docs: update .all-contributorsrc [skip ci]

* docs: update README.md [skip ci]

* docs: update .all-contributorsrc [skip ci]

Co-authored-by: allcontributors[bot] <46447321+allcontributors[bot]@users.noreply.github.com>

.github/FUNDING.yml

@@ -0,0 +1 @@
+github: [iluwatar]

.github/workflows/maven.yml

@@ -0,0 +1,60 @@
+#
+# The MIT License
+# Copyright © 2014-2019 Ilkka Seppälä
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in
+# all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+# THE SOFTWARE.
+#
+
+# This workflow will build a Java project with Maven
+# For more information see: https://help.github.com/actions/language-and-framework-guides/building-and-testing-java-with-maven
+
+name: Java CI with Maven
+
+on:
+  push:
+    branches: [ master ]
+  pull_request:
+    branches: [ master ]
+
+jobs:
+  build:
+
+    runs-on: ubuntu-18.04
+
+    steps:
+    - uses: actions/checkout@v2
+    - name: Set up JDK 11
+      uses: actions/setup-java@v1
+      with:
+        java-version: 11
+    # Some tests need screen access
+    - name: Install xvfb
+      run: sudo apt-get install xvfb
+    # SonarQube scan does not work for forked repositories
+    # See https://jira.sonarsource.com/browse/MMF-1371
+    - name: Build with Maven
+      if: github.ref != 'refs/heads/master'
+      run: xvfb-run mvn clean verify
+    - name: Build with Maven and run SonarQube analysis
+      if: github.ref == 'refs/heads/master'
+      run: xvfb-run mvn clean verify org.sonarsource.scanner.maven:sonar-maven-plugin:sonar
+      env:
+        # These two env variables are needed for sonar analysis
+        GITHUB_TOKEN: ${{ secrets.REPOSITORY_ACCESS_TOKEN }}
+        SONAR_TOKEN: ${{ secrets.SONAR_TOKEN }}

.gitignore

@@ -16,5 +16,4 @@ datanucleus.log
 /bin/
 /bin/
 *.log
-data-mapper/src/main/resources/log4j.xml
 event-sourcing/Journal.json

.travis.yml

@@ -1,39 +0,0 @@
-language: java
-jdk:
-- oraclejdk8
-
-env:
-  global:
-  - GH_REF: github.com/iluwatar/java-design-patterns.git
-  - secure: LxTDuNS/rBWIvKkaEqr79ImZAe48mCdoYCF41coxNXgNoippo4GIBArknqtv+XvdkiuRZ1yGyj6pn8GU33c/yn+krddTUkVCwTbVatbalW5jhQjDbHYym/JcxaK9ZS/3JTeGcWrBgiPqHEEDhCf26vPZsXoMSeVCEORVKTp1BSg=
-  - secure: "eoWlW9GyTJY04P8K3pxayXwU9/hmptQg/LfirispQkV9YvmziCfSzXnatnBhNfud98sCzY8BScXnb+OWLTnjLKpId4rtEqb0aJ40Jc32cUKzgzFAUn7cNcDAbUIfyPAGVqyQqfj/11wYSADwWMMOPlW97ExUtoyiH2WenXuRHso="
-  
-before_install:
-- export DISPLAY=:99.0
-- sh -e /etc/init.d/xvfb start
-
-# default install command is just "mvn install -DskipTests=true -Dmaven.javadoc.skip=true -B -V"
-install:
-- mvn install -DskipTests=true -Dmaven.javadoc.skip=true -B -V -e
-
-after_success:
-- mvn clean org.jacoco:jacoco-maven-plugin:prepare-agent package sonar:sonar -Dsonar.host.url=https://sonarcloud.io -Dsonar.login=$SONAR_TOKEN
-- bash update-ghpages.sh
-
-# use latest java version available instead of travis default
-addons:
-  apt:
-    packages:
-      - oracle-java8-installer
-
-notifications:
-  email:
-    - iluwatar@gmail.com
-  webhooks:
-    urls:
-      - https://webhooks.gitter.im/e/3319623945358a093a6f
-    on_success: change  # options: [always|never|change] default: always
-    on_failure: always  # options: [always|never|change] default: always
-    on_start: never     # options: [always|never|change] default: always
-
-sudo: required

CODE_COVERAGE.md

@@ -1,13 +0,0 @@
-# Code Coverage Report generation
-
-To generate the code coverage report, execute the following command:
-> mvn clean verify jacoco:report
-
-This will generate code coverage report in each of the modules. In order to view the same, open the following file in your browser.
-> target/site/jacoco/index.html 
-
-Please note that the above folder is created under each of the modules. For example:
-* adapter/target/site/jacoco/index.html 
-* busniess-delegate/target/site/jacoco/index.html 
-
-

LICENSE.md

@@ -1,6 +1,6 @@
 The MIT License (MIT)
 
-Copyright (c) 2014-2016 Ilkka Seppälä
+Copyright (c) 2014-2020 Ilkka Seppälä
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal

