
+  "cacheDirectories": [
+    "node_modules"
+  ],
+  "dependencies": {
+    "@angular/common": "2.4.7",
+    "@angular/compiler": "2.4.7",
+    "@angular/core": "2.4.7",
+    "@angular/forms": "2.4.7",
+    "@angular/http": "2.4.7",
+    "@angular/platform-browser": "2.4.7",
+    "@angular/platform-browser-dynamic": "2.4.7",
+    "@angular/router": "3.4.7",
+    "@ng-bootstrap/ng-bootstrap": "1.0.0-alpha.20",
+    "angular2-infinite-scroll": "0.3.0",
+    "bootstrap": "4.0.0-alpha.6",
+    "font-awesome": "4.7.0",
+    "angular2-cookie": "1.2.6",
+    "core-js": "2.4.1",
+    "jquery": "3.1.1",
+    "ng-jhipster": "0.1.9",
+    "ng2-webstorage": "1.5.0",
+    "reflect-metadata": "0.1.9",
+    "rxjs": "5.1.0",
+    "swagger-ui": "2.2.10",
+    "tether": "1.4.0",
+    "zone.js": "0.7.6"
+  },
+  "devDependencies": {
+    "@angular/cli": "1.0.0-beta.28.3",
+    "@types/jasmine": "2.5.42",
+    "@types/node": "7.0.5",
+    "@types/selenium-webdriver": "2.53.39",
+    "add-asset-html-webpack-plugin": "1.0.2",
+    "angular2-template-loader": "0.6.2",
+    "awesome-typescript-loader": "3.0.7",
+    "browser-sync": "2.18.7",
+    "browser-sync-webpack-plugin": "1.1.4",
+    "codelyzer": "2.0.0",
+    "copy-webpack-plugin": "4.0.1",
+    "css-loader": "0.26.1",
+    "del": "2.2.2",
+    "event-stream": "3.3.4",
+    "exports-loader": "0.6.3",
+    "extract-text-webpack-plugin": "2.0.0-beta.5",
+    "file-loader": "0.10.0",
+    "generator-jhipster": "4.0.8",
+    "html-webpack-plugin": "2.28.0",
+    "image-webpack-loader": "3.2.0",
+    "jasmine-core": "2.5.2",
+    "jasmine-reporters": "2.2.0",
+    "karma": "1.4.1",
+    "karma-chrome-launcher": "2.0.0",
+    "karma-coverage": "1.1.1",
+    "karma-intl-shim": "1.0.3",
+    "karma-jasmine": "1.1.0",
+    "karma-junit-reporter": "1.2.0",
+    "karma-phantomjs-launcher": "1.0.2",
+    "karma-remap-istanbul": "0.6.0",
+    "karma-sourcemap-loader": "0.3.7",
+    "karma-webpack": "2.0.2",
+    "lazypipe": "1.0.1",
+    "lodash": "4.17.4",
+    "map-stream": "0.0.6",
+    "phantomjs-prebuilt": "2.1.14",
+    "protractor": "5.1.1",
+    "protractor-jasmine2-screenshot-reporter": "0.3.3",
+    "ts-node": "2.1.0",
+    "proxy-middleware": "0.15.0",
+    "raw-loader": "0.5.1",
+    "run-sequence": "1.2.2",
+    "sourcemap-istanbul-instrumenter-loader": "0.2.0",
+    "string-replace-webpack-plugin": "0.0.5",
+    "style-loader": "0.13.1",
+    "to-string-loader": "1.1.5",
+    "tslint": "4.4.2",
+    "tslint-loader": "3.4.1",
+    "typescript": "2.1.6",
+    "webpack": "2.2.1",
+    "webpack-dev-server": "2.3.0",
+    "webpack-merge": "2.6.1",
+    "webpack-visualizer-plugin": "0.1.10",
+    "write-file-webpack-plugin": "3.4.2",
+    "xml2js": "0.4.17",
+    "sass-loader": "5.0.1",
+    "node-sass": "4.5.0",
+    "postcss-loader": "1.3.0",
+    "yargs": "6.6.0"
+  },
+  "engines": {
+    "node": ">=6.9.0"
+  },
+  "scripts": {
+    "lint": "tslint 'src/main/webapp/app/**/*.ts' --force",
+    "lint:fix": "tslint 'src/main/webapp/app/**/*.ts' --fix --force",
+    "tsc": "tsc",
+    "tsc:w": "tsc -w",
+    "start": "npm run webpack:dev",
+    "webpack:build": "webpack --config webpack/webpack.vendor.js && webpack --config webpack/webpack.dev.js",
+    "webpack:build:dev": "webpack --config webpack/webpack.dev.js",
+    "webpack:dev": "webpack-dev-server --config webpack/webpack.dev.js  --progress --inline --hot --profile --port=9060",
+    "webpack:prod": "npm test && webpack -p --config webpack/webpack.vendor.js && webpack -p --config webpack/webpack.prod.js",
+    "test": "npm run lint && karma start src/test/javascript/karma.conf.js",
+    "test:watch": "karma start --watch",
+    "e2e": "protractor src/test/javascript/protractor.conf.js",
+    "postinstall": "webdriver-manager update && npm run webpack:build"
+  }
+}

jhipster/postcss.config.js

@@ -0,0 +1,3 @@
+module.exports = {
+    plugins: []
+}

jhipster/src/main/docker/Dockerfile

@@ -0,0 +1,13 @@
+FROM openjdk:8-jre-alpine
+
+ENV SPRING_OUTPUT_ANSI_ENABLED=ALWAYS \
+    JHIPSTER_SLEEP=0
+
+# add directly the war
+ADD *.war /app.war
+
+VOLUME /tmp
+EXPOSE 8080
+CMD echo "The application will start in ${JHIPSTER_SLEEP}s..." && \
+    sleep ${JHIPSTER_SLEEP} && \
+    java -Djava.security.egd=file:/dev/./urandom -jar /app.war

jhipster/src/main/docker/app.yml

@@ -0,0 +1,14 @@
+version: '2'
+services:
+    baeldung-app:
+        image: baeldung
+        environment:
+            - SPRING_PROFILES_ACTIVE=prod,swagger
+            - SPRING_DATASOURCE_URL=jdbc:mysql://baeldung-mysql:3306/baeldung?useUnicode=true&characterEncoding=utf8&useSSL=false
+            - JHIPSTER_SLEEP=10 # gives time for the database to boot before the application
+        ports:
+            - 8080:8080
+    baeldung-mysql:
+        extends:
+            file: mysql.yml
+            service: baeldung-mysql

jhipster/src/main/docker/mysql.yml

@@ -0,0 +1,13 @@
+version: '2'
+services:
+    baeldung-mysql:
+        image: mysql:5.7.13
+        # volumes:
+        #     - ~/volumes/jhipster/baeldung/mysql/:/var/lib/mysql/
+        environment:
+            - MYSQL_USER=root
+            - MYSQL_ALLOW_EMPTY_PASSWORD=yes
+            - MYSQL_DATABASE=baeldung
+        ports:
+            - 3306:3306
+        command: mysqld --lower_case_table_names=1 --skip-ssl --character_set_server=utf8

jhipster/src/main/docker/sonar.yml

@@ -0,0 +1,7 @@
+version: '2'
+services:
+    baeldung-sonar:
+        image: sonarqube:6.2-alpine
+        ports:
+            - 9000:9000
+            - 9092:9092

jhipster/src/main/java/com/baeldung/ApplicationWebXml.java

@@ -0,0 +1,21 @@
+package com.baeldung;
+
+import com.baeldung.config.DefaultProfileUtil;
+import org.springframework.boot.builder.SpringApplicationBuilder;
+import org.springframework.boot.web.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(BaeldungApp.class);
+    }
+}

jhipster/src/main/java/com/baeldung/BaeldungApp.java

@@ -0,0 +1,84 @@
+package com.baeldung;
+
+import com.baeldung.config.ApplicationProperties;
+import com.baeldung.config.DefaultProfileUtil;
+
+import io.github.jhipster.config.JHipsterConstants;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.actuate.autoconfigure.*;
+import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
+import org.springframework.boot.autoconfigure.liquibase.LiquibaseProperties;
+import org.springframework.boot.context.properties.EnableConfigurationProperties;
+import org.springframework.context.annotation.ComponentScan;
+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;
+
+@ComponentScan
+@EnableAutoConfiguration(exclude = {MetricFilterAutoConfiguration.class, MetricRepositoryAutoConfiguration.class})
+@EnableConfigurationProperties({LiquibaseProperties.class, ApplicationProperties.class})
+public class BaeldungApp {
+
+    private static final Logger log = LoggerFactory.getLogger(BaeldungApp.class);
+
+    private final Environment env;
+
+    public BaeldungApp(Environment env) {
+        this.env = env;
+    }
+
+    /**
+     * Initializes baeldung.
+     * <p>
+     * Spring profiles can be configured with a program arguments --spring.profiles.active=your-active-profile
+     * <p>
+     * You can find more information on how profiles work with JHipster on <a href="http://jhipster.github.io/profiles/">http://jhipster.github.io/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
+     * @throws UnknownHostException if the local host name could not be resolved into an address
+     */
+    public static void main(String[] args) throws UnknownHostException {
+        SpringApplication app = new SpringApplication(BaeldungApp.class);
+        DefaultProfileUtil.addDefaultProfile(app);
+        Environment env = app.run(args).getEnvironment();
+        String protocol = "http";
+        if (env.getProperty("server.ssl.key-store") != null) {
+            protocol = "https";
+        }
+        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,
+            env.getProperty("server.port"),
+            protocol,
+            InetAddress.getLocalHost().getHostAddress(),
+            env.getProperty("server.port"),
+            env.getActiveProfiles());
+    }
+}

jhipster/src/main/java/com/baeldung/aop/logging/LoggingAspect.java

@@ -0,0 +1,79 @@
+package com.baeldung.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(com.baeldung.repository..*) || within(com.baeldung.service..*) || within(com.baeldung.web.rest..*)")
+    public void loggingPointcut() {
+        // Method is empty as this is just a Pointcut, the implementations are in the advices.
+    }
+
+    /**
+     * Advice that logs methods throwing exceptions.
+     */
+    @AfterThrowing(pointcut = "loggingPointcut()", 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.
+     */
+    @Around("loggingPointcut()")
+    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;
+        }
+    }
+}

jhipster/src/main/java/com/baeldung/config/ApplicationProperties.java

@@ -0,0 +1,15 @@
+package com.baeldung.config;
+
+import org.springframework.boot.context.properties.ConfigurationProperties;
+
+/**
+ * Properties specific to JHipster.
+ *
+ * <p>
+ *     Properties are configured in the application.yml file.
+ * </p>
+ */
+@ConfigurationProperties(prefix = "application", ignoreUnknownFields = false)
+public class ApplicationProperties {
+
+}

jhipster/src/main/java/com/baeldung/config/AsyncConfiguration.java

@@ -0,0 +1,46 @@
+package com.baeldung.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 java.util.concurrent.Executor;
+
+@Configuration
+@EnableAsync
+@EnableScheduling
+public class AsyncConfiguration implements AsyncConfigurer {
+
+    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("baeldung-Executor-");
+        return new ExceptionHandlingAsyncTaskExecutor(executor);
+    }
+
+    @Override
+    public AsyncUncaughtExceptionHandler getAsyncUncaughtExceptionHandler() {
+        return new SimpleAsyncUncaughtExceptionHandler();
+    }
+}

jhipster/src/main/java/com/baeldung/config/CacheConfiguration.java

@@ -0,0 +1,48 @@
+package com.baeldung.config;
+
+import io.github.jhipster.config.JHipsterProperties;
+import org.ehcache.config.builders.CacheConfigurationBuilder;
+import org.ehcache.config.builders.ResourcePoolsBuilder;
+import org.ehcache.expiry.Duration;
+import org.ehcache.expiry.Expirations;
+import org.ehcache.jsr107.Eh107Configuration;
+
+import java.util.concurrent.TimeUnit;
+
+import org.springframework.boot.autoconfigure.AutoConfigureAfter;
+import org.springframework.boot.autoconfigure.AutoConfigureBefore;
+import org.springframework.boot.autoconfigure.cache.JCacheManagerCustomizer;
+import org.springframework.cache.annotation.EnableCaching;
+import org.springframework.context.annotation.*;
+
+@Configuration
+@EnableCaching
+@AutoConfigureAfter(value = { MetricsConfiguration.class })
+@AutoConfigureBefore(value = { WebConfigurer.class, DatabaseConfiguration.class })
+public class CacheConfiguration {
+
+    private final javax.cache.configuration.Configuration<Object, Object> jcacheConfiguration;
+
+    public CacheConfiguration(JHipsterProperties jHipsterProperties) {
+        JHipsterProperties.Cache.Ehcache ehcache =
+            jHipsterProperties.getCache().getEhcache();
+
+        jcacheConfiguration = Eh107Configuration.fromEhcacheCacheConfiguration(
+            CacheConfigurationBuilder.newCacheConfigurationBuilder(Object.class, Object.class,
+                ResourcePoolsBuilder.heap(ehcache.getMaxEntries()))
+                .withExpiry(Expirations.timeToLiveExpiration(Duration.of(ehcache.getTimeToLiveSeconds(), TimeUnit.SECONDS)))
+                .build());
+    }
+
+    @Bean
+    public JCacheManagerCustomizer cacheManagerCustomizer() {
+        return cm -> {
+            cm.createCache(com.baeldung.domain.User.class.getName(), jcacheConfiguration);
+            cm.createCache(com.baeldung.domain.Authority.class.getName(), jcacheConfiguration);
+            cm.createCache(com.baeldung.domain.User.class.getName() + ".authorities", jcacheConfiguration);
+            cm.createCache(com.baeldung.domain.Post.class.getName(), jcacheConfiguration);
+            cm.createCache(com.baeldung.domain.Comment.class.getName(), jcacheConfiguration);
+            // jhipster-needle-ehcache-add-entry
+        };
+    }
+}

jhipster/src/main/java/com/baeldung/config/CloudDatabaseConfiguration.java

@@ -0,0 +1,23 @@
+package com.baeldung.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;
+
+@Configuration
+@Profile(JHipsterConstants.SPRING_PROFILE_CLOUD)
+public class CloudDatabaseConfiguration extends AbstractCloudConfig {
+
+    private final Logger log = LoggerFactory.getLogger(CloudDatabaseConfiguration.class);
+
+    @Bean
+    public DataSource dataSource() {
+        log.info("Configuring JDBC datasource from a cloud provider");
+        return connectionFactory().dataSource();
+    }
+}

jhipster/src/main/java/com/baeldung/config/Constants.java

@@ -0,0 +1,16 @@
+package com.baeldung.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";
+
+    private Constants() {
+    }
+}

jhipster/src/main/java/com/baeldung/config/DatabaseConfiguration.java

@@ -0,0 +1,75 @@
+package com.baeldung.config;
+
+import io.github.jhipster.config.JHipsterConstants;
+import io.github.jhipster.config.liquibase.AsyncSpringLiquibase;
+
+import com.fasterxml.jackson.datatype.hibernate5.Hibernate5Module;
+import liquibase.integration.spring.SpringLiquibase;
+import org.h2.tools.Server;
+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.context.annotation.Profile;
+import org.springframework.core.env.Environment;
+import org.springframework.core.task.TaskExecutor;
+import org.springframework.data.jpa.repository.config.EnableJpaAuditing;
+import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
+import org.springframework.transaction.annotation.EnableTransactionManagement;
+
+import javax.sql.DataSource;
+import java.sql.SQLException;
+
+@Configuration
+@EnableJpaRepositories("com.baeldung.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 Server h2TCPServer() throws SQLException {
+        return Server.createTcpServer("-tcp","-tcpAllowOthers");
+    }
+
+    @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());
+        if (env.acceptsProfiles(JHipsterConstants.SPRING_PROFILE_NO_LIQUIBASE)) {
+            liquibase.setShouldRun(false);
+        } else {
+            liquibase.setShouldRun(liquibaseProperties.isEnabled());
+            log.debug("Configuring Liquibase");
+        }
+        return liquibase;
+    }
+
+    @Bean
+    public Hibernate5Module hibernate5Module() {
+        return new Hibernate5Module();
+    }
+}

jhipster/src/main/java/com/baeldung/config/DateTimeFormatConfiguration.java

@@ -0,0 +1,17 @@
+package com.baeldung.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.WebMvcConfigurerAdapter;
+
+@Configuration
+public class DateTimeFormatConfiguration extends WebMvcConfigurerAdapter {
+
+    @Override
+    public void addFormatters(FormatterRegistry registry) {
+        DateTimeFormatterRegistrar registrar = new DateTimeFormatterRegistrar();
+        registrar.setUseIsoFormat(true);
+        registrar.registerFormatters(registry);
+    }
+}

jhipster/src/main/java/com/baeldung/config/DefaultProfileUtil.java

@@ -0,0 +1,48 @@
+package com.baeldung.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.
+     */
+    public static String[] getActiveProfiles(Environment env) {
+        String[] profiles = env.getActiveProfiles();
+        if (profiles.length == 0) {
+            return env.getDefaultProfiles();
+        }
+        return profiles;
+    }
+}

jhipster/src/main/java/com/baeldung/config/LocaleConfiguration.java

@@ -0,0 +1,35 @@
+package com.baeldung.config;
+
+import io.github.jhipster.config.locale.AngularCookieLocaleResolver;
+
+import org.springframework.context.EnvironmentAware;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.core.env.Environment;
+import org.springframework.web.servlet.LocaleResolver;
+import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
+import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;
+import org.springframework.web.servlet.i18n.LocaleChangeInterceptor;
+
+@Configuration
+public class LocaleConfiguration extends WebMvcConfigurerAdapter implements EnvironmentAware {
+
+    @Override
+    public void setEnvironment(Environment environment) {
+        // unused
+    }
+
+    @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);
+    }
+}

jhipster/src/main/java/com/baeldung/config/LoggingAspectConfiguration.java

@@ -0,0 +1,19 @@
+package com.baeldung.config;
+
+import com.baeldung.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);
+    }
+}

jhipster/src/main/java/com/baeldung/config/LoggingConfiguration.java

@@ -0,0 +1,109 @@
+package com.baeldung.config;
+
+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.spi.LoggerContextListener;
+import ch.qos.logback.core.spi.ContextAwareBase;
+import net.logstash.logback.appender.LogstashSocketAppender;
+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 final Logger log = LoggerFactory.getLogger(LoggingConfiguration.class);
+
+    private LoggerContext context = (LoggerContext) LoggerFactory.getILoggerFactory();
+
+    @Value("${spring.application.name}")
+    private String appName;
+
+    @Value("${server.port}")
+    private String serverPort;
+
+    private final JHipsterProperties jHipsterProperties;
+
+    public LoggingConfiguration(JHipsterProperties jHipsterProperties) {
+        this.jHipsterProperties = jHipsterProperties;
+        if (jHipsterProperties.getLogging().getLogstash().isEnabled()) {
+            addLogstashAppender(context);
+
+            // Add context listener
+            LogbackLoggerContextListener loggerContextListener = new LogbackLoggerContextListener();
+            loggerContextListener.setContext(context);
+            context.addListener(loggerContextListener);
+        }
+    }
+
+    public void addLogstashAppender(LoggerContext context) {
+        log.info("Initializing Logstash logging");
+
+        LogstashSocketAppender logstashAppender = new LogstashSocketAppender();
+        logstashAppender.setName("LOGSTASH");
+        logstashAppender.setContext(context);
+        String customFields = "{\"app_name\":\"" + appName + "\",\"app_port\":\"" + serverPort + "\"}";
+
+        // Set the Logstash appender config from JHipster properties
+        logstashAppender.setSyslogHost(jHipsterProperties.getLogging().getLogstash().getHost());
+        logstashAppender.setPort(jHipsterProperties.getLogging().getLogstash().getPort());
+        logstashAppender.setCustomFields(customFields);
+
+        // Limit the maximum length of the forwarded stacktrace so that it won't exceed the 8KB UDP limit of logstash
+        ShortenedThrowableConverter throwableConverter = new ShortenedThrowableConverter();
+        throwableConverter.setMaxLength(7500);
+        throwableConverter.setRootCauseFirst(true);
+        logstashAppender.setThrowableConverter(throwableConverter);
+
+        logstashAppender.start();
+
+        // Wrap the appender in an Async appender for performance
+        AsyncAppender asyncLogstashAppender = new AsyncAppender();
+        asyncLogstashAppender.setContext(context);
+        asyncLogstashAppender.setName("ASYNC_LOGSTASH");
+        asyncLogstashAppender.setQueueSize(jHipsterProperties.getLogging().getLogstash().getQueueSize());
+        asyncLogstashAppender.addAppender(logstashAppender);
+        asyncLogstashAppender.start();
+
+        context.getLogger("ROOT").addAppender(asyncLogstashAppender);
+    }
+
+    /**
+     * 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.
+        }
+    }
+
+}

jhipster/src/main/java/com/baeldung/config/MetricsConfiguration.java

@@ -0,0 +1,94 @@
+package com.baeldung.config;
+
+import io.github.jhipster.config.JHipsterProperties;
+import io.github.jhipster.config.jcache.JCacheGaugeSet;
+
+import com.codahale.metrics.JmxReporter;
+import com.codahale.metrics.MetricRegistry;
+import com.codahale.metrics.Slf4jReporter;
+import com.codahale.metrics.health.HealthCheckRegistry;
+import com.codahale.metrics.jvm.*;
+import com.ryantenney.metrics.spring.config.annotation.EnableMetrics;
+import com.ryantenney.metrics.spring.config.annotation.MetricsConfigurerAdapter;
+import com.zaxxer.hikari.HikariDataSource;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.context.annotation.*;
+
+import javax.annotation.PostConstruct;
+import java.lang.management.ManagementFactory;
+import java.util.concurrent.TimeUnit;
+
+@Configuration
+@EnableMetrics(proxyTargetClass = true)
+public class MetricsConfiguration extends MetricsConfigurerAdapter {
+
+    private static final String PROP_METRIC_REG_JVM_MEMORY = "jvm.memory";
+    private static final String PROP_METRIC_REG_JVM_GARBAGE = "jvm.garbage";
+    private static final String PROP_METRIC_REG_JVM_THREADS = "jvm.threads";
+    private static final String PROP_METRIC_REG_JVM_FILES = "jvm.files";
+    private static final String PROP_METRIC_REG_JVM_BUFFERS = "jvm.buffers";
+
+    private static final String PROP_METRIC_REG_JCACHE_STATISTICS = "jcache.statistics";
+    private final Logger log = LoggerFactory.getLogger(MetricsConfiguration.class);
+
+    private MetricRegistry metricRegistry = new MetricRegistry();
+
+    private HealthCheckRegistry healthCheckRegistry = new HealthCheckRegistry();
+
+    private final JHipsterProperties jHipsterProperties;
+
+    private HikariDataSource hikariDataSource;
+
+    public MetricsConfiguration(JHipsterProperties jHipsterProperties) {
+        this.jHipsterProperties = jHipsterProperties;
+    }
+
+    @Autowired(required = false)
+    public void setHikariDataSource(HikariDataSource hikariDataSource) {
+        this.hikariDataSource = hikariDataSource;
+    }
+
+    @Override
+    @Bean
+    public MetricRegistry getMetricRegistry() {
+        return metricRegistry;
+    }
+
+    @Override
+    @Bean
+    public HealthCheckRegistry getHealthCheckRegistry() {
+        return healthCheckRegistry;
+    }
+
+    @PostConstruct
+    public void init() {
+        log.debug("Registering JVM gauges");
+        metricRegistry.register(PROP_METRIC_REG_JVM_MEMORY, new MemoryUsageGaugeSet());
+        metricRegistry.register(PROP_METRIC_REG_JVM_GARBAGE, new GarbageCollectorMetricSet());
+        metricRegistry.register(PROP_METRIC_REG_JVM_THREADS, new ThreadStatesGaugeSet());
+        metricRegistry.register(PROP_METRIC_REG_JVM_FILES, new FileDescriptorRatioGauge());
+        metricRegistry.register(PROP_METRIC_REG_JVM_BUFFERS, new BufferPoolMetricSet(ManagementFactory.getPlatformMBeanServer()));
+
+        metricRegistry.register(PROP_METRIC_REG_JCACHE_STATISTICS, new JCacheGaugeSet());
+        if (hikariDataSource != null) {
+            log.debug("Monitoring the datasource");
+            hikariDataSource.setMetricRegistry(metricRegistry);
+        }
+        if (jHipsterProperties.getMetrics().getJmx().isEnabled()) {
+            log.debug("Initializing Metrics JMX reporting");
+            JmxReporter jmxReporter = JmxReporter.forRegistry(metricRegistry).build();
+            jmxReporter.start();
+        }
+        if (jHipsterProperties.getMetrics().getLogs().isEnabled()) {
+            log.info("Initializing Metrics Log reporting");
+            final Slf4jReporter reporter = Slf4jReporter.forRegistry(metricRegistry)
+                .outputTo(LoggerFactory.getLogger("metrics"))
+                .convertRatesTo(TimeUnit.SECONDS)
+                .convertDurationsTo(TimeUnit.MILLISECONDS)
+                .build();
+            reporter.start(jHipsterProperties.getMetrics().getLogs().getReportFrequency(), TimeUnit.SECONDS);
+        }
+    }
+}

jhipster/src/main/java/com/baeldung/config/SecurityConfiguration.java

@@ -0,0 +1,127 @@
+package com.baeldung.config;
+
+import com.baeldung.security.*;
+import com.baeldung.security.jwt.*;
+
+import io.github.jhipster.security.*;
+
+import org.springframework.beans.factory.BeanInitializationException;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.http.HttpMethod;
+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.data.repository.query.SecurityEvaluationContextExtension;
+import org.springframework.security.web.authentication.UsernamePasswordAuthenticationFilter;
+import org.springframework.web.filter.CorsFilter;
+
+import javax.annotation.PostConstruct;
+
+@Configuration
+@EnableWebSecurity
+@EnableGlobalMethodSecurity(prePostEnabled = true, securedEnabled = true)
+public class SecurityConfiguration extends WebSecurityConfigurerAdapter {
+
+    private final AuthenticationManagerBuilder authenticationManagerBuilder;
+
+    private final UserDetailsService userDetailsService;
+
+    private final TokenProvider tokenProvider;
+
+    private final CorsFilter corsFilter;
+
+    public SecurityConfiguration(AuthenticationManagerBuilder authenticationManagerBuilder, UserDetailsService userDetailsService,
+            TokenProvider tokenProvider,
+        CorsFilter corsFilter) {
+
+        this.authenticationManagerBuilder = authenticationManagerBuilder;
+        this.userDetailsService = userDetailsService;
+        this.tokenProvider = tokenProvider;
+        this.corsFilter = corsFilter;
+    }
+
+    @PostConstruct
+    public void init() {
+        try {
+            authenticationManagerBuilder
+                .userDetailsService(userDetailsService)
+                    .passwordEncoder(passwordEncoder());
+        } catch (Exception e) {
+            throw new BeanInitializationException("Security configuration failed", e);
+        }
+    }
+
+    @Bean
+    public Http401UnauthorizedEntryPoint http401UnauthorizedEntryPoint() {
+        return new Http401UnauthorizedEntryPoint();
+    }
+
+    @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("/bower_components/**")
+            .antMatchers("/i18n/**")
+            .antMatchers("/content/**")
+            .antMatchers("/swagger-ui/index.html")
+            .antMatchers("/test/**")
+            .antMatchers("/h2-console/**");
+    }
+
+    @Override
+    protected void configure(HttpSecurity http) throws Exception {
+        http
+            .addFilterBefore(corsFilter, UsernamePasswordAuthenticationFilter.class)
+            .exceptionHandling()
+            .authenticationEntryPoint(http401UnauthorizedEntryPoint())
+        .and()
+            .csrf()
+            .disable()
+            .headers()
+            .frameOptions()
+            .disable()
+        .and()
+            .sessionManagement()
+            .sessionCreationPolicy(SessionCreationPolicy.STATELESS)
+        .and()
+            .authorizeRequests()
+            .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/profile-info").permitAll()
+            .antMatchers("/api/**").authenticated()
+            .antMatchers("/management/health").permitAll()
+            .antMatchers("/management/**").hasAuthority(AuthoritiesConstants.ADMIN)
+            .antMatchers("/v2/api-docs/**").permitAll()
+            .antMatchers("/swagger-resources/configuration/ui").permitAll()
+            .antMatchers("/swagger-ui/index.html").hasAuthority(AuthoritiesConstants.ADMIN)
+        .and()
+            .apply(securityConfigurerAdapter());
+
+    }
+
+    private JWTConfigurer securityConfigurerAdapter() {
+        return new JWTConfigurer(tokenProvider);
+    }
+
+    @Bean
+    public SecurityEvaluationContextExtension securityEvaluationContextExtension() {
+        return new SecurityEvaluationContextExtension();
+    }
+}

jhipster/src/main/java/com/baeldung/config/ThymeleafConfiguration.java

@@ -0,0 +1,26 @@
+package com.baeldung.config;
+
+import org.apache.commons.lang3.CharEncoding;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.context.annotation.*;
+import org.thymeleaf.templateresolver.ClassLoaderTemplateResolver;
+
+@Configuration
+public class ThymeleafConfiguration {
+
+    @SuppressWarnings("unused")
+    private final Logger log = LoggerFactory.getLogger(ThymeleafConfiguration.class);
+
+    @Bean
+    @Description("Thymeleaf template resolver serving HTML 5 emails")
+    public ClassLoaderTemplateResolver emailTemplateResolver() {
+        ClassLoaderTemplateResolver emailTemplateResolver = new ClassLoaderTemplateResolver();
+        emailTemplateResolver.setPrefix("mails/");
+        emailTemplateResolver.setSuffix(".html");
+        emailTemplateResolver.setTemplateMode("HTML5");
+        emailTemplateResolver.setCharacterEncoding(CharEncoding.UTF_8);
+        emailTemplateResolver.setOrder(1);
+        return emailTemplateResolver;
+    }
+}