README.md

@@ -4,44 +4,239 @@
 
 # Design patterns implemented in Java
 
-[![Build status](https://travis-ci.org/iluwatar/java-design-patterns.svg?branch=master)](https://travis-ci.org/iluwatar/java-design-patterns)
+![Java CI with Maven](https://github.com/iluwatar/java-design-patterns/workflows/Java%20CI%20with%20Maven/badge.svg)
 [![License MIT](https://img.shields.io/badge/license-MIT-blue.svg)](https://raw.githubusercontent.com/iluwatar/java-design-patterns/master/LICENSE.md)
 [![Join the chat at https://gitter.im/iluwatar/java-design-patterns](https://badges.gitter.im/Join%20Chat.svg)](https://gitter.im/iluwatar/java-design-patterns?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge)
-[![Quality Gate](https://sonarcloud.io/api/project_badges/measure?project=com.iluwatar%3Ajava-design-patterns&metric=alert_status)](https://sonarcloud.io/dashboard/index/com.iluwatar%3Ajava-design-patterns)
+[![Sonarcloud Status](https://sonarcloud.io/api/project_badges/measure?project=iluwatar_java-design-patterns&metric=alert_status)](https://sonarcloud.io/dashboard?id=iluwatar_java-design-patterns) 
+<!-- ALL-CONTRIBUTORS-BADGE:START - Do not remove or modify this section -->
+[![All Contributors](https://img.shields.io/badge/all_contributors-111-orange.svg?style=flat-square)](#contributors-)
+<!-- ALL-CONTRIBUTORS-BADGE:END -->
 
 # Introduction
 
-Design patterns are formalized best practices that the programmer can use to
+Design patterns are the best formalized practices a programmer can use to
 solve common problems when designing an application or system.
 
 Design patterns can speed up the development process by providing tested, proven
 development paradigms.
 
-Reusing design patterns helps to prevent subtle issues that can cause major
+Reusing design patterns help prevent subtle issues that cause major
 problems, and it also improves code readability for coders and architects who
 are familiar with the patterns.
 
 # Getting started
 
+This site showcases Java Design Patterns. The solutions have been developed by
+experienced programmers and architects from the open source community. The 
+patterns can be browsed by their high level descriptions or by looking at their
+source code. The source code examples are well commented and can be thought as
+programming tutorials how to implement a specific pattern. We use the most
+popular battle-proven open source Java technologies.
+
 Before you dive into the material, you should be familiar with various
-Programming/Software Design Principles.
+[Software Design Principles](https://java-design-patterns.com/principles/).
 
 All designs should be as simple as possible. You should start with KISS, YAGNI,
 and Do The Simplest Thing That Could Possibly Work principles. Complexity and
 patterns should only be introduced when they are needed for practical
 extensibility.
 
-Once you are familiar with these concepts you can start drilling down into
-patterns by any of the following approaches
+Once you are familiar with these concepts you can start drilling down into the
+[available design patterns](https://java-design-patterns.com/patterns/) by any 
+of the following approaches
 
- - Using difficulty tags, `Difficulty-Beginner`, `Difficulty-Intermediate` & `Difficulty-Expert`.
- - Using pattern categories, `Creational`, `Behavioral` and others.
- - Search for a specific pattern. Can't find one? Please report a new pattern [here](https://github.com/iluwatar/java-design-patterns/issues).
+ - Search for a specific pattern by name. Can't find one? Please report a new pattern [here](https://github.com/iluwatar/java-design-patterns/issues).
+ - Using tags such as `Performance`, `Gang of Four` or `Data access`.
+ - Using pattern categories, `Creational`, `Behavioral`, and others.
+
+Hopefully you find the object oriented solutions presented on this site useful
+in your architectures and have as much fun learning them as we had developing them.
 
 # How to contribute
 
-If you are willing to contribute to the project you will find the relevant information in our [developer wiki](https://github.com/iluwatar/java-design-patterns/wiki). We will help you and answer your questions in the [Gitter chatroom](https://gitter.im/iluwatar/java-design-patterns).
+If you are willing to contribute to the project you will find the relevant information in 
+our [developer wiki](https://github.com/iluwatar/java-design-patterns/wiki). We will help 
+you and answer your questions in the [Gitter chatroom](https://gitter.im/iluwatar/java-design-patterns).
 