jhipster/src/main/java/com/baeldung/config/WebConfigurer.java

@@ -0,0 +1,186 @@
+package com.baeldung.config;
+
+import io.github.jhipster.config.JHipsterConstants;
+import io.github.jhipster.config.JHipsterProperties;
+import io.github.jhipster.web.filter.CachingHttpHeadersFilter;
+
+import com.codahale.metrics.MetricRegistry;
+import com.codahale.metrics.servlet.InstrumentedFilter;
+import com.codahale.metrics.servlets.MetricsServlet;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.context.embedded.*;
+import org.springframework.boot.context.embedded.undertow.UndertowEmbeddedServletContainerFactory;
+import io.undertow.UndertowOptions;
+import org.springframework.boot.web.servlet.ServletContextInitializer;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.core.env.Environment;
+import org.springframework.web.cors.CorsConfiguration;
+import org.springframework.web.cors.UrlBasedCorsConfigurationSource;
+import org.springframework.web.filter.CorsFilter;
+
+import java.io.File;
+import java.nio.file.Paths;
+import java.util.*;
+import javax.servlet.*;
+
+/**
+ * Configuration of web application with Servlet 3.0 APIs.
+ */
+@Configuration
+public class WebConfigurer implements ServletContextInitializer, EmbeddedServletContainerCustomizer {
+
+    private final Logger log = LoggerFactory.getLogger(WebConfigurer.class);
+
+    private final Environment env;
+
+    private final JHipsterProperties jHipsterProperties;
+
+    private MetricRegistry metricRegistry;
+
+    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);
+        initMetrics(servletContext, disps);
+        if (env.acceptsProfiles(JHipsterConstants.SPRING_PROFILE_PRODUCTION)) {
+            initCachingHttpHeadersFilter(servletContext, disps);
+        }
+        if (env.acceptsProfiles(JHipsterConstants.SPRING_PROFILE_DEVELOPMENT)) {
+            initH2Console(servletContext);
+        }
+        log.info("Web application fully configured");
+    }
+
+    /**
+     * Customize the Servlet engine: Mime types, the document root, the cache.
+     */
+    @Override
+    public void customize(ConfigurableEmbeddedServletContainer container) {
+        MimeMappings mappings = new MimeMappings(MimeMappings.DEFAULT);
+        // IE issue, see https://github.com/jhipster/generator-jhipster/pull/711
+        mappings.add("html", "text/html;charset=utf-8");
+        // CloudFoundry issue, see https://github.com/cloudfoundry/gorouter/issues/64
+        mappings.add("json", "text/html;charset=utf-8");
+        container.setMimeMappings(mappings);
+        // When running in an IDE or with ./mvnw spring-boot:run, set location of the static web assets.
+        setLocationForStaticAssets(container);
+
+        /*
+         * Enable HTTP/2 for Undertow - https://twitter.com/ankinson/status/829256167700492288
+         * HTTP/2 requires HTTPS, so HTTP requests will fallback to HTTP/1.1.
+         * See the JHipsterProperties class and your application-*.yml configuration files
+         * for more information.
+         */
+        if (jHipsterProperties.getHttp().getVersion().equals(JHipsterProperties.Http.Version.V_2_0) &&
+            container instanceof UndertowEmbeddedServletContainerFactory) {
+
+            ((UndertowEmbeddedServletContainerFactory) container)
+                .addBuilderCustomizers(builder ->
+                    builder.setServerOption(UndertowOptions.ENABLE_HTTP2, true));
+        }
+    }
+
+    private void setLocationForStaticAssets(ConfigurableEmbeddedServletContainer container) {
+        File root;
+        String prefixPath = resolvePathPrefix();
+        root = new File(prefixPath + "target/www/");
+        if (root.exists() && root.isDirectory()) {
+            container.setDocumentRoot(root);
+        }
+    }
+
+    /**
+     *  Resolve path prefix to static resources.
+     */
+    private String resolvePathPrefix() {
+        String 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, "/content/*");
+        cachingHttpHeadersFilter.addMappingForUrlPatterns(disps, true, "/app/*");
+        cachingHttpHeadersFilter.setAsyncSupported(true);
+    }
+
+    /**
+     * Initializes Metrics.
+     */
+    private void initMetrics(ServletContext servletContext, EnumSet<DispatcherType> disps) {
+        log.debug("Initializing Metrics registries");
+        servletContext.setAttribute(InstrumentedFilter.REGISTRY_ATTRIBUTE,
+            metricRegistry);
+        servletContext.setAttribute(MetricsServlet.METRICS_REGISTRY,
+            metricRegistry);
+
+        log.debug("Registering Metrics Filter");
+        FilterRegistration.Dynamic metricsFilter = servletContext.addFilter("webappMetricsFilter",
+            new InstrumentedFilter());
+
+        metricsFilter.addMappingForUrlPatterns(disps, true, "/*");
+        metricsFilter.setAsyncSupported(true);
+
+        log.debug("Registering Metrics Servlet");
+        ServletRegistration.Dynamic metricsAdminServlet =
+            servletContext.addServlet("metricsServlet", new MetricsServlet());
+
+        metricsAdminServlet.addMapping("/management/metrics/*");
+        metricsAdminServlet.setAsyncSupported(true);
+        metricsAdminServlet.setLoadOnStartup(2);
+    }
+
+    @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("/v2/api-docs", config);
+        }
+        return new CorsFilter(source);
+    }
+
+    /**
+     * Initializes H2 console.
+     */
+    private void initH2Console(ServletContext servletContext) {
+        log.debug("Initialize H2 console");
+        ServletRegistration.Dynamic h2ConsoleServlet = servletContext.addServlet("H2Console", new org.h2.server.web.WebServlet());
+        h2ConsoleServlet.addMapping("/h2-console/*");
+        h2ConsoleServlet.setInitParameter("-properties", "src/main/resources/");
+        h2ConsoleServlet.setLoadOnStartup(1);
+    }
+
+    @Autowired(required = false)
+    public void setMetricRegistry(MetricRegistry metricRegistry) {
+        this.metricRegistry = metricRegistry;
+    }
+}

jhipster/src/main/java/com/baeldung/config/audit/AuditEventConverter.java

@@ -0,0 +1,91 @@
+package com.baeldung.config.audit;
+
+import com.baeldung.domain.PersistentAuditEvent;
+
+import org.springframework.boot.actuate.audit.AuditEvent;
+import org.springframework.security.web.authentication.WebAuthenticationDetails;
+import org.springframework.stereotype.Component;
+
+import java.time.Instant;
+import java.time.ZoneId;
+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) {
+        Instant instant = persistentAuditEvent.getAuditEventDate().atZone(ZoneId.systemDefault()).toInstant();
+        return new AuditEvent(Date.from(instant), 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()) {
+                Object object = entry.getValue();
+
+                // Extract the data that will be saved.
+                if (object instanceof WebAuthenticationDetails) {
+                    WebAuthenticationDetails authenticationDetails = (WebAuthenticationDetails) object;
+                    results.put("remoteAddress", authenticationDetails.getRemoteAddress());
+                    results.put("sessionId", authenticationDetails.getSessionId());
+                } else if (object != null) {
+                    results.put(entry.getKey(), object.toString());
+                } else {
+                    results.put(entry.getKey(), "null");
+                }
+            }
+        }
+
+        return results;
+    }
+}

jhipster/src/main/java/com/baeldung/config/audit/package-info.java

@@ -0,0 +1,4 @@
+/**
+ * Audit specific code.
+ */
+package com.baeldung.config.audit;

jhipster/src/main/java/com/baeldung/config/package-info.java

@@ -0,0 +1,4 @@
+/**
+ * Spring Framework configuration files.
+ */
+package com.baeldung.config;

jhipster/src/main/java/com/baeldung/domain/AbstractAuditingEntity.java

@@ -0,0 +1,80 @@
+package com.baeldung.domain;
+
+import java.io.Serializable;
+
+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.time.ZonedDateTime;
+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", nullable = false)
+    @JsonIgnore
+    private ZonedDateTime createdDate = ZonedDateTime.now();
+
+    @LastModifiedBy
+    @Column(name = "last_modified_by", length = 50)
+    @JsonIgnore
+    private String lastModifiedBy;
+
+    @LastModifiedDate
+    @Column(name = "last_modified_date")
+    @JsonIgnore
+    private ZonedDateTime lastModifiedDate = ZonedDateTime.now();
+
+    public String getCreatedBy() {
+        return createdBy;
+    }
+
+    public void setCreatedBy(String createdBy) {
+        this.createdBy = createdBy;
+    }
+
+    public ZonedDateTime getCreatedDate() {
+        return createdDate;
+    }
+
+    public void setCreatedDate(ZonedDateTime createdDate) {
+        this.createdDate = createdDate;
+    }
+
+    public String getLastModifiedBy() {
+        return lastModifiedBy;
+    }
+
+    public void setLastModifiedBy(String lastModifiedBy) {
+        this.lastModifiedBy = lastModifiedBy;
+    }
+
+    public ZonedDateTime getLastModifiedDate() {
+        return lastModifiedDate;
+    }
+
+    public void setLastModifiedDate(ZonedDateTime lastModifiedDate) {
+        this.lastModifiedDate = lastModifiedDate;
+    }
+}

jhipster/src/main/java/com/baeldung/domain/Authority.java

@@ -0,0 +1,66 @@
+package com.baeldung.domain;
+
+import org.hibernate.annotations.Cache;
+import org.hibernate.annotations.CacheConcurrencyStrategy;
+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")
+@Cache(usage = CacheConcurrencyStrategy.NONSTRICT_READ_WRITE)
+public class Authority implements Serializable {
+
+    private static final long serialVersionUID = 1L;
+
+    @NotNull
+    @Size(min = 0, 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;
+
+        if (name != null ? !name.equals(authority.name) : authority.name != null) {
+            return false;
+        }
+
+        return true;
+    }
+
+    @Override
+    public int hashCode() {
+        return name != null ? name.hashCode() : 0;
+    }
+
+    @Override
+    public String toString() {
+        return "Authority{" +
+            "name='" + name + '\'' +
+            "}";
+    }
+}

jhipster/src/main/java/com/baeldung/domain/Comment.java

@@ -0,0 +1,114 @@
+package com.baeldung.domain;
+
+import org.hibernate.annotations.Cache;
+import org.hibernate.annotations.CacheConcurrencyStrategy;
+
+import javax.persistence.*;
+import javax.validation.constraints.*;
+import java.io.Serializable;
+import java.time.LocalDate;
+import java.util.Objects;
+
+/**
+ * A Comment.
+ */
+@Entity
+@Table(name = "comment")
+@Cache(usage = CacheConcurrencyStrategy.NONSTRICT_READ_WRITE)
+public class Comment implements Serializable {
+
+    private static final long serialVersionUID = 1L;
+
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    private Long id;
+
+    @NotNull
+    @Size(min = 10, max = 100)
+    @Column(name = "text", length = 100, nullable = false)
+    private String text;
+
+    @NotNull
+    @Column(name = "creation_date", nullable = false)
+    private LocalDate creationDate;
+
+    @ManyToOne(optional = false)
+    @NotNull
+    private Post post;
+
+    public Long getId() {
+        return id;
+    }
+
+    public void setId(Long id) {
+        this.id = id;
+    }
+
+    public String getText() {
+        return text;
+    }
+
+    public Comment text(String text) {
+        this.text = text;
+        return this;
+    }
+
+    public void setText(String text) {
+        this.text = text;
+    }
+
+    public LocalDate getCreationDate() {
+        return creationDate;
+    }
+
+    public Comment creationDate(LocalDate creationDate) {
+        this.creationDate = creationDate;
+        return this;
+    }
+
+    public void setCreationDate(LocalDate creationDate) {
+        this.creationDate = creationDate;
+    }
+
+    public Post getPost() {
+        return post;
+    }
+
+    public Comment post(Post post) {
+        this.post = post;
+        return this;
+    }
+
+    public void setPost(Post post) {
+        this.post = post;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) {
+            return true;
+        }
+        if (o == null || getClass() != o.getClass()) {
+            return false;
+        }
+        Comment comment = (Comment) o;
+        if (comment.id == null || id == null) {
+            return false;
+        }
+        return Objects.equals(id, comment.id);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hashCode(id);
+    }
+
+    @Override
+    public String toString() {
+        return "Comment{" +
+            "id=" + id +
+            ", text='" + text + "'" +
+            ", creationDate='" + creationDate + "'" +
+            '}';
+    }
+}

jhipster/src/main/java/com/baeldung/domain/PersistentAuditEvent.java

@@ -0,0 +1,78 @@
+package com.baeldung.domain;
+
+
+import java.io.Serializable;
+import java.time.LocalDateTime;
+import javax.persistence.*;
+import javax.validation.constraints.NotNull;
+import java.util.HashMap;
+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 {
+
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    @Column(name = "event_id")
+    private Long id;
+
+    @NotNull
+    @Column(nullable = false)
+    private String principal;
+
+    @Column(name = "event_date")
+    private LocalDateTime 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 LocalDateTime getAuditEventDate() {
+        return auditEventDate;
+    }
+
+    public void setAuditEventDate(LocalDateTime 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;
+    }
+}

jhipster/src/main/java/com/baeldung/domain/Post.java

@@ -0,0 +1,133 @@
+package com.baeldung.domain;
+
+import org.hibernate.annotations.Cache;
+import org.hibernate.annotations.CacheConcurrencyStrategy;
+
+import javax.persistence.*;
+import javax.validation.constraints.*;
+import java.io.Serializable;
+import java.time.LocalDate;
+import java.util.Objects;
+
+/**
+ * A Post.
+ */
+@Entity
+@Table(name = "post")
+@Cache(usage = CacheConcurrencyStrategy.NONSTRICT_READ_WRITE)
+public class Post implements Serializable {
+
+    private static final long serialVersionUID = 1L;
+
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    private Long id;
+
+    @NotNull
+    @Size(min = 10, max = 100)
+    @Column(name = "title", length = 100, nullable = false)
+    private String title;
+
+    @NotNull
+    @Size(min = 10, max = 1000)
+    @Column(name = "content", length = 1000, nullable = false)
+    private String content;
+
+    @NotNull
+    @Column(name = "creation_date", nullable = false)
+    private LocalDate creationDate;
+
+    @ManyToOne(optional = false)
+    @NotNull
+    private User creator;
+
+    public Long getId() {
+        return id;
+    }
+
+    public void setId(Long id) {
+        this.id = id;
+    }
+
+    public String getTitle() {
+        return title;
+    }
+
+    public Post title(String title) {
+        this.title = title;
+        return this;
+    }
+
+    public void setTitle(String title) {
+        this.title = title;
+    }
+
+    public String getContent() {
+        return content;
+    }
+
+    public Post content(String content) {
+        this.content = content;
+        return this;
+    }
+
+    public void setContent(String content) {
+        this.content = content;
+    }
+
+    public LocalDate getCreationDate() {
+        return creationDate;
+    }
+
+    public Post creationDate(LocalDate creationDate) {
+        this.creationDate = creationDate;
+        return this;
+    }
+
+    public void setCreationDate(LocalDate creationDate) {
+        this.creationDate = creationDate;
+    }
+
+    public User getCreator() {
+        return creator;
+    }
+
+    public Post creator(User user) {
+        this.creator = user;
+        return this;
+    }
+
+    public void setCreator(User user) {
+        this.creator = user;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) {
+            return true;
+        }
+        if (o == null || getClass() != o.getClass()) {
+            return false;
+        }
+        Post post = (Post) o;
+        if (post.id == null || id == null) {
+            return false;
+        }
+        return Objects.equals(id, post.id);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hashCode(id);
+    }
+
+    @Override
+    public String toString() {
+        return "Post{" +
+            "id=" + id +
+            ", title='" + title + "'" +
+            ", content='" + content + "'" +
+            ", creationDate='" + creationDate + "'" +
+            '}';
+    }
+}

jhipster/src/main/java/com/baeldung/domain/User.java

@@ -0,0 +1,235 @@
+package com.baeldung.domain;
+
+import com.baeldung.config.Constants;
+
+import com.fasterxml.jackson.annotation.JsonIgnore;
+import org.hibernate.annotations.BatchSize;
+import org.hibernate.annotations.Cache;
+import org.hibernate.annotations.CacheConcurrencyStrategy;
+import org.hibernate.validator.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.Set;
+import java.time.ZonedDateTime;
+
+/**
+ * A user.
+ */
+@Entity
+@Table(name = "jhi_user")
+@Cache(usage = CacheConcurrencyStrategy.NONSTRICT_READ_WRITE)
+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)
+    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(max = 100)
+    @Column(length = 100, unique = true)
+    private String email;
+
+    @NotNull
+    @Column(nullable = false)
+    private boolean activated = false;
+
+    @Size(min = 2, max = 5)
+    @Column(name = "lang_key", length = 5)
+    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)
+    private String resetKey;
+
+    @Column(name = "reset_date")
+    private ZonedDateTime resetDate = null;
+
+    @JsonIgnore
+    @ManyToMany
+    @JoinTable(
+        name = "jhi_user_authority",
+        joinColumns = {@JoinColumn(name = "user_id", referencedColumnName = "id")},
+        inverseJoinColumns = {@JoinColumn(name = "authority_name", referencedColumnName = "name")})
+    @Cache(usage = CacheConcurrencyStrategy.NONSTRICT_READ_WRITE)
+    @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 = login.toLowerCase(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 ZonedDateTime getResetDate() {
+       return resetDate;
+    }
+
+    public void setResetDate(ZonedDateTime 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;
+
+        if (!login.equals(user.login)) {
+            return false;
+        }
+
+        return true;
+    }
+
+    @Override
+    public int hashCode() {
+        return login.hashCode();
+    }
+
+    @Override
+    public String toString() {
+        return "User{" +
+            "login='" + login + '\'' +
+            ", firstName='" + firstName + '\'' +
+            ", lastName='" + lastName + '\'' +
+            ", email='" + email + '\'' +
+            ", imageUrl='" + imageUrl + '\'' +
+            ", activated='" + activated + '\'' +
+            ", langKey='" + langKey + '\'' +
+            ", activationKey='" + activationKey + '\'' +
+            "}";
+    }
+}

jhipster/src/main/java/com/baeldung/domain/package-info.java

@@ -0,0 +1,4 @@
+/**
+ * JPA domain objects.
+ */
+package com.baeldung.domain;

jhipster/src/main/java/com/baeldung/repository/AuthorityRepository.java

@@ -0,0 +1,11 @@
+package com.baeldung.repository;
+
+import com.baeldung.domain.Authority;
+
+import org.springframework.data.jpa.repository.JpaRepository;
+
+/**
+ * Spring Data JPA repository for the Authority entity.
+ */
+public interface AuthorityRepository extends JpaRepository<Authority, String> {
+}

jhipster/src/main/java/com/baeldung/repository/CommentRepository.java

@@ -0,0 +1,15 @@
+package com.baeldung.repository;
+
+import com.baeldung.domain.Comment;
+
+import org.springframework.data.jpa.repository.*;
+
+import java.util.List;
+
+/**
+ * Spring Data JPA repository for the Comment entity.
+ */
+@SuppressWarnings("unused")
+public interface CommentRepository extends JpaRepository<Comment,Long> {
+
+}

jhipster/src/main/java/com/baeldung/repository/CustomAuditEventRepository.java

@@ -0,0 +1,81 @@
+package com.baeldung.repository;
+
+import com.baeldung.config.Constants;
+import com.baeldung.config.audit.AuditEventConverter;
+import com.baeldung.domain.PersistentAuditEvent;
+
+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.time.LocalDateTime;
+import java.time.ZoneId;
+import java.util.Date;
+import java.util.List;
+
+/**
+ * An implementation of Spring Boot's AuditEventRepository.
+ */
+@Repository
+public class CustomAuditEventRepository implements AuditEventRepository {
+
+    private static final String AUTHORIZATION_FAILURE = "AUTHORIZATION_FAILURE";
+
+    private final PersistenceAuditEventRepository persistenceAuditEventRepository;
+
+    private final AuditEventConverter auditEventConverter;
+
+    public CustomAuditEventRepository(PersistenceAuditEventRepository persistenceAuditEventRepository,
+            AuditEventConverter auditEventConverter) {
+
+        this.persistenceAuditEventRepository = persistenceAuditEventRepository;
+        this.auditEventConverter = auditEventConverter;
+    }
+
+    @Override
+    public List<AuditEvent> find(Date after) {
+        Iterable<PersistentAuditEvent> persistentAuditEvents =
+            persistenceAuditEventRepository.findByAuditEventDateAfter(LocalDateTime.from(after.toInstant()));
+        return auditEventConverter.convertToAuditEvent(persistentAuditEvents);
+    }
+
+    @Override
+    public List<AuditEvent> find(String principal, Date after) {
+        Iterable<PersistentAuditEvent> persistentAuditEvents;
+        if (principal == null && after == null) {
+            persistentAuditEvents = persistenceAuditEventRepository.findAll();
+        } else if (after == null) {
+            persistentAuditEvents = persistenceAuditEventRepository.findByPrincipal(principal);
+        } else {
+            persistentAuditEvents =
+                persistenceAuditEventRepository.findByPrincipalAndAuditEventDateAfter(principal, LocalDateTime.from(after.toInstant()));
+        }
+        return auditEventConverter.convertToAuditEvent(persistentAuditEvents);
+    }
+
+    @Override
+    public List<AuditEvent> find(String principal, Date after, String type) {
+        Iterable<PersistentAuditEvent> persistentAuditEvents =
+            persistenceAuditEventRepository.findByPrincipalAndAuditEventDateAfterAndAuditEventType(principal, LocalDateTime.from(after.toInstant()), 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());
+            Instant instant = Instant.ofEpochMilli(event.getTimestamp().getTime());
+            persistentAuditEvent.setAuditEventDate(LocalDateTime.ofInstant(instant, ZoneId.systemDefault()));
+            persistentAuditEvent.setData(auditEventConverter.convertDataToStrings(event.getData()));
+            persistenceAuditEventRepository.save(persistentAuditEvent);
+        }
+    }
+}

jhipster/src/main/java/com/baeldung/repository/PersistenceAuditEventRepository.java

@@ -0,0 +1,26 @@
+package com.baeldung.repository;
+
+import com.baeldung.domain.PersistentAuditEvent;
+
+import java.time.LocalDateTime;
+import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.data.domain.Page;
+import org.springframework.data.domain.Pageable;
+
+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(LocalDateTime after);
+
+    List<PersistentAuditEvent> findByPrincipalAndAuditEventDateAfter(String principal, LocalDateTime after);
+
+    List<PersistentAuditEvent> findByPrincipalAndAuditEventDateAfterAndAuditEventType(String principle, LocalDateTime after, String type);
+
+    Page<PersistentAuditEvent> findAllByAuditEventDateBetween(LocalDateTime fromDate, LocalDateTime toDate, Pageable pageable);
+}

jhipster/src/main/java/com/baeldung/repository/PostRepository.java

@@ -0,0 +1,18 @@
+package com.baeldung.repository;
+
+import com.baeldung.domain.Post;
+
+import org.springframework.data.jpa.repository.*;
+
+import java.util.List;
+
+/**
+ * Spring Data JPA repository for the Post entity.
+ */
+@SuppressWarnings("unused")
+public interface PostRepository extends JpaRepository<Post,Long> {
+
+    @Query("select post from Post post where post.creator.login = ?#{principal.username}")
+    List<Post> findByCreatorIsCurrentUser();
+
+}

jhipster/src/main/java/com/baeldung/repository/UserRepository.java

@@ -0,0 +1,37 @@
+package com.baeldung.repository;
+
+import com.baeldung.domain.User;
+
+import java.time.ZonedDateTime;
+
+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 java.util.List;
+import java.util.Optional;
+
+/**
+ * Spring Data JPA repository for the User entity.
+ */
+public interface UserRepository extends JpaRepository<User, Long> {
+
+    Optional<User> findOneByActivationKey(String activationKey);
+
+    List<User> findAllByActivatedIsFalseAndCreatedDateBefore(ZonedDateTime dateTime);
+
+    Optional<User> findOneByResetKey(String resetKey);
+
+    Optional<User> findOneByEmail(String email);
+
+    Optional<User> findOneByLogin(String login);
+
+    @EntityGraph(attributePaths = "authorities")
+    User findOneWithAuthoritiesById(Long id);
+
+    @EntityGraph(attributePaths = "authorities")
+    Optional<User> findOneWithAuthoritiesByLogin(String login);
+
+    Page<User> findAllByLoginNot(Pageable pageable, String login);
+}

jhipster/src/main/java/com/baeldung/repository/package-info.java

@@ -0,0 +1,4 @@
+/**
+ * Spring Data JPA repositories.
+ */
+package com.baeldung.repository;

jhipster/src/main/java/com/baeldung/security/AuthoritiesConstants.java

@@ -0,0 +1,16 @@
+package com.baeldung.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() {
+    }
+}

jhipster/src/main/java/com/baeldung/security/DomainUserDetailsService.java

@@ -0,0 +1,51 @@
+package com.baeldung.security;
+
+import com.baeldung.domain.User;
+import com.baeldung.repository.UserRepository;
+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);
+        String lowercaseLogin = login.toLowerCase(Locale.ENGLISH);
+        Optional<User> userFromDatabase = userRepository.findOneWithAuthoritiesByLogin(lowercaseLogin);
+        return userFromDatabase.map(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(lowercaseLogin,
+                user.getPassword(),
+                grantedAuthorities);
+        }).orElseThrow(() -> new UsernameNotFoundException("User " + lowercaseLogin + " was not found in the " +
+        "database"));
+    }
+}

jhipster/src/main/java/com/baeldung/security/SecurityUtils.java

@@ -0,0 +1,68 @@
+package com.baeldung.security;
+
+import org.springframework.security.core.Authentication;
+import org.springframework.security.core.context.SecurityContext;
+import org.springframework.security.core.context.SecurityContextHolder;
+import org.springframework.security.core.userdetails.UserDetails;
+
+/**
+ * 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 String getCurrentUserLogin() {
+        SecurityContext securityContext = SecurityContextHolder.getContext();
+        Authentication authentication = securityContext.getAuthentication();
+        String userName = null;
+        if (authentication != null) {
+            if (authentication.getPrincipal() instanceof UserDetails) {
+                UserDetails springSecurityUser = (UserDetails) authentication.getPrincipal();
+                userName = springSecurityUser.getUsername();
+            } else if (authentication.getPrincipal() instanceof String) {
+                userName = (String) authentication.getPrincipal();
+            }
+        }
+        return userName;
+    }
+
+    /**
+     * Check if a user is authenticated.
+     *
+     * @return true if the user is authenticated, false otherwise
+     */
+    public static boolean isAuthenticated() {
+        SecurityContext securityContext = SecurityContextHolder.getContext();
+        Authentication authentication = securityContext.getAuthentication();
+        if (authentication != null) {
+            return authentication.getAuthorities().stream()
+                .noneMatch(grantedAuthority -> grantedAuthority.getAuthority().equals(AuthoritiesConstants.ANONYMOUS));
+        }
+        return 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</p>
+     *
+     * @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();
+        Authentication authentication = securityContext.getAuthentication();
+        if (authentication != null) {
+            return authentication.getAuthorities().stream()
+                .anyMatch(grantedAuthority -> grantedAuthority.getAuthority().equals(authority));
+        }
+        return false;
+    }
+}

jhipster/src/main/java/com/baeldung/security/SpringSecurityAuditorAware.java

@@ -0,0 +1,19 @@
+package com.baeldung.security;
+
+import com.baeldung.config.Constants;
+
+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 String getCurrentAuditor() {
+        String userName = SecurityUtils.getCurrentUserLogin();
+        return userName != null ? userName : Constants.SYSTEM_ACCOUNT;
+    }
+}

jhipster/src/main/java/com/baeldung/security/UserNotActivatedException.java

@@ -0,0 +1,19 @@
+package com.baeldung.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);
+    }
+}

jhipster/src/main/java/com/baeldung/security/jwt/JWTConfigurer.java

@@ -0,0 +1,23 @@
+package com.baeldung.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> {
+
+    public static final String AUTHORIZATION_HEADER = "Authorization";
+
+    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);
+    }
+}

jhipster/src/main/java/com/baeldung/security/jwt/JWTFilter.java

@@ -0,0 +1,58 @@
+package com.baeldung.security.jwt;
+
+import java.io.IOException;
+import javax.servlet.*;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+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 io.jsonwebtoken.ExpiredJwtException;
+
+/**
+ * Filters incoming requests and installs a Spring Security principal if a header corresponding to a valid user is
+ * found.
+ */
+public class JWTFilter extends GenericFilterBean {
+
+    private final Logger log = LoggerFactory.getLogger(JWTFilter.class);
+
+    private TokenProvider tokenProvider;
+
+    public JWTFilter(TokenProvider tokenProvider) {
+        this.tokenProvider = tokenProvider;
+    }
+
+    @Override
+    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain)
+        throws IOException, ServletException {
+        try {
+            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);
+        } catch (ExpiredJwtException eje) {
+            log.info("Security exception for user {} - {}",
+                eje.getClaims().getSubject(), eje.getMessage());
+
+            log.trace("Security exception trace: {}", eje);
+            ((HttpServletResponse) servletResponse).setStatus(HttpServletResponse.SC_UNAUTHORIZED);
+        }
+    }
+
+    private String resolveToken(HttpServletRequest request){
+        String bearerToken = request.getHeader(JWTConfigurer.AUTHORIZATION_HEADER);
+        if (StringUtils.hasText(bearerToken) && bearerToken.startsWith("Bearer ")) {
+            return bearerToken.substring(7, bearerToken.length());
+        }
+        return null;
+    }
+}