 # License
 
 This project is licensed under the terms of the MIT license.
+
+# Contributors
+
+<!-- ALL-CONTRIBUTORS-LIST:START - Do not remove or modify this section -->
+<!-- prettier-ignore-start -->
+<!-- markdownlint-disable -->
+<table>
+  <tr>
+    <td align="center"><a href="https://github.com/iluwatar"><img src="https://avatars1.githubusercontent.com/u/582346?v=4" width="100px;" alt=""/><br /><sub><b>Ilkka Seppälä</b></sub></a><br /><a href="#projectManagement-iluwatar" title="Project Management">📆</a> <a href="#maintenance-iluwatar" title="Maintenance">🚧</a> <a href="#content-iluwatar" title="Content">🖋</a></td>
+    <td align="center"><a href="https://github.com/amit1307"><img src="https://avatars0.githubusercontent.com/u/23420222?v=4" width="100px;" alt=""/><br /><sub><b>amit1307</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=amit1307" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/npathai"><img src="https://avatars2.githubusercontent.com/u/1792515?v=4" width="100px;" alt=""/><br /><sub><b>Narendra Pathai</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=npathai" title="Code">💻</a> <a href="#ideas-npathai" title="Ideas, Planning, & Feedback">🤔</a> <a href="https://github.com/iluwatar/java-design-patterns/pulls?q=is%3Apr+reviewed-by%3Anpathai" title="Reviewed Pull Requests">👀</a></td>
+    <td align="center"><a href="https://github.com/fluxw42"><img src="https://avatars1.githubusercontent.com/u/1545460?v=4" width="100px;" alt=""/><br /><sub><b>Jeroen Meulemeester</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=fluxw42" title="Code">💻</a></td>
+  </tr>
+  <tr>
+    <td align="center"><a href="http://www.joemccarthy.co.uk"><img src="https://avatars0.githubusercontent.com/u/4526195?v=4" width="100px;" alt=""/><br /><sub><b>Joseph McCarthy</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=mikulucky" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/thomasoss"><img src="https://avatars1.githubusercontent.com/u/22516154?v=4" width="100px;" alt=""/><br /><sub><b>Thomas</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=thomasoss" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/anuragagarwal561994"><img src="https://avatars1.githubusercontent.com/u/6075379?v=4" width="100px;" alt=""/><br /><sub><b>Anurag Agarwal</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=anuragagarwal561994" title="Code">💻</a></td>
+    <td align="center"><a href="https://markusmo3.github.io"><img src="https://avatars1.githubusercontent.com/u/3317416?v=4" width="100px;" alt=""/><br /><sub><b>Markus Moser</b></sub></a><br /><a href="#design-markusmo3" title="Design">🎨</a> <a href="https://github.com/iluwatar/java-design-patterns/commits?author=markusmo3" title="Code">💻</a> <a href="#ideas-markusmo3" title="Ideas, Planning, & Feedback">🤔</a></td>
+  </tr>
+  <tr>
+    <td align="center"><a href="https://twitter.com/i_sabiq"><img src="https://avatars1.githubusercontent.com/u/19510920?v=4" width="100px;" alt=""/><br /><sub><b>Sabiq Ihab</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=isabiq" title="Code">💻</a></td>
+    <td align="center"><a href="http://inbravo.github.io"><img src="https://avatars3.githubusercontent.com/u/5253764?v=4" width="100px;" alt=""/><br /><sub><b>Amit Dixit</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=inbravo" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/piyushchaudhari04"><img src="https://avatars3.githubusercontent.com/u/10268029?v=4" width="100px;" alt=""/><br /><sub><b>Piyush Kailash Chaudhari</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=piyushchaudhari04" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/joshzambales"><img src="https://avatars1.githubusercontent.com/u/8704552?v=4" width="100px;" alt=""/><br /><sub><b>joshzambales</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=joshzambales" title="Code">💻</a></td>
+  </tr>
+  <tr>
+    <td align="center"><a href="https://github.com/Crossy147"><img src="https://avatars2.githubusercontent.com/u/7272996?v=4" width="100px;" alt=""/><br /><sub><b>Kamil Pietruszka</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=Crossy147" title="Code">💻</a></td>
+    <td align="center"><a href="http://cs.joensuu.fi/~zkhayda"><img src="https://avatars2.githubusercontent.com/u/660742?v=4" width="100px;" alt=""/><br /><sub><b>Zafar Khaydarov</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=zafarella" title="Code">💻</a> <a href="https://github.com/iluwatar/java-design-patterns/commits?author=zafarella" title="Documentation">📖</a></td>
+    <td align="center"><a href="https://kemitix.github.io/"><img src="https://avatars1.githubusercontent.com/u/1147749?v=4" width="100px;" alt=""/><br /><sub><b>Paul Campbell</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=kemitix" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/Argyro-Sioziou"><img src="https://avatars0.githubusercontent.com/u/22822639?v=4" width="100px;" alt=""/><br /><sub><b>Argyro Sioziou</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=Argyro-Sioziou" title="Code">💻</a></td>
+  </tr>
+  <tr>
+    <td align="center"><a href="https://github.com/TylerMcConville"><img src="https://avatars0.githubusercontent.com/u/4946449?v=4" width="100px;" alt=""/><br /><sub><b>TylerMcConville</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=TylerMcConville" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/saksham93"><img src="https://avatars1.githubusercontent.com/u/37399540?v=4" width="100px;" alt=""/><br /><sub><b>saksham93</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=saksham93" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/nikhilbarar"><img src="https://avatars2.githubusercontent.com/u/37332144?v=4" width="100px;" alt=""/><br /><sub><b>nikhilbarar</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=nikhilbarar" title="Code">💻</a></td>
+    <td align="center"><a href="http://colinbut.com"><img src="https://avatars2.githubusercontent.com/u/10725674?v=4" width="100px;" alt=""/><br /><sub><b>Colin But</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=colinbut" title="Code">💻</a></td>
+  </tr>
+  <tr>
+    <td align="center"><a href="https://github.com/ruslanpa"><img src="https://avatars2.githubusercontent.com/u/1503411?v=4" width="100px;" alt=""/><br /><sub><b>Ruslan</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=ruslanpa" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/JuhoKang"><img src="https://avatars1.githubusercontent.com/u/4745294?v=4" width="100px;" alt=""/><br /><sub><b>Juho Kang</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=JuhoKang" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/dheeraj-mummareddy"><img src="https://avatars2.githubusercontent.com/u/7002230?v=4" width="100px;" alt=""/><br /><sub><b>Dheeraj Mummareddy</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=dheeraj-mummareddy" title="Code">💻</a></td>
+    <td align="center"><a href="https://www.bernardosulzbach.com"><img src="https://avatars0.githubusercontent.com/u/8271090?v=4" width="100px;" alt=""/><br /><sub><b>Bernardo Sulzbach</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=bernardosulzbach" title="Code">💻</a></td>
+  </tr>
+  <tr>
+    <td align="center"><a href="https://github.com/4lexis"><img src="https://avatars0.githubusercontent.com/u/19871727?v=4" width="100px;" alt=""/><br /><sub><b>Aleksandar Dudukovic</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=4lexis" title="Code">💻</a></td>
+    <td align="center"><a href="https://www.yusufaytas.com"><img src="https://avatars2.githubusercontent.com/u/1049483?v=4" width="100px;" alt=""/><br /><sub><b>Yusuf Aytaş</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=yusufaytas" title="Code">💻</a></td>
+    <td align="center"><a href="http://futurehomes.hu"><img src="https://avatars2.githubusercontent.com/u/1001491?v=4" width="100px;" alt=""/><br /><sub><b>Mihály Kuprivecz</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=qpi" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/kapinuss"><img src="https://avatars0.githubusercontent.com/u/17639945?v=4" width="100px;" alt=""/><br /><sub><b>Stanislav Kapinus</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=kapinuss" title="Code">💻</a></td>
+  </tr>
+  <tr>
+    <td align="center"><a href="https://github.com/gvsharma"><img src="https://avatars1.githubusercontent.com/u/6648152?v=4" width="100px;" alt=""/><br /><sub><b>GVSharma</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=gvsharma" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/SrdjanPaunovic"><img src="https://avatars1.githubusercontent.com/u/22815104?v=4" width="100px;" alt=""/><br /><sub><b>Srđan Paunović</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=SrdjanPaunovic" title="Code">💻</a></td>
+    <td align="center"><a href="https://sideris.xyz/"><img src="https://avatars3.githubusercontent.com/u/5484694?v=4" width="100px;" alt=""/><br /><sub><b>Petros G. Sideris</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=sideris" title="Code">💻</a></td>
+    <td align="center"><a href="https://www.linkedin.com/in/pramodgupta3/"><img src="https://avatars1.githubusercontent.com/u/2184241?v=4" width="100px;" alt=""/><br /><sub><b>Pramod Gupta</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/pulls?q=is%3Apr+reviewed-by%3AIAmPramod" title="Reviewed Pull Requests">👀</a></td>
+  </tr>
+  <tr>
+    <td align="center"><a href="https://amarnath510.github.io/portfolio"><img src="https://avatars0.githubusercontent.com/u/4599623?v=4" width="100px;" alt=""/><br /><sub><b>Amarnath Chandana</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=Amarnath510" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/Anurag870"><img src="https://avatars1.githubusercontent.com/u/6295975?v=4" width="100px;" alt=""/><br /><sub><b>Anurag870</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=Anurag870" title="Code">💻</a></td>
+    <td align="center"><a href="http://theerroris.me"><img src="https://avatars0.githubusercontent.com/u/1685953?v=4" width="100px;" alt=""/><br /><sub><b>Wes Gilleland</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=Deathnerd" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/Harshrajsinh"><img src="https://avatars2.githubusercontent.com/u/22811531?v=4" width="100px;" alt=""/><br /><sub><b>Harshraj Thakor</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=Harshrajsinh" title="Code">💻</a></td>
+  </tr>
+  <tr>
+    <td align="center"><a href="https://github.com/MaVdbussche"><img src="https://avatars1.githubusercontent.com/u/26136934?v=4" width="100px;" alt=""/><br /><sub><b>Martin Vandenbussche</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=MaVdbussche" title="Code">💻</a></td>
+    <td align="center"><a href="https://alexsomai.com"><img src="https://avatars1.githubusercontent.com/u/5720977?v=4" width="100px;" alt=""/><br /><sub><b>Alexandru Somai</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=alexsomai" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/amogozov"><img src="https://avatars3.githubusercontent.com/u/7372215?v=4" width="100px;" alt=""/><br /><sub><b>Artur Mogozov</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=amogozov" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/anthonycampbell"><img src="https://avatars3.githubusercontent.com/u/10249255?v=4" width="100px;" alt=""/><br /><sub><b>anthony</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=anthonycampbell" title="Code">💻</a></td>
+  </tr>
+  <tr>
+    <td align="center"><a href="http://ccygnus.com/"><img src="https://avatars1.githubusercontent.com/u/9342724?v=4" width="100px;" alt=""/><br /><sub><b>Christian Cygnus</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=christophercolumbusdog" title="Code">💻</a></td>
+    <td align="center"><a href="https://about.me/dzmitryh"><img src="https://avatars2.githubusercontent.com/u/5390492?v=4" width="100px;" alt=""/><br /><sub><b>Dima Gubin</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=dzmitryh" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/jjjimenez100"><img src="https://avatars3.githubusercontent.com/u/22243493?v=4" width="100px;" alt=""/><br /><sub><b>Joshua Jimenez</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=jjjimenez100" title="Code">💻</a></td>