jhipster/src/main/java/com/baeldung/security/jwt/TokenProvider.java

@@ -0,0 +1,109 @@
+package com.baeldung.security.jwt;
+
+import io.github.jhipster.config.JHipsterProperties;
+
+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 io.jsonwebtoken.*;
+
+@Component
+public class TokenProvider {
+
+    private final Logger log = LoggerFactory.getLogger(TokenProvider.class);
+
+    private static final String AUTHORITIES_KEY = "auth";
+
+    private String secretKey;
+
+    private long tokenValidityInMilliseconds;
+
+    private long tokenValidityInMillisecondsForRememberMe;
+
+    private final JHipsterProperties jHipsterProperties;
+
+    public TokenProvider(JHipsterProperties jHipsterProperties) {
+        this.jHipsterProperties = jHipsterProperties;
+    }
+
+    @PostConstruct
+    public void init() {
+        this.secretKey =
+            jHipsterProperties.getSecurity().getAuthentication().getJwt().getSecret();
+
+        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(SignatureAlgorithm.HS512, secretKey)
+            .setExpiration(validity)
+            .compact();
+    }
+
+    public Authentication getAuthentication(String token) {
+        Claims claims = Jwts.parser()
+            .setSigningKey(secretKey)
+            .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, "", authorities);
+    }
+
+    public boolean validateToken(String authToken) {
+        try {
+            Jwts.parser().setSigningKey(secretKey).parseClaimsJws(authToken);
+            return true;
+        } catch (SignatureException e) {
+            log.info("Invalid JWT signature.");
+            log.trace("Invalid JWT signature trace: {}", e);
+        } catch (MalformedJwtException e) {
+            log.info("Invalid JWT token.");
+            log.trace("Invalid JWT token 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;
+    }
+}

jhipster/src/main/java/com/baeldung/security/package-info.java

@@ -0,0 +1,4 @@
+/**
+ * Spring Security configuration.
+ */
+package com.baeldung.security;

jhipster/src/main/java/com/baeldung/service/AuditEventService.java

@@ -0,0 +1,50 @@
+package com.baeldung.service;
+
+import com.baeldung.config.audit.AuditEventConverter;
+import com.baeldung.repository.PersistenceAuditEventRepository;
+import java.time.LocalDateTime;
+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.util.Optional;
+
+/**
+ * Service for managing audit events.
+ * <p>
+ * This is the default implementation to support SpringBoot Actuator AuditEventRepository
+ * </p>
+ */
+@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(LocalDateTime fromDate, LocalDateTime toDate, Pageable pageable) {
+        return persistenceAuditEventRepository.findAllByAuditEventDateBetween(fromDate, toDate, pageable)
+            .map(auditEventConverter::convertToAuditEvent);
+    }
+
+    public Optional<AuditEvent> find(Long id) {
+        return Optional.ofNullable(persistenceAuditEventRepository.findOne(id)).map
+            (auditEventConverter::convertToAuditEvent);
+    }
+}

jhipster/src/main/java/com/baeldung/service/MailService.java

@@ -0,0 +1,108 @@
+package com.baeldung.service;
+
+import com.baeldung.domain.User;
+
+import io.github.jhipster.config.JHipsterProperties;
+
+import org.apache.commons.lang3.CharEncoding;
+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.spring4.SpringTemplateEngine;
+
+import javax.mail.internet.MimeMessage;
+import java.util.Locale;
+
+/**
+ * Service for sending e-mails.
+ * <p>
+ * We use the @Async annotation to send e-mails asynchronously.
+ * </p>
+ */
+@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 e-mail[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, CharEncoding.UTF_8);
+            message.setTo(to);
+            message.setFrom(jHipsterProperties.getMail().getFrom());
+            message.setSubject(subject);
+            message.setText(content, isHtml);
+            javaMailSender.send(mimeMessage);
+            log.debug("Sent e-mail to User '{}'", to);
+        } catch (Exception e) {
+            log.warn("E-mail could not be sent to user '{}'", to, e);
+        }
+    }
+
+    @Async
+    public void sendActivationEmail(User user) {
+        log.debug("Sending activation e-mail to '{}'", user.getEmail());
+        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("activationEmail", context);
+        String subject = messageSource.getMessage("email.activation.title", null, locale);
+        sendEmail(user.getEmail(), subject, content, false, true);
+    }
+
+    @Async
+    public void sendCreationEmail(User user) {
+        log.debug("Sending creation e-mail to '{}'", user.getEmail());
+        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("creationEmail", context);
+        String subject = messageSource.getMessage("email.activation.title", null, locale);
+        sendEmail(user.getEmail(), subject, content, false, true);
+    }
+
+    @Async
+    public void sendPasswordResetMail(User user) {
+        log.debug("Sending password reset e-mail to '{}'", user.getEmail());
+        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("passwordResetEmail", context);
+        String subject = messageSource.getMessage("email.reset.title", null, locale);
+        sendEmail(user.getEmail(), subject, content, false, true);
+    }
+}

jhipster/src/main/java/com/baeldung/service/UserService.java

@@ -0,0 +1,228 @@
+package com.baeldung.service;
+
+import com.baeldung.domain.Authority;
+import com.baeldung.domain.User;
+import com.baeldung.repository.AuthorityRepository;
+import com.baeldung.config.Constants;
+import com.baeldung.repository.UserRepository;
+import com.baeldung.security.AuthoritiesConstants;
+import com.baeldung.security.SecurityUtils;
+import com.baeldung.service.util.RandomUtil;
+import com.baeldung.service.dto.UserDTO;
+
+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.ZonedDateTime;
+import java.util.*;
+
+/**
+ * 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 -> {
+                ZonedDateTime oneDayAgo = ZonedDateTime.now().minusHours(24);
+                return user.getResetDate().isAfter(oneDayAgo);
+           })
+           .map(user -> {
+                user.setPassword(passwordEncoder.encode(newPassword));
+                user.setResetKey(null);
+                user.setResetDate(null);
+                return user;
+           });
+    }
+
+    public Optional<User> requestPasswordReset(String mail) {
+        return userRepository.findOneByEmail(mail)
+            .filter(User::getActivated)
+            .map(user -> {
+                user.setResetKey(RandomUtil.generateResetKey());
+                user.setResetDate(ZonedDateTime.now());
+                return user;
+            });
+    }
+
+    public User createUser(String login, String password, String firstName, String lastName, String email,
+        String imageUrl, String langKey) {
+
+        User newUser = new User();
+        Authority authority = authorityRepository.findOne(AuthoritiesConstants.USER);
+        Set<Authority> authorities = new HashSet<>();
+        String encryptedPassword = passwordEncoder.encode(password);
+        newUser.setLogin(login);
+        // new user gets initially a generated password
+        newUser.setPassword(encryptedPassword);
+        newUser.setFirstName(firstName);
+        newUser.setLastName(lastName);
+        newUser.setEmail(email);
+        newUser.setImageUrl(imageUrl);
+        newUser.setLangKey(langKey);
+        // new user is not active
+        newUser.setActivated(false);
+        // new user gets registration key
+        newUser.setActivationKey(RandomUtil.generateActivationKey());
+        authorities.add(authority);
+        newUser.setAuthorities(authorities);
+        userRepository.save(newUser);
+        log.debug("Created Information for User: {}", newUser);
+        return newUser;
+    }
+
+    public User createUser(UserDTO userDTO) {
+        User user = new User();
+        user.setLogin(userDTO.getLogin());
+        user.setFirstName(userDTO.getFirstName());
+        user.setLastName(userDTO.getLastName());
+        user.setEmail(userDTO.getEmail());
+        user.setImageUrl(userDTO.getImageUrl());
+        if (userDTO.getLangKey() == null) {
+            user.setLangKey("en"); // default language
+        } else {
+            user.setLangKey(userDTO.getLangKey());
+        }
+        if (userDTO.getAuthorities() != null) {
+            Set<Authority> authorities = new HashSet<>();
+            userDTO.getAuthorities().forEach(
+                authority -> authorities.add(authorityRepository.findOne(authority))
+            );
+            user.setAuthorities(authorities);
+        }
+        String encryptedPassword = passwordEncoder.encode(RandomUtil.generatePassword());
+        user.setPassword(encryptedPassword);
+        user.setResetKey(RandomUtil.generateResetKey());
+        user.setResetDate(ZonedDateTime.now());
+        user.setActivated(true);
+        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.
+     */
+    public void updateUser(String firstName, String lastName, String email, String langKey) {
+        userRepository.findOneByLogin(SecurityUtils.getCurrentUserLogin()).ifPresent(user -> {
+            user.setFirstName(firstName);
+            user.setLastName(lastName);
+            user.setEmail(email);
+            user.setLangKey(langKey);
+            log.debug("Changed Information for User: {}", user);
+        });
+    }
+
+    /**
+     * Update all information for a specific user, and return the modified user.
+     */
+    public Optional<UserDTO> updateUser(UserDTO userDTO) {
+        return Optional.of(userRepository
+            .findOne(userDTO.getId()))
+            .map(user -> {
+                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> managedAuthorities = user.getAuthorities();
+                managedAuthorities.clear();
+                userDTO.getAuthorities().stream()
+                    .map(authorityRepository::findOne)
+                    .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 password) {
+        userRepository.findOneByLogin(SecurityUtils.getCurrentUserLogin()).ifPresent(user -> {
+            String encryptedPassword = passwordEncoder.encode(password);
+            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 User getUserWithAuthorities(Long id) {
+        return userRepository.findOneWithAuthoritiesById(id);
+    }
+
+    @Transactional(readOnly = true)
+    public User getUserWithAuthorities() {
+        return userRepository.findOneWithAuthoritiesByLogin(SecurityUtils.getCurrentUserLogin()).orElse(null);
+    }
+
+
+    /**
+     * Not activated users should be automatically deleted after 3 days.
+     * <p>
+     * This is scheduled to get fired everyday, at 01:00 (am).
+     * </p>
+     */
+    @Scheduled(cron = "0 0 1 * * ?")
+    public void removeNotActivatedUsers() {
+        ZonedDateTime now = ZonedDateTime.now();
+        List<User> users = userRepository.findAllByActivatedIsFalseAndCreatedDateBefore(now.minusDays(3));
+        for (User user : users) {
+            log.debug("Deleting not activated user {}", user.getLogin());
+            userRepository.delete(user);
+        }
+    }
+}

jhipster/src/main/java/com/baeldung/service/dto/UserDTO.java

@@ -0,0 +1,167 @@
+package com.baeldung.service.dto;
+
+import com.baeldung.config.Constants;
+
+import com.baeldung.domain.Authority;
+import com.baeldung.domain.User;
+
+import org.hibernate.validator.constraints.Email;
+
+import javax.validation.constraints.*;
+import java.time.ZonedDateTime;
+import java.util.Set;
+import java.util.stream.Collectors;
+
+/**
+ * A DTO representing a user, with his authorities.
+ */
+public class UserDTO {
+
+    private Long id;
+
+    @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 = 100)
+    private String email;
+
+    @Size(max = 256)
+    private String imageUrl;
+
+    private boolean activated = false;
+
+    @Size(min = 2, max = 5)
+    private String langKey;
+
+    private String createdBy;
+
+    private ZonedDateTime createdDate;
+
+    private String lastModifiedBy;
+
+    private ZonedDateTime lastModifiedDate;
+
+    private Set<String> authorities;
+
+    public UserDTO() {
+        // Empty constructor needed for MapStruct.
+    }
+
+    public UserDTO(User user) {
+        this(user.getId(), user.getLogin(), user.getFirstName(), user.getLastName(),
+            user.getEmail(), user.getActivated(), user.getImageUrl(), user.getLangKey(),
+            user.getCreatedBy(), user.getCreatedDate(), user.getLastModifiedBy(), user.getLastModifiedDate(),
+            user.getAuthorities().stream().map(Authority::getName)
+                .collect(Collectors.toSet()));
+    }
+
+    public UserDTO(Long id, String login, String firstName, String lastName,
+        String email, boolean activated, String imageUrl, String langKey,
+        String createdBy, ZonedDateTime createdDate, String lastModifiedBy, ZonedDateTime lastModifiedDate,
+        Set<String> authorities) {
+
+        this.id = id;
+        this.login = login;
+        this.firstName = firstName;
+        this.lastName = lastName;
+        this.email = email;
+        this.activated = activated;
+        this.imageUrl = imageUrl;
+        this.langKey = langKey;
+        this.createdBy = createdBy;
+        this.createdDate = createdDate;
+        this.lastModifiedBy = lastModifiedBy;
+        this.lastModifiedDate = lastModifiedDate;
+        this.authorities = authorities;
+    }
+
+    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 String getLastName() {
+        return lastName;
+    }
+
+    public String getEmail() {
+        return email;
+    }
+
+    public String getImageUrl() {
+        return imageUrl;
+    }
+
+    public boolean isActivated() {
+        return activated;
+    }
+
+    public String getLangKey() {
+        return langKey;
+    }
+
+    public String getCreatedBy() {
+        return createdBy;
+    }
+
+    public ZonedDateTime getCreatedDate() {
+        return createdDate;
+    }
+
+    public String getLastModifiedBy() {
+        return lastModifiedBy;
+    }
+
+    public ZonedDateTime getLastModifiedDate() {
+        return lastModifiedDate;
+    }
+
+    public void setLastModifiedDate(ZonedDateTime lastModifiedDate) {
+        this.lastModifiedDate = lastModifiedDate;
+    }
+
+    public Set<String> getAuthorities() {
+        return 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 +
+            "}";
+    }
+}

jhipster/src/main/java/com/baeldung/service/dto/package-info.java

@@ -0,0 +1,4 @@
+/**
+ * Data Transfer Objects.
+ */
+package com.baeldung.service.dto;

jhipster/src/main/java/com/baeldung/service/mapper/UserMapper.java

@@ -0,0 +1,55 @@
+package com.baeldung.service.mapper;
+
+import com.baeldung.domain.Authority;
+import com.baeldung.domain.User;
+import com.baeldung.service.dto.UserDTO;
+import org.mapstruct.*;
+
+import java.util.List;
+import java.util.Set;
+import java.util.stream.Collectors;
+
+/**
+ * Mapper for the entity User and its DTO UserDTO.
+ */
+@Mapper(componentModel = "spring", uses = {})
+public interface UserMapper {
+
+    UserDTO userToUserDTO(User user);
+
+    List<UserDTO> usersToUserDTOs(List<User> users);
+
+    @Mapping(target = "createdBy", ignore = true)
+    @Mapping(target = "createdDate", ignore = true)
+    @Mapping(target = "lastModifiedBy", ignore = true)
+    @Mapping(target = "lastModifiedDate", ignore = true)
+    @Mapping(target = "activationKey", ignore = true)
+    @Mapping(target = "resetKey", ignore = true)
+    @Mapping(target = "resetDate", ignore = true)
+    @Mapping(target = "password", ignore = true)
+    User userDTOToUser(UserDTO userDTO);
+
+    List<User> userDTOsToUsers(List<UserDTO> userDTOs);
+
+    default User userFromId(Long id) {
+        if (id == null) {
+            return null;
+        }
+        User user = new User();
+        user.setId(id);
+        return user;
+    }
+
+    default Set<String> stringsFromAuthorities (Set<Authority> authorities) {
+        return authorities.stream().map(Authority::getName)
+            .collect(Collectors.toSet());
+    }
+
+    default Set<Authority> authoritiesFromStrings(Set<String> strings) {
+        return strings.stream().map(string -> {
+            Authority auth = new Authority();
+            auth.setName(string);
+            return auth;
+        }).collect(Collectors.toSet());
+    }
+}

jhipster/src/main/java/com/baeldung/service/mapper/package-info.java

@@ -0,0 +1,4 @@
+/**
+ * MapStruct mappers for mapping domain objects and Data Transfer Objects.
+ */
+package com.baeldung.service.mapper;

jhipster/src/main/java/com/baeldung/service/package-info.java

@@ -0,0 +1,4 @@
+/**
+ * Service layer beans.
+ */
+package com.baeldung.service;