+    <td align="center"><a href="http://about.me/kaiwinter"><img src="https://avatars0.githubusercontent.com/u/110982?v=4" width="100px;" alt=""/><br /><sub><b>Kai Winter</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=kaiwinter" title="Code">💻</a></td>
+  </tr>
+  <tr>
+    <td align="center"><a href="https://github.com/lbroman"><img src="https://avatars1.githubusercontent.com/u/86007?v=4" width="100px;" alt=""/><br /><sub><b>lbroman</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=lbroman" title="Code">💻</a></td>
+    <td align="center"><a href="https://przemeknowak.com"><img src="https://avatars1.githubusercontent.com/u/3254609?v=4" width="100px;" alt=""/><br /><sub><b>Przemek</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=pnowy" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/prafful1"><img src="https://avatars0.githubusercontent.com/u/14350274?v=4" width="100px;" alt=""/><br /><sub><b>Prafful Agarwal</b></sub></a><br /><a href="#content-prafful1" title="Content">🖋</a></td>
+    <td align="center"><a href="https://github.com/sankypanhale"><img src="https://avatars1.githubusercontent.com/u/6478783?v=4" width="100px;" alt=""/><br /><sub><b>Sanket Panhale</b></sub></a><br /><a href="#content-sankypanhale" title="Content">🖋</a></td>
+  </tr>
+  <tr>
+    <td align="center"><a href="https://github.com/staillebois"><img src="https://avatars0.githubusercontent.com/u/23701200?v=4" width="100px;" alt=""/><br /><sub><b>staillebois</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=staillebois" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/valdar-hu"><img src="https://avatars3.githubusercontent.com/u/17962817?v=4" width="100px;" alt=""/><br /><sub><b>Krisztián Nagy</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=valdar-hu" title="Code">💻</a></td>
+    <td align="center"><a href="https://www.vanogrid.com"><img src="https://avatars0.githubusercontent.com/u/4307918?v=4" width="100px;" alt=""/><br /><sub><b>Alexander Ivanov</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=vanogrid" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/yosfik"><img src="https://avatars3.githubusercontent.com/u/4850270?v=4" width="100px;" alt=""/><br /><sub><b>Yosfik Alqadri</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=yosfik" title="Code">💻</a></td>
+  </tr>
+  <tr>
+    <td align="center"><a href="https://github.com/7agustibm"><img src="https://avatars0.githubusercontent.com/u/8149332?v=4" width="100px;" alt=""/><br /><sub><b>Agustí Becerra Milà</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=7agustibm" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/Juaanma"><img src="https://avatars3.githubusercontent.com/u/7390500?v=4" width="100px;" alt=""/><br /><sub><b>Juan Manuel Suárez</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=Juaanma" title="Code">💻</a></td>
+    <td align="center"><a href="http://www.devsedge.net/"><img src="https://avatars0.githubusercontent.com/u/9956006?v=4" width="100px;" alt=""/><br /><sub><b>Luigi Cortese</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=LuigiCortese" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/Rzeposlaw"><img src="https://avatars2.githubusercontent.com/u/18425745?v=4" width="100px;" alt=""/><br /><sub><b>Katarzyna Rzepecka</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=Rzeposlaw" title="Code">💻</a></td>
+  </tr>
+  <tr>
+    <td align="center"><a href="http://adamski.pro"><img src="https://avatars1.githubusercontent.com/u/6537430?v=4" width="100px;" alt=""/><br /><sub><b>adamski.pro</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=akrystian" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/baislsl"><img src="https://avatars0.githubusercontent.com/u/17060584?v=4" width="100px;" alt=""/><br /><sub><b>Shengli Bai</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=baislsl" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/besok"><img src="https://avatars2.githubusercontent.com/u/29834592?v=4" width="100px;" alt=""/><br /><sub><b>Boris</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=besok" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/dmitraver"><img src="https://avatars3.githubusercontent.com/u/1798156?v=4" width="100px;" alt=""/><br /><sub><b>Dmitry Avershin</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=dmitraver" title="Code">💻</a></td>
+  </tr>
+  <tr>
+    <td align="center"><a href="https://github.com/fanofxiaofeng"><img src="https://avatars0.githubusercontent.com/u/3983683?v=4" width="100px;" alt=""/><br /><sub><b>靳阳</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=fanofxiaofeng" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/hoangnam2261"><img src="https://avatars2.githubusercontent.com/u/31692990?v=4" width="100px;" alt=""/><br /><sub><b>hoangnam2261</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=hoangnam2261" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/jarpit96"><img src="https://avatars2.githubusercontent.com/u/10098713?v=4" width="100px;" alt=""/><br /><sub><b>Arpit Jain</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=jarpit96" title="Code">💻</a></td>
+    <td align="center"><a href="http://joningi.net"><img src="https://avatars2.githubusercontent.com/u/6115148?v=4" width="100px;" alt=""/><br /><sub><b>Jón Ingi Sveinbjörnsson</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=joningiwork" title="Code">💻</a></td>
+  </tr>
+  <tr>
+    <td align="center"><a href="https://github.com/kirill-vlasov"><img src="https://avatars3.githubusercontent.com/u/16112495?v=4" width="100px;" alt=""/><br /><sub><b>Kirill Vlasov</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=kirill-vlasov" title="Code">💻</a></td>
+    <td align="center"><a href="http://mitchell-irvin.com"><img src="https://avatars0.githubusercontent.com/u/16233245?v=4" width="100px;" alt=""/><br /><sub><b>Mitchell Irvin</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=mitchellirvin" title="Code">💻</a></td>
+    <td align="center"><a href="https://ranjeet-floyd.github.io"><img src="https://avatars0.githubusercontent.com/u/1992972?v=4" width="100px;" alt=""/><br /><sub><b>Ranjeet</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=ranjeet-floyd" title="Code">💻</a></td>
+    <td align="center"><a href="https://alwayswithme.github.io"><img src="https://avatars3.githubusercontent.com/u/3234786?v=4" width="100px;" alt=""/><br /><sub><b>PhoenixYip</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=Alwayswithme" title="Code">💻</a></td>
+  </tr>
+  <tr>
+    <td align="center"><a href="https://github.com/MSaifAsif"><img src="https://avatars1.githubusercontent.com/u/6280554?v=4" width="100px;" alt=""/><br /><sub><b>M Saif Asif</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=MSaifAsif" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/kanwarpreet25"><img src="https://avatars0.githubusercontent.com/u/39183641?v=4" width="100px;" alt=""/><br /><sub><b>kanwarpreet25</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=kanwarpreet25" title="Code">💻</a></td>
+    <td align="center"><a href="http://leonmak.me"><img src="https://avatars3.githubusercontent.com/u/13071508?v=4" width="100px;" alt=""/><br /><sub><b>Leon Mak</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=leonmak" title="Code">💻</a></td>
+    <td align="center"><a href="http://www.wramdemark.se"><img src="https://avatars2.githubusercontent.com/u/7052193?v=4" width="100px;" alt=""/><br /><sub><b>Per Wramdemark</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=perwramdemark" title="Code">💻</a></td>
+  </tr>
+  <tr>
+    <td align="center"><a href="https://github.com/waisuan"><img src="https://avatars2.githubusercontent.com/u/10975700?v=4" width="100px;" alt=""/><br /><sub><b>Evan Sia Wai Suan</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=waisuan" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/AnaghaSasikumar"><img src="https://avatars2.githubusercontent.com/u/42939261?v=4" width="100px;" alt=""/><br /><sub><b>AnaghaSasikumar</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=AnaghaSasikumar" title="Code">💻</a></td>
+    <td align="center"><a href="https://christofferh.com"><img src="https://avatars1.githubusercontent.com/u/767643?v=4" width="100px;" alt=""/><br /><sub><b>Christoffer Hamberg</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=christofferh" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/dgruntz"><img src="https://avatars0.githubusercontent.com/u/1516800?v=4" width="100px;" alt=""/><br /><sub><b>Dominik Gruntz</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=dgruntz" title="Code">💻</a></td>
+  </tr>
+  <tr>
+    <td align="center"><a href="https://bitbucket.org/hannespernpeintner/"><img src="https://avatars3.githubusercontent.com/u/1679437?v=4" width="100px;" alt=""/><br /><sub><b>Hannes</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=hannespernpeintner" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/leogtzr"><img src="https://avatars0.githubusercontent.com/u/1211969?v=4" width="100px;" alt=""/><br /><sub><b>Leo Gutiérrez Ramírez</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=leogtzr" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/npczwh"><img src="https://avatars0.githubusercontent.com/u/14066422?v=4" width="100px;" alt=""/><br /><sub><b>Zhang WH</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=npczwh" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/oconnelc"><img src="https://avatars0.githubusercontent.com/u/1112973?v=4" width="100px;" alt=""/><br /><sub><b>Christopher O'Connell</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=oconnelc" title="Code">💻</a></td>
+  </tr>
+  <tr>
+    <td align="center"><a href="https://github.com/giorgosmav21"><img src="https://avatars2.githubusercontent.com/u/22855493?v=4" width="100px;" alt=""/><br /><sub><b>George Mavroeidis</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=giorgosmav21" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/hbothra15"><img src="https://avatars1.githubusercontent.com/u/7418012?v=4" width="100px;" alt=""/><br /><sub><b>Hemant Bothra</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=hbothra15" title="Code">💻</a></td>
+    <td align="center"><a href="https://www.kevinpeters.net/about/"><img src="https://avatars1.githubusercontent.com/u/12736734?v=4" width="100px;" alt=""/><br /><sub><b>Kevin Peters</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=igeligel" title="Code">💻</a></td>
+    <td align="center"><a href="https://llorllale.github.io/"><img src="https://avatars1.githubusercontent.com/u/2019896?v=4" width="100px;" alt=""/><br /><sub><b>George Aristy</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=llorllale" title="Code">💻</a></td>
+  </tr>
+  <tr>
+    <td align="center"><a href="https://github.com/mookkiah"><img src="https://avatars1.githubusercontent.com/u/8975264?v=4" width="100px;" alt=""/><br /><sub><b>Mahendran Mookkiah</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=mookkiah" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/Azureyjt"><img src="https://avatars2.githubusercontent.com/u/18476317?v=4" width="100px;" alt=""/><br /><sub><b>Azureyjt</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=Azureyjt" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/vehpsr"><img src="https://avatars2.githubusercontent.com/u/3133265?v=4" width="100px;" alt=""/><br /><sub><b>gans</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=vehpsr" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/ThatGuyWithTheHat"><img src="https://avatars0.githubusercontent.com/u/24470582?v=4" width="100px;" alt=""/><br /><sub><b>Matt</b></sub></a><br /><a href="#content-ThatGuyWithTheHat" title="Content">🖋</a></td>
+  </tr>
+  <tr>