jhipster/src/main/java/com/baeldung/service/util/RandomUtil.java

@@ -0,0 +1,41 @@
+package com.baeldung.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);
+    }
+}

jhipster/src/main/java/com/baeldung/web/rest/AccountResource.java

@@ -0,0 +1,202 @@
+package com.baeldung.web.rest;
+
+import com.codahale.metrics.annotation.Timed;
+
+import com.baeldung.domain.User;
+import com.baeldung.repository.UserRepository;
+import com.baeldung.security.SecurityUtils;
+import com.baeldung.service.MailService;
+import com.baeldung.service.UserService;
+import com.baeldung.service.dto.UserDTO;
+import com.baeldung.web.rest.vm.KeyAndPasswordVM;
+import com.baeldung.web.rest.vm.ManagedUserVM;
+import com.baeldung.web.rest.util.HeaderUtil;
+
+import org.apache.commons.lang3.StringUtils;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.MediaType;
+import org.springframework.http.ResponseEntity;
+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
+     * @return the ResponseEntity with status 201 (Created) if the user is registered or 400 (Bad Request) if the login or e-mail is already in use
+     */
+    @PostMapping(path = "/register",
+                    produces={MediaType.APPLICATION_JSON_VALUE, MediaType.TEXT_PLAIN_VALUE})
+    @Timed
+    public ResponseEntity registerAccount(@Valid @RequestBody ManagedUserVM managedUserVM) {
+
+        HttpHeaders textPlainHeaders = new HttpHeaders();
+        textPlainHeaders.setContentType(MediaType.TEXT_PLAIN);
+
+        return userRepository.findOneByLogin(managedUserVM.getLogin().toLowerCase())
+            .map(user -> new ResponseEntity<>("login already in use", textPlainHeaders, HttpStatus.BAD_REQUEST))
+            .orElseGet(() -> userRepository.findOneByEmail(managedUserVM.getEmail())
+                .map(user -> new ResponseEntity<>("e-mail address already in use", textPlainHeaders, HttpStatus.BAD_REQUEST))
+                .orElseGet(() -> {
+                    User user = userService
+                        .createUser(managedUserVM.getLogin(), managedUserVM.getPassword(),
+                            managedUserVM.getFirstName(), managedUserVM.getLastName(),
+                            managedUserVM.getEmail().toLowerCase(), managedUserVM.getImageUrl(), managedUserVM.getLangKey());
+
+                    mailService.sendActivationEmail(user);
+                    return new ResponseEntity<>(HttpStatus.CREATED);
+                })
+        );
+    }
+
+    /**
+     * GET  /activate : activate the registered user.
+     *
+     * @param key the activation key
+     * @return the ResponseEntity with status 200 (OK) and the activated user in body, or status 500 (Internal Server Error) if the user couldn't be activated
+     */
+    @GetMapping("/activate")
+    @Timed
+    public ResponseEntity<String> activateAccount(@RequestParam(value = "key") String key) {
+        return userService.activateRegistration(key)
+            .map(user -> new ResponseEntity<String>(HttpStatus.OK))
+            .orElse(new ResponseEntity<>(HttpStatus.INTERNAL_SERVER_ERROR));
+    }
+
+    /**
+     * 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")
+    @Timed
+    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 ResponseEntity with status 200 (OK) and the current user in body, or status 500 (Internal Server Error) if the user couldn't be returned
+     */
+    @GetMapping("/account")
+    @Timed
+    public ResponseEntity<UserDTO> getAccount() {
+        return Optional.ofNullable(userService.getUserWithAuthorities())
+            .map(user -> new ResponseEntity<>(new UserDTO(user), HttpStatus.OK))
+            .orElse(new ResponseEntity<>(HttpStatus.INTERNAL_SERVER_ERROR));
+    }
+
+    /**
+     * POST  /account : update the current user information.
+     *
+     * @param userDTO the current user information
+     * @return the ResponseEntity with status 200 (OK), or status 400 (Bad Request) or 500 (Internal Server Error) if the user couldn't be updated
+     */
+    @PostMapping("/account")
+    @Timed
+    public ResponseEntity saveAccount(@Valid @RequestBody UserDTO userDTO) {
+        Optional<User> existingUser = userRepository.findOneByEmail(userDTO.getEmail());
+        if (existingUser.isPresent() && (!existingUser.get().getLogin().equalsIgnoreCase(userDTO.getLogin()))) {
+            return ResponseEntity.badRequest().headers(HeaderUtil.createFailureAlert("user-management", "emailexists", "Email already in use")).body(null);
+        }
+        return userRepository
+            .findOneByLogin(SecurityUtils.getCurrentUserLogin())
+            .map(u -> {
+                userService.updateUser(userDTO.getFirstName(), userDTO.getLastName(), userDTO.getEmail(),
+                    userDTO.getLangKey());
+                return new ResponseEntity(HttpStatus.OK);
+            })
+            .orElseGet(() -> new ResponseEntity<>(HttpStatus.INTERNAL_SERVER_ERROR));
+    }
+
+    /**
+     * POST  /account/change_password : changes the current user's password
+     *
+     * @param password the new password
+     * @return the ResponseEntity with status 200 (OK), or status 400 (Bad Request) if the new password is not strong enough
+     */
+    @PostMapping(path = "/account/change_password",
+        produces = MediaType.TEXT_PLAIN_VALUE)
+    @Timed
+    public ResponseEntity changePassword(@RequestBody String password) {
+        if (!checkPasswordLength(password)) {
+            return new ResponseEntity<>("Incorrect password", HttpStatus.BAD_REQUEST);
+        }
+        userService.changePassword(password);
+        return new ResponseEntity<>(HttpStatus.OK);
+    }
+
+    /**
+     * POST   /account/reset_password/init : Send an e-mail to reset the password of the user
+     *
+     * @param mail the mail of the user
+     * @return the ResponseEntity with status 200 (OK) if the e-mail was sent, or status 400 (Bad Request) if the e-mail address is not registered
+     */
+    @PostMapping(path = "/account/reset_password/init",
+        produces = MediaType.TEXT_PLAIN_VALUE)
+    @Timed
+    public ResponseEntity requestPasswordReset(@RequestBody String mail) {
+        return userService.requestPasswordReset(mail)
+            .map(user -> {
+                mailService.sendPasswordResetMail(user);
+                return new ResponseEntity<>("e-mail was sent", HttpStatus.OK);
+            }).orElse(new ResponseEntity<>("e-mail address not registered", HttpStatus.BAD_REQUEST));
+    }
+
+    /**
+     * POST   /account/reset_password/finish : Finish to reset the password of the user
+     *
+     * @param keyAndPassword the generated key and the new password
+     * @return the ResponseEntity with status 200 (OK) if the password has been reset,
+     * or status 400 (Bad Request) or 500 (Internal Server Error) if the password could not be reset
+     */
+    @PostMapping(path = "/account/reset_password/finish",
+        produces = MediaType.TEXT_PLAIN_VALUE)
+    @Timed
+    public ResponseEntity<String> finishPasswordReset(@RequestBody KeyAndPasswordVM keyAndPassword) {
+        if (!checkPasswordLength(keyAndPassword.getNewPassword())) {
+            return new ResponseEntity<>("Incorrect password", HttpStatus.BAD_REQUEST);
+        }
+        return userService.completePasswordReset(keyAndPassword.getNewPassword(), keyAndPassword.getKey())
+              .map(user -> new ResponseEntity<String>(HttpStatus.OK))
+              .orElse(new ResponseEntity<>(HttpStatus.INTERNAL_SERVER_ERROR));
+    }
+
+    private boolean checkPasswordLength(String password) {
+        return !StringUtils.isEmpty(password) &&
+            password.length() >= ManagedUserVM.PASSWORD_MIN_LENGTH &&
+            password.length() <= ManagedUserVM.PASSWORD_MAX_LENGTH;
+    }
+}

jhipster/src/main/java/com/baeldung/web/rest/AuditResource.java

@@ -0,0 +1,76 @@
+package com.baeldung.web.rest;
+
+import com.baeldung.service.AuditEventService;
+import com.baeldung.web.rest.util.PaginationUtil;
+
+import io.github.jhipster.web.util.ResponseUtil;
+import io.swagger.annotations.ApiParam;
+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.net.URISyntaxException;
+import java.time.LocalDate;
+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(@ApiParam 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,
+        @ApiParam Pageable pageable) {
+
+        Page<AuditEvent> page = auditEventService.findByDates(fromDate.atTime(0, 0), toDate.atTime(23, 59), 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));
+    }
+}

jhipster/src/main/java/com/baeldung/web/rest/CommentResource.java

@@ -0,0 +1,129 @@
+package com.baeldung.web.rest;
+
+import com.codahale.metrics.annotation.Timed;
+import com.baeldung.domain.Comment;
+
+import com.baeldung.repository.CommentRepository;
+import com.baeldung.web.rest.util.HeaderUtil;
+import com.baeldung.web.rest.util.PaginationUtil;
+import io.swagger.annotations.ApiParam;
+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.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 Comment.
+ */
+@RestController
+@RequestMapping("/api")
+public class CommentResource {
+
+    private final Logger log = LoggerFactory.getLogger(CommentResource.class);
+
+    private static final String ENTITY_NAME = "comment";
+        
+    private final CommentRepository commentRepository;
+
+    public CommentResource(CommentRepository commentRepository) {
+        this.commentRepository = commentRepository;
+    }
+
+    /**
+     * POST  /comments : Create a new comment.
+     *
+     * @param comment the comment to create
+     * @return the ResponseEntity with status 201 (Created) and with body the new comment, or with status 400 (Bad Request) if the comment has already an ID
+     * @throws URISyntaxException if the Location URI syntax is incorrect
+     */
+    @PostMapping("/comments")
+    @Timed
+    public ResponseEntity<Comment> createComment(@Valid @RequestBody Comment comment) throws URISyntaxException {
+        log.debug("REST request to save Comment : {}", comment);
+        if (comment.getId() != null) {
+            return ResponseEntity.badRequest().headers(HeaderUtil.createFailureAlert(ENTITY_NAME, "idexists", "A new comment cannot already have an ID")).body(null);
+        }
+        Comment result = commentRepository.save(comment);
+        return ResponseEntity.created(new URI("/api/comments/" + result.getId()))
+            .headers(HeaderUtil.createEntityCreationAlert(ENTITY_NAME, result.getId().toString()))
+            .body(result);
+    }
+
+    /**
+     * PUT  /comments : Updates an existing comment.
+     *
+     * @param comment the comment to update
+     * @return the ResponseEntity with status 200 (OK) and with body the updated comment,
+     * or with status 400 (Bad Request) if the comment is not valid,
+     * or with status 500 (Internal Server Error) if the comment couldnt be updated
+     * @throws URISyntaxException if the Location URI syntax is incorrect
+     */
+    @PutMapping("/comments")
+    @Timed
+    public ResponseEntity<Comment> updateComment(@Valid @RequestBody Comment comment) throws URISyntaxException {
+        log.debug("REST request to update Comment : {}", comment);
+        if (comment.getId() == null) {
+            return createComment(comment);
+        }
+        Comment result = commentRepository.save(comment);
+        return ResponseEntity.ok()
+            .headers(HeaderUtil.createEntityUpdateAlert(ENTITY_NAME, comment.getId().toString()))
+            .body(result);
+    }
+
+    /**
+     * GET  /comments : get all the comments.
+     *
+     * @param pageable the pagination information
+     * @return the ResponseEntity with status 200 (OK) and the list of comments in body
+     * @throws URISyntaxException if there is an error to generate the pagination HTTP headers
+     */
+    @GetMapping("/comments")
+    @Timed
+    public ResponseEntity<List<Comment>> getAllComments(@ApiParam Pageable pageable) {
+        log.debug("REST request to get a page of Comments");
+        Page<Comment> page = commentRepository.findAll(pageable);
+        HttpHeaders headers = PaginationUtil.generatePaginationHttpHeaders(page, "/api/comments");
+        return new ResponseEntity<>(page.getContent(), headers, HttpStatus.OK);
+    }
+
+    /**
+     * GET  /comments/:id : get the "id" comment.
+     *
+     * @param id the id of the comment to retrieve
+     * @return the ResponseEntity with status 200 (OK) and with body the comment, or with status 404 (Not Found)
+     */
+    @GetMapping("/comments/{id}")
+    @Timed
+    public ResponseEntity<Comment> getComment(@PathVariable Long id) {
+        log.debug("REST request to get Comment : {}", id);
+        Comment comment = commentRepository.findOne(id);
+        return ResponseUtil.wrapOrNotFound(Optional.ofNullable(comment));
+    }
+
+    /**
+     * DELETE  /comments/:id : delete the "id" comment.
+     *
+     * @param id the id of the comment to delete
+     * @return the ResponseEntity with status 200 (OK)
+     */
+    @DeleteMapping("/comments/{id}")
+    @Timed
+    public ResponseEntity<Void> deleteComment(@PathVariable Long id) {
+        log.debug("REST request to delete Comment : {}", id);
+        commentRepository.delete(id);
+        return ResponseEntity.ok().headers(HeaderUtil.createEntityDeletionAlert(ENTITY_NAME, id.toString())).build();
+    }
+
+}

jhipster/src/main/java/com/baeldung/web/rest/JWTToken.java

@@ -0,0 +1,24 @@
+package com.baeldung.web.rest;
+
+import com.fasterxml.jackson.annotation.JsonProperty;
+
+/**
+ * Object to return as body in JWT Authentication.
+ */
+public class JWTToken {
+
+    private String idToken;
+
+    public JWTToken(String idToken) {
+        this.idToken = idToken;
+    }
+
+    @JsonProperty("id_token")
+    public String getIdToken() {
+        return idToken;
+    }
+
+    public void setIdToken(String idToken) {
+        this.idToken = idToken;
+    }
+}

jhipster/src/main/java/com/baeldung/web/rest/LogsResource.java

@@ -0,0 +1,39 @@
+package com.baeldung.web.rest;
+
+import com.baeldung.web.rest.vm.LoggerVM;
+
+import ch.qos.logback.classic.Level;
+import ch.qos.logback.classic.LoggerContext;
+import com.codahale.metrics.annotation.Timed;
+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")
+    @Timed
+    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)
+    @Timed
+    public void changeLevel(@RequestBody LoggerVM jsonLogger) {
+        LoggerContext context = (LoggerContext) LoggerFactory.getILoggerFactory();
+        context.getLogger(jsonLogger.getName()).setLevel(Level.valueOf(jsonLogger.getLevel()));
+    }
+}