+    <td align="center"><a href="https://www.linkedin.com/in/gopinathlangote/"><img src="https://avatars2.githubusercontent.com/u/10210778?v=4" width="100px;" alt=""/><br /><sub><b>Gopinath Langote</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=gopinath-langote" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/hoswey"><img src="https://avatars3.githubusercontent.com/u/3689445?v=4" width="100px;" alt=""/><br /><sub><b>Hoswey</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=hoswey" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/amit2103"><img src="https://avatars3.githubusercontent.com/u/7566692?v=4" width="100px;" alt=""/><br /><sub><b>Amit Pandey</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=amit2103" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/gwildor28"><img src="https://avatars0.githubusercontent.com/u/16000365?v=4" width="100px;" alt=""/><br /><sub><b>gwildor28</b></sub></a><br /><a href="#content-gwildor28" title="Content">🖋</a></td>
+  </tr>
+  <tr>
+    <td align="center"><a href="https://t.me/paul_docker"><img src="https://avatars1.githubusercontent.com/u/2404785?v=4" width="100px;" alt=""/><br /><sub><b>田浩</b></sub></a><br /><a href="#content-llitfkitfk" title="Content">🖋</a></td>
+    <td align="center"><a href="https://twitter.com/StPitsios"><img src="https://avatars1.githubusercontent.com/u/6773603?v=4" width="100px;" alt=""/><br /><sub><b>Stamatis Pitsios</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=pitsios-s" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/qza"><img src="https://avatars3.githubusercontent.com/u/233149?v=4" width="100px;" alt=""/><br /><sub><b>qza</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=qza" title="Code">💻</a></td>
+    <td align="center"><a href="http://tschis.github.io"><img src="https://avatars1.githubusercontent.com/u/20662669?v=4" width="100px;" alt=""/><br /><sub><b>Rodolfo Forte</b></sub></a><br /><a href="#content-Tschis" title="Content">🖋</a></td>
+  </tr>
+  <tr>
+    <td align="center"><a href="https://github.com/ankurkaushal"><img src="https://avatars2.githubusercontent.com/u/2236616?v=4" width="100px;" alt=""/><br /><sub><b>Ankur Kaushal</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=ankurkaushal" title="Code">💻</a></td>
+    <td align="center"><a href="https://www.linkedin.com/in/ovidijus-okinskas/"><img src="https://avatars0.githubusercontent.com/u/20372387?v=4" width="100px;" alt=""/><br /><sub><b>Ovidijus Okinskas</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=okinskas" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/robertt240"><img src="https://avatars1.githubusercontent.com/u/9137432?v=4" width="100px;" alt=""/><br /><sub><b>Robert Kasperczyk</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=robertt240" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/trautonen"><img src="https://avatars3.githubusercontent.com/u/1641063?v=4" width="100px;" alt=""/><br /><sub><b>Tapio Rautonen</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=trautonen" title="Code">💻</a></td>
+  </tr>
+  <tr>
+    <td align="center"><a href="http://vk.com/yuri.orlov"><img src="https://avatars0.githubusercontent.com/u/1595733?v=4" width="100px;" alt=""/><br /><sub><b>Yuri Orlov</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=yorlov" title="Code">💻</a></td>
+    <td align="center"><a href="https://www.linkedin.com/in/varunu28/"><img src="https://avatars0.githubusercontent.com/u/7676016?v=4" width="100px;" alt=""/><br /><sub><b>Varun Upadhyay</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=varunu28" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/PalAditya"><img src="https://avatars2.githubusercontent.com/u/25523604?v=4" width="100px;" alt=""/><br /><sub><b>Aditya Pal</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=PalAditya" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/grzesiekkedzior"><img src="https://avatars3.githubusercontent.com/u/23739158?v=4" width="100px;" alt=""/><br /><sub><b>grzesiekkedzior</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=grzesiekkedzior" title="Code">💻</a></td>
+  </tr>
+  <tr>
+    <td align="center"><a href="https://github.com/sivasubramanim"><img src="https://avatars2.githubusercontent.com/u/51107434?v=4" width="100px;" alt=""/><br /><sub><b>Sivasubramani M</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=sivasubramanim" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/d4gg4d"><img src="https://avatars2.githubusercontent.com/u/99457?v=4" width="100px;" alt=""/><br /><sub><b>Sami Airaksinen</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=d4gg4d" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/vertti"><img src="https://avatars0.githubusercontent.com/u/557751?v=4" width="100px;" alt=""/><br /><sub><b>Janne Sinivirta</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=vertti" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/Bobo1239"><img src="https://avatars1.githubusercontent.com/u/2302947?v=4" width="100px;" alt=""/><br /><sub><b>Boris-Chengbiao Zhou</b></sub></a><br /><a href="#content-Bobo1239" title="Content">🖋</a></td>
+  </tr>
+  <tr>
+    <td align="center"><a href="https://jahhein.github.io"><img src="https://avatars2.githubusercontent.com/u/10779515?v=4" width="100px;" alt=""/><br /><sub><b>Jacob Hein</b></sub></a><br /><a href="#content-Jahhein" title="Content">🖋</a></td>
+    <td align="center"><a href="https://github.com/iamrichardjones"><img src="https://avatars3.githubusercontent.com/u/14842151?v=4" width="100px;" alt=""/><br /><sub><b>Richard Jones</b></sub></a><br /><a href="#content-iamrichardjones" title="Content">🖋</a></td>
+    <td align="center"><a href="https://rachelcarmena.github.io"><img src="https://avatars0.githubusercontent.com/u/22792183?v=4" width="100px;" alt=""/><br /><sub><b>Rachel M. Carmena</b></sub></a><br /><a href="#content-rachelcarmena" title="Content">🖋</a></td>
+  </tr>
+</table>
+
+<!-- markdownlint-enable -->
+<!-- prettier-ignore-end -->
+<!-- ALL-CONTRIBUTORS-LIST:END -->