jhipster/src/main/java/com/baeldung/web/rest/PostResource.java

@@ -0,0 +1,129 @@
+package com.baeldung.web.rest;
+
+import com.codahale.metrics.annotation.Timed;
+import com.baeldung.domain.Post;
+
+import com.baeldung.repository.PostRepository;
+import com.baeldung.web.rest.util.HeaderUtil;
+import com.baeldung.web.rest.util.PaginationUtil;
+import io.swagger.annotations.ApiParam;
+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.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 Post.
+ */
+@RestController
+@RequestMapping("/api")
+public class PostResource {
+
+    private final Logger log = LoggerFactory.getLogger(PostResource.class);
+
+    private static final String ENTITY_NAME = "post";
+        
+    private final PostRepository postRepository;
+
+    public PostResource(PostRepository postRepository) {
+        this.postRepository = postRepository;
+    }
+
+    /**
+     * POST  /posts : Create a new post.
+     *
+     * @param post the post to create
+     * @return the ResponseEntity with status 201 (Created) and with body the new post, or with status 400 (Bad Request) if the post has already an ID
+     * @throws URISyntaxException if the Location URI syntax is incorrect
+     */
+    @PostMapping("/posts")
+    @Timed
+    public ResponseEntity<Post> createPost(@Valid @RequestBody Post post) throws URISyntaxException {
+        log.debug("REST request to save Post : {}", post);
+        if (post.getId() != null) {
+            return ResponseEntity.badRequest().headers(HeaderUtil.createFailureAlert(ENTITY_NAME, "idexists", "A new post cannot already have an ID")).body(null);
+        }
+        Post result = postRepository.save(post);
+        return ResponseEntity.created(new URI("/api/posts/" + result.getId()))
+            .headers(HeaderUtil.createEntityCreationAlert(ENTITY_NAME, result.getId().toString()))
+            .body(result);
+    }
+
+    /**
+     * PUT  /posts : Updates an existing post.
+     *
+     * @param post the post to update
+     * @return the ResponseEntity with status 200 (OK) and with body the updated post,
+     * or with status 400 (Bad Request) if the post is not valid,
+     * or with status 500 (Internal Server Error) if the post couldnt be updated
+     * @throws URISyntaxException if the Location URI syntax is incorrect
+     */
+    @PutMapping("/posts")
+    @Timed
+    public ResponseEntity<Post> updatePost(@Valid @RequestBody Post post) throws URISyntaxException {
+        log.debug("REST request to update Post : {}", post);
+        if (post.getId() == null) {
+            return createPost(post);
+        }
+        Post result = postRepository.save(post);
+        return ResponseEntity.ok()
+            .headers(HeaderUtil.createEntityUpdateAlert(ENTITY_NAME, post.getId().toString()))
+            .body(result);
+    }
+
+    /**
+     * GET  /posts : get all the posts.
+     *
+     * @param pageable the pagination information
+     * @return the ResponseEntity with status 200 (OK) and the list of posts in body
+     * @throws URISyntaxException if there is an error to generate the pagination HTTP headers
+     */
+    @GetMapping("/posts")
+    @Timed
+    public ResponseEntity<List<Post>> getAllPosts(@ApiParam Pageable pageable) {
+        log.debug("REST request to get a page of Posts");
+        Page<Post> page = postRepository.findAll(pageable);
+        HttpHeaders headers = PaginationUtil.generatePaginationHttpHeaders(page, "/api/posts");
+        return new ResponseEntity<>(page.getContent(), headers, HttpStatus.OK);
+    }
+
+    /**
+     * GET  /posts/:id : get the "id" post.
+     *
+     * @param id the id of the post to retrieve
+     * @return the ResponseEntity with status 200 (OK) and with body the post, or with status 404 (Not Found)
+     */
+    @GetMapping("/posts/{id}")
+    @Timed
+    public ResponseEntity<Post> getPost(@PathVariable Long id) {
+        log.debug("REST request to get Post : {}", id);
+        Post post = postRepository.findOne(id);
+        return ResponseUtil.wrapOrNotFound(Optional.ofNullable(post));
+    }
+
+    /**
+     * DELETE  /posts/:id : delete the "id" post.
+     *
+     * @param id the id of the post to delete
+     * @return the ResponseEntity with status 200 (OK)
+     */
+    @DeleteMapping("/posts/{id}")
+    @Timed
+    public ResponseEntity<Void> deletePost(@PathVariable Long id) {
+        log.debug("REST request to delete Post : {}", id);
+        postRepository.delete(id);
+        return ResponseEntity.ok().headers(HeaderUtil.createEntityDeletionAlert(ENTITY_NAME, id.toString())).build();
+    }
+
+}

jhipster/src/main/java/com/baeldung/web/rest/ProfileInfoResource.java

@@ -0,0 +1,69 @@
+package com.baeldung.web.rest;
+
+import com.baeldung.config.DefaultProfileUtil;
+
+import io.github.jhipster.config.JHipsterProperties;
+
+import org.springframework.core.env.Environment;
+import org.springframework.web.bind.annotation.*;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+
+/**
+ * Resource to return information about the currently running Spring profiles.
+ */
+@RestController
+@RequestMapping("/api")
+public class ProfileInfoResource {
+
+    private final Environment env;
+
+    private final JHipsterProperties jHipsterProperties;
+
+    public ProfileInfoResource(Environment env, JHipsterProperties jHipsterProperties) {
+        this.env = env;
+        this.jHipsterProperties = jHipsterProperties;
+    }
+
+    @GetMapping("/profile-info")
+    public ProfileInfoVM getActiveProfiles() {
+        String[] activeProfiles = DefaultProfileUtil.getActiveProfiles(env);
+        return new ProfileInfoVM(activeProfiles, getRibbonEnv(activeProfiles));
+    }
+
+    private String getRibbonEnv(String[] activeProfiles) {
+        String[] displayOnActiveProfiles = jHipsterProperties.getRibbon().getDisplayOnActiveProfiles();
+        if (displayOnActiveProfiles == null) {
+            return null;
+        }
+        List<String> ribbonProfiles = new ArrayList<>(Arrays.asList(displayOnActiveProfiles));
+        List<String> springBootProfiles = Arrays.asList(activeProfiles);
+        ribbonProfiles.retainAll(springBootProfiles);
+        if (!ribbonProfiles.isEmpty()) {
+            return ribbonProfiles.get(0);
+        }
+        return null;
+    }
+
+    class ProfileInfoVM {
+
+        private String[] activeProfiles;
+
+        private String ribbonEnv;
+
+        ProfileInfoVM(String[] activeProfiles, String ribbonEnv) {
+            this.activeProfiles = activeProfiles;
+            this.ribbonEnv = ribbonEnv;
+        }
+
+        public String[] getActiveProfiles() {
+            return activeProfiles;
+        }
+
+        public String getRibbonEnv() {
+            return ribbonEnv;
+        }
+    }
+}

jhipster/src/main/java/com/baeldung/web/rest/UserJWTController.java

@@ -0,0 +1,60 @@
+package com.baeldung.web.rest;
+
+import com.baeldung.security.jwt.JWTConfigurer;
+import com.baeldung.security.jwt.TokenProvider;
+import com.baeldung.web.rest.vm.LoginVM;
+
+import java.util.Collections;
+
+import com.codahale.metrics.annotation.Timed;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+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.AuthenticationException;
+import org.springframework.security.core.context.SecurityContextHolder;
+import org.springframework.web.bind.annotation.*;
+
+import javax.servlet.http.HttpServletResponse;
+import javax.validation.Valid;
+
+@RestController
+@RequestMapping("/api")
+public class UserJWTController {
+
+    private final Logger log = LoggerFactory.getLogger(UserJWTController.class);
+
+    private final TokenProvider tokenProvider;
+
+    private final AuthenticationManager authenticationManager;
+
+    public UserJWTController(TokenProvider tokenProvider, AuthenticationManager authenticationManager) {
+        this.tokenProvider = tokenProvider;
+        this.authenticationManager = authenticationManager;
+    }
+
+    @PostMapping("/authenticate")
+    @Timed
+    public ResponseEntity authorize(@Valid @RequestBody LoginVM loginVM, HttpServletResponse response) {
+
+        UsernamePasswordAuthenticationToken authenticationToken =
+            new UsernamePasswordAuthenticationToken(loginVM.getUsername(), loginVM.getPassword());
+
+        try {
+            Authentication authentication = this.authenticationManager.authenticate(authenticationToken);
+            SecurityContextHolder.getContext().setAuthentication(authentication);
+            boolean rememberMe = (loginVM.isRememberMe() == null) ? false : loginVM.isRememberMe();
+            String jwt = tokenProvider.createToken(authentication, rememberMe);
+            response.addHeader(JWTConfigurer.AUTHORIZATION_HEADER, "Bearer " + jwt);
+            return ResponseEntity.ok(new JWTToken(jwt));
+        } catch (AuthenticationException ae) {
+            log.trace("Authentication exception trace: {}", ae);
+            return new ResponseEntity<>(Collections.singletonMap("AuthenticationException",
+                ae.getLocalizedMessage()), HttpStatus.UNAUTHORIZED);
+        }
+    }
+}

jhipster/src/main/java/com/baeldung/web/rest/UserResource.java

@@ -0,0 +1,187 @@
+package com.baeldung.web.rest;
+
+import com.baeldung.config.Constants;
+import com.codahale.metrics.annotation.Timed;
+import com.baeldung.domain.User;
+import com.baeldung.repository.UserRepository;
+import com.baeldung.security.AuthoritiesConstants;
+import com.baeldung.service.MailService;
+import com.baeldung.service.UserService;
+import com.baeldung.service.dto.UserDTO;
+import com.baeldung.web.rest.vm.ManagedUserVM;
+import com.baeldung.web.rest.util.HeaderUtil;
+import com.baeldung.web.rest.util.PaginationUtil;
+import io.github.jhipster.web.util.ResponseUtil;
+import io.swagger.annotations.ApiParam;
+
+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.annotation.Secured;
+import org.springframework.web.bind.annotation.*;
+
+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>
+ * <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>
+ * <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.</p>
+ */
+@RestController
+@RequestMapping("/api")
+public class UserResource {
+
+    private final Logger log = LoggerFactory.getLogger(UserResource.class);
+
+    private static final String ENTITY_NAME = "userManagement";
+
+    private final UserRepository userRepository;
+
+    private final MailService mailService;
+
+    private final UserService userService;
+
+    public UserResource(UserRepository userRepository, MailService mailService,
+            UserService userService) {
+
+        this.userRepository = userRepository;
+        this.mailService = mailService;
+        this.userService = userService;
+    }
+
+    /**
+     * 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.
+     * </p>
+     *
+     * @param managedUserVM 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
+     */
+    @PostMapping("/users")
+    @Timed
+    @Secured(AuthoritiesConstants.ADMIN)
+    public ResponseEntity createUser(@RequestBody ManagedUserVM managedUserVM) throws URISyntaxException {
+        log.debug("REST request to save User : {}", managedUserVM);
+
+        if (managedUserVM.getId() != null) {
+            return ResponseEntity.badRequest()
+                .headers(HeaderUtil.createFailureAlert(ENTITY_NAME, "idexists", "A new user cannot already have an ID"))
+                .body(null);
+        // Lowercase the user login before comparing with database
+        } else if (userRepository.findOneByLogin(managedUserVM.getLogin().toLowerCase()).isPresent()) {
+            return ResponseEntity.badRequest()
+                .headers(HeaderUtil.createFailureAlert(ENTITY_NAME, "userexists", "Login already in use"))
+                .body(null);
+        } else if (userRepository.findOneByEmail(managedUserVM.getEmail()).isPresent()) {
+            return ResponseEntity.badRequest()
+                .headers(HeaderUtil.createFailureAlert(ENTITY_NAME, "emailexists", "Email already in use"))
+                .body(null);
+        } else {
+            User newUser = userService.createUser(managedUserVM);
+            mailService.sendCreationEmail(newUser);
+            return ResponseEntity.created(new URI("/api/users/" + newUser.getLogin()))
+                .headers(HeaderUtil.createAlert( "userManagement.created", newUser.getLogin()))
+                .body(newUser);
+        }
+    }
+
+    /**
+     * PUT  /users : Updates an existing User.
+     *
+     * @param managedUserVM the user to update
+     * @return the ResponseEntity with status 200 (OK) and with body the updated user,
+     * or with status 400 (Bad Request) if the login or email is already in use,
+     * or with status 500 (Internal Server Error) if the user couldn't be updated
+     */
+    @PutMapping("/users")
+    @Timed
+    @Secured(AuthoritiesConstants.ADMIN)
+    public ResponseEntity<UserDTO> updateUser(@RequestBody ManagedUserVM managedUserVM) {
+        log.debug("REST request to update User : {}", managedUserVM);
+        Optional<User> existingUser = userRepository.findOneByEmail(managedUserVM.getEmail());
+        if (existingUser.isPresent() && (!existingUser.get().getId().equals(managedUserVM.getId()))) {
+            return ResponseEntity.badRequest().headers(HeaderUtil.createFailureAlert(ENTITY_NAME, "emailexists", "E-mail already in use")).body(null);
+        }
+        existingUser = userRepository.findOneByLogin(managedUserVM.getLogin().toLowerCase());
+        if (existingUser.isPresent() && (!existingUser.get().getId().equals(managedUserVM.getId()))) {
+            return ResponseEntity.badRequest().headers(HeaderUtil.createFailureAlert(ENTITY_NAME, "userexists", "Login already in use")).body(null);
+        }
+        Optional<UserDTO> updatedUser = userService.updateUser(managedUserVM);
+
+        return ResponseUtil.wrapOrNotFound(updatedUser,
+            HeaderUtil.createAlert("userManagement.updated", managedUserVM.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")
+    @Timed
+    public ResponseEntity<List<UserDTO>> getAllUsers(@ApiParam Pageable pageable) {
+        final Page<UserDTO> page = userService.getAllManagedUsers(pageable);
+        HttpHeaders headers = PaginationUtil.generatePaginationHttpHeaders(page, "/api/users");
+        return new ResponseEntity<>(page.getContent(), headers, HttpStatus.OK);
+    }
+
+    /**
+     * 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 + "}")
+    @Timed
+    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 + "}")
+    @Timed
+    @Secured(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( "userManagement.deleted", login)).build();
+    }
+}

jhipster/src/main/java/com/baeldung/web/rest/errors/CustomParameterizedException.java

@@ -0,0 +1,34 @@
+package com.baeldung.web.rest.errors;
+
+/**
+ * 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 {{params[0]}} to {{params[1]}}"
+ * </pre>
+ */
+public class CustomParameterizedException extends RuntimeException {
+
+    private static final long serialVersionUID = 1L;
+
+    private final String message;
+    private final String[] params;
+
+    public CustomParameterizedException(String message, String... params) {
+        super(message);
+        this.message = message;
+        this.params = params;
+    }
+
+    public ParameterizedErrorVM getErrorVM() {
+        return new ParameterizedErrorVM(message, params);
+    }
+
+}

jhipster/src/main/java/com/baeldung/web/rest/errors/ErrorConstants.java

@@ -0,0 +1,14 @@
+package com.baeldung.web.rest.errors;
+
+public final class ErrorConstants {
+
+    public static final String ERR_CONCURRENCY_FAILURE = "error.concurrencyFailure";
+    public static final String ERR_ACCESS_DENIED = "error.accessDenied";
+    public static final String ERR_VALIDATION = "error.validation";
+    public static final String ERR_METHOD_NOT_SUPPORTED = "error.methodNotSupported";
+    public static final String ERR_INTERNAL_SERVER_ERROR = "error.internalServerError";
+
+    private ErrorConstants() {
+    }
+
+}

jhipster/src/main/java/com/baeldung/web/rest/errors/ErrorVM.java

@@ -0,0 +1,52 @@
+package com.baeldung.web.rest.errors;
+
+import java.io.Serializable;
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * View Model for transferring error message with a list of field errors.
+ */
+public class ErrorVM implements Serializable {
+
+    private static final long serialVersionUID = 1L;
+
+    private final String message;
+    private final String description;
+
+    private List<FieldErrorVM> fieldErrors;
+
+    public ErrorVM(String message) {
+        this(message, null);
+    }
+
+    public ErrorVM(String message, String description) {
+        this.message = message;
+        this.description = description;
+    }
+
+    public ErrorVM(String message, String description, List<FieldErrorVM> fieldErrors) {
+        this.message = message;
+        this.description = description;
+        this.fieldErrors = fieldErrors;
+    }
+
+    public void add(String objectName, String field, String message) {
+        if (fieldErrors == null) {
+            fieldErrors = new ArrayList<>();
+        }
+        fieldErrors.add(new FieldErrorVM(objectName, field, message));
+    }
+
+    public String getMessage() {
+        return message;
+    }
+
+    public String getDescription() {
+        return description;
+    }
+
+    public List<FieldErrorVM> getFieldErrors() {
+        return fieldErrors;
+    }
+}

jhipster/src/main/java/com/baeldung/web/rest/errors/ExceptionTranslator.java

@@ -0,0 +1,85 @@
+package com.baeldung.web.rest.errors;
+
+import java.util.List;
+
+import org.springframework.core.annotation.AnnotationUtils;
+import org.springframework.dao.ConcurrencyFailureException;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseEntity;
+import org.springframework.http.ResponseEntity.BodyBuilder;
+import org.springframework.security.access.AccessDeniedException;
+import org.springframework.validation.BindingResult;
+import org.springframework.validation.FieldError;
+import org.springframework.web.HttpRequestMethodNotSupportedException;
+import org.springframework.web.bind.MethodArgumentNotValidException;
+import org.springframework.web.bind.annotation.*;
+
+/**
+ * Controller advice to translate the server side exceptions to client-friendly json structures.
+ */
+@ControllerAdvice
+public class ExceptionTranslator {
+
+    @ExceptionHandler(ConcurrencyFailureException.class)
+    @ResponseStatus(HttpStatus.CONFLICT)
+    @ResponseBody
+    public ErrorVM processConcurrencyError(ConcurrencyFailureException ex) {
+        return new ErrorVM(ErrorConstants.ERR_CONCURRENCY_FAILURE);
+    }
+
+    @ExceptionHandler(MethodArgumentNotValidException.class)
+    @ResponseStatus(HttpStatus.BAD_REQUEST)
+    @ResponseBody
+    public ErrorVM processValidationError(MethodArgumentNotValidException ex) {
+        BindingResult result = ex.getBindingResult();
+        List<FieldError> fieldErrors = result.getFieldErrors();
+
+        return processFieldErrors(fieldErrors);
+    }
+
+    @ExceptionHandler(CustomParameterizedException.class)
+    @ResponseStatus(HttpStatus.BAD_REQUEST)
+    @ResponseBody
+    public ParameterizedErrorVM processParameterizedValidationError(CustomParameterizedException ex) {
+        return ex.getErrorVM();
+    }
+
+    @ExceptionHandler(AccessDeniedException.class)
+    @ResponseStatus(HttpStatus.FORBIDDEN)
+    @ResponseBody
+    public ErrorVM processAccessDeniedException(AccessDeniedException e) {
+        return new ErrorVM(ErrorConstants.ERR_ACCESS_DENIED, e.getMessage());
+    }
+
+    private ErrorVM processFieldErrors(List<FieldError> fieldErrors) {
+        ErrorVM dto = new ErrorVM(ErrorConstants.ERR_VALIDATION);
+
+        for (FieldError fieldError : fieldErrors) {
+            dto.add(fieldError.getObjectName(), fieldError.getField(), fieldError.getCode());
+        }
+
+        return dto;
+    }
+
+    @ExceptionHandler(HttpRequestMethodNotSupportedException.class)
+    @ResponseBody
+    @ResponseStatus(HttpStatus.METHOD_NOT_ALLOWED)
+    public ErrorVM processMethodNotSupportedException(HttpRequestMethodNotSupportedException exception) {
+        return new ErrorVM(ErrorConstants.ERR_METHOD_NOT_SUPPORTED, exception.getMessage());
+    }
+
+    @ExceptionHandler(Exception.class)
+    public ResponseEntity<ErrorVM> processRuntimeException(Exception ex) {
+        BodyBuilder builder;
+        ErrorVM errorVM;
+        ResponseStatus responseStatus = AnnotationUtils.findAnnotation(ex.getClass(), ResponseStatus.class);
+        if (responseStatus != null) {
+            builder = ResponseEntity.status(responseStatus.value());
+            errorVM = new ErrorVM("error." + responseStatus.value().value(), responseStatus.reason());
+        } else {
+            builder = ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR);
+            errorVM = new ErrorVM(ErrorConstants.ERR_INTERNAL_SERVER_ERROR, "Internal server error");
+        }
+        return builder.body(errorVM);
+    }
+}

jhipster/src/main/java/com/baeldung/web/rest/errors/FieldErrorVM.java

@@ -0,0 +1,33 @@
+package com.baeldung.web.rest.errors;
+
+import java.io.Serializable;
+
+public class FieldErrorVM implements Serializable {
+
+    private static final long serialVersionUID = 1L;
+
+    private final String objectName;
+
+    private final String field;
+
+    private final String message;
+
+    public FieldErrorVM(String dto, String field, String message) {
+        this.objectName = dto;
+        this.field = field;
+        this.message = message;
+    }
+
+    public String getObjectName() {
+        return objectName;
+    }
+
+    public String getField() {
+        return field;
+    }
+
+    public String getMessage() {
+        return message;
+    }
+
+}

jhipster/src/main/java/com/baeldung/web/rest/errors/ParameterizedErrorVM.java

@@ -0,0 +1,27 @@
+package com.baeldung.web.rest.errors;
+
+import java.io.Serializable;
+
+/**
+ * View Model for sending a parameterized error message.
+ */
+public class ParameterizedErrorVM implements Serializable {
+
+    private static final long serialVersionUID = 1L;
+    private final String message;
+    private final String[] params;
+
+    public ParameterizedErrorVM(String message, String... params) {
+        this.message = message;
+        this.params = params;
+    }
+
+    public String getMessage() {
+        return message;
+    }
+
+    public String[] getParams() {
+        return params;
+    }
+
+}

jhipster/src/main/java/com/baeldung/web/rest/package-info.java

@@ -0,0 +1,4 @@
+/**
+ * Spring MVC REST controllers.
+ */
+package com.baeldung.web.rest;

jhipster/src/main/java/com/baeldung/web/rest/util/HeaderUtil.java

@@ -0,0 +1,45 @@
+package com.baeldung.web.rest.util;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.http.HttpHeaders;
+
+/**
+ * Utility class for HTTP headers creation.
+ */
+public final class HeaderUtil {
+
+    private static final Logger log = LoggerFactory.getLogger(HeaderUtil.class);
+
+    private static final String APPLICATION_NAME = "baeldungApp";
+
+    private HeaderUtil() {
+    }
+
+    public static HttpHeaders createAlert(String message, String param) {
+        HttpHeaders headers = new HttpHeaders();
+        headers.add("X-baeldungApp-alert", message);
+        headers.add("X-baeldungApp-params", param);
+        return headers;
+    }
+
+    public static HttpHeaders createEntityCreationAlert(String entityName, String param) {
+        return createAlert(APPLICATION_NAME + "." + entityName + ".created", param);
+    }
+
+    public static HttpHeaders createEntityUpdateAlert(String entityName, String param) {
+        return createAlert(APPLICATION_NAME + "." + entityName + ".updated", param);
+    }
+
+    public static HttpHeaders createEntityDeletionAlert(String entityName, String param) {
+        return createAlert(APPLICATION_NAME + "." + entityName + ".deleted", param);
+    }
+
+    public static HttpHeaders createFailureAlert(String entityName, String errorKey, String defaultMessage) {
+        log.error("Entity creation failed, {}", defaultMessage);
+        HttpHeaders headers = new HttpHeaders();
+        headers.add("X-baeldungApp-error", "error." + errorKey);
+        headers.add("X-baeldungApp-params", entityName);
+        return headers;
+    }
+}

jhipster/src/main/java/com/baeldung/web/rest/util/PaginationUtil.java

@@ -0,0 +1,47 @@
+package com.baeldung.web.rest.util;
+
+import org.springframework.data.domain.Page;
+import org.springframework.http.HttpHeaders;
+import org.springframework.web.util.UriComponentsBuilder;
+
+import java.net.URISyntaxException;
+
+/**
+ * Utility class for handling pagination.
+ *
+ * <p>
+ * Pagination uses the same principles as the <a href="https://developer.github.com/v3/#pagination">Github API</a>,
+ * and follow <a href="http://tools.ietf.org/html/rfc5988">RFC 5988 (Link header)</a>.
+ */
+public final class PaginationUtil {
+
+    private PaginationUtil() {
+    }
+
+    public static HttpHeaders generatePaginationHttpHeaders(Page page, String baseUrl) {
+
+        HttpHeaders headers = new HttpHeaders();
+        headers.add("X-Total-Count", "" + Long.toString(page.getTotalElements()));
+        String link = "";
+        if ((page.getNumber() + 1) < page.getTotalPages()) {
+            link = "<" + generateUri(baseUrl, page.getNumber() + 1, page.getSize()) + ">; rel=\"next\",";
+        }
+        // prev link
+        if ((page.getNumber()) > 0) {
+            link += "<" + generateUri(baseUrl, page.getNumber() - 1, page.getSize()) + ">; rel=\"prev\",";
+        }
+        // last and first link
+        int lastPage = 0;
+        if (page.getTotalPages() > 0) {
+            lastPage = page.getTotalPages() - 1;
+        }
+        link += "<" + generateUri(baseUrl, lastPage, page.getSize()) + ">; rel=\"last\",";
+        link += "<" + generateUri(baseUrl, 0, page.getSize()) + ">; rel=\"first\"";
+        headers.add(HttpHeaders.LINK, link);
+        return headers;
+    }
+
+    private static String generateUri(String baseUrl, int page, int size) {
+        return UriComponentsBuilder.fromUriString(baseUrl).queryParam("page", page).queryParam("size", size).toUriString();
+    }
+}

jhipster/src/main/java/com/baeldung/web/rest/vm/KeyAndPasswordVM.java

@@ -0,0 +1,27 @@
+package com.baeldung.web.rest.vm;
+
+/**
+ * View Model object for storing the user's key and password.
+ */
+public class KeyAndPasswordVM {
+
+    private String key;
+
+    private String newPassword;
+
+    public String getKey() {
+        return key;
+    }
+
+    public void setKey(String key) {
+        this.key = key;
+    }
+
+    public String getNewPassword() {
+        return newPassword;
+    }
+
+    public void setNewPassword(String newPassword) {
+        this.newPassword = newPassword;
+    }
+}

jhipster/src/main/java/com/baeldung/web/rest/vm/LoggerVM.java

@@ -0,0 +1,48 @@
+package com.baeldung.web.rest.vm;
+
+import ch.qos.logback.classic.Logger;
+import com.fasterxml.jackson.annotation.JsonCreator;
+
+/**
+ * View Model object for storing a Logback logger.
+ */
+public class LoggerVM {
+
+    private String name;
+
+    private String level;
+
+    public LoggerVM(Logger logger) {
+        this.name = logger.getName();
+        this.level = logger.getEffectiveLevel().toString();
+    }
+
+    @JsonCreator
+    public LoggerVM() {
+        // Empty public constructor used by Jackson.
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public String getLevel() {
+        return level;
+    }
+
+    public void setLevel(String level) {
+        this.level = level;
+    }
+
+    @Override
+    public String toString() {
+        return "LoggerVM{" +
+            "name='" + name + '\'' +
+            ", level='" + level + '\'' +
+            '}';
+    }
+}

jhipster/src/main/java/com/baeldung/web/rest/vm/LoginVM.java

@@ -0,0 +1,55 @@
+package com.baeldung.web.rest.vm;
+
+import com.baeldung.config.Constants;
+import javax.validation.constraints.NotNull;
+import javax.validation.constraints.Pattern;
+import javax.validation.constraints.Size;
+
+/**
+ * View Model object for storing a user's credentials.
+ */
+public class LoginVM {
+
+    @Pattern(regexp = Constants.LOGIN_REGEX)
+    @NotNull
+    @Size(min = 1, max = 50)
+    private String username;
+
+    @NotNull
+    @Size(min = ManagedUserVM.PASSWORD_MIN_LENGTH, max = ManagedUserVM.PASSWORD_MAX_LENGTH)
+    private String password;
+
+    private Boolean rememberMe;
+
+    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;
+    }
+
+    public Boolean isRememberMe() {
+        return rememberMe;
+    }
+
+    public void setRememberMe(Boolean rememberMe) {
+        this.rememberMe = rememberMe;
+    }
+
+    @Override
+    public String toString() {
+        return "LoginVM{" +
+            "username='" + username + '\'' +
+            ", rememberMe=" + rememberMe +
+            '}';
+    }
+}

jhipster/src/main/java/com/baeldung/web/rest/vm/ManagedUserVM.java

@@ -0,0 +1,45 @@
+package com.baeldung.web.rest.vm;
+
+import com.baeldung.service.dto.UserDTO;
+import javax.validation.constraints.Size;
+
+import java.time.ZonedDateTime;
+import java.util.Set;
+
+/**
+ * View Model extending the UserDTO, which is meant to be used in the user management UI.
+ */
+public class ManagedUserVM extends UserDTO {
+
+    public static final int PASSWORD_MIN_LENGTH = 4;
+
+    public static final int PASSWORD_MAX_LENGTH = 100;
+
+    @Size(min = PASSWORD_MIN_LENGTH, max = PASSWORD_MAX_LENGTH)
+    private String password;
+
+    public ManagedUserVM() {
+        // Empty constructor needed for Jackson.
+    }
+
+    public ManagedUserVM(Long id, String login, String password, String firstName, String lastName,
+                         String email, boolean activated, String imageUrl, String langKey,
+                         String createdBy, ZonedDateTime createdDate, String lastModifiedBy, ZonedDateTime lastModifiedDate,
+                        Set<String> authorities) {
+
+        super(id, login, firstName, lastName, email, activated,  imageUrl, langKey,
+            createdBy, createdDate, lastModifiedBy, lastModifiedDate,  authorities);
+
+        this.password = password;
+    }
+
+    public String getPassword() {
+        return password;
+    }
+
+    @Override
+    public String toString() {
+        return "ManagedUserVM{" +
+            "} " + super.toString();
+    }
+}

jhipster/src/main/java/com/baeldung/web/rest/vm/package-info.java

@@ -0,0 +1,4 @@
+/**
+ * View Models used by Spring MVC REST controllers.
+ */
+package com.baeldung.web.rest.vm;

jhipster/src/main/resources/.h2.server.properties

@@ -0,0 +1,5 @@
+#H2 Server Properties
+0=JHipster H2 (Disk)|org.h2.Driver|jdbc\:h2\:file\:./target/h2db/db/baeldung|baeldung
+webAllowOthers=true
+webPort=8082
+webSSL=false