abstract-document/README.md

@@ -5,13 +5,13 @@ folder: abstract-document
 permalink: /patterns/abstract-document/
 categories: Structural
 tags: 
- - Java
- - Difficulty-Intermediate
+ - Extensibility
 ---
 
 ## Intent
 Achieve flexibility of untyped languages and keep the type-safety 
 
+## Class diagram
 ![alt text](./etc/abstract-document.png "Abstract Document Traits and Domain")
 
 
@@ -26,4 +26,4 @@ Use the Abstract Document Pattern when
 ## Credits
 
 * [Wikipedia: Abstract Document Pattern](https://en.wikipedia.org/wiki/Abstract_Document_Pattern)
-* [Martin Fowler: Dealing with properties](http://martinfowler.com/apsupp/properties.pdf)
+* [Martin Fowler: Dealing with properties](http://martinfowler.com/apsupp/properties.pdf)

abstract-document/etc/abstract-document.urm.puml

@@ -0,0 +1,65 @@
+@startuml
+package com.iluwatar.abstractdocument.domain.enums {
+  enum Property {
+    + MODEL {static}
+    + PARTS {static}
+    + PRICE {static}
+    + TYPE {static}
+    + valueOf(name : String) : Property {static}
+    + values() : Property[] {static}
+  }
+}
+package com.iluwatar.abstractdocument.domain {
+  class Car {
+    + Car(properties : Map<String, Object>)
+  }
+  interface HasModel {
+    + getModel() : Optional<String>
+  }
+  interface HasParts {
+    + getParts() : Stream<Part>
+  }
+  interface HasPrice {
+    + getPrice() : Optional<Number>
+  }
+  interface HasType {
+    + getType() : Optional<String>
+  }
+  class Part {
+    + Part(properties : Map<String, Object>)
+  }
+}
+package com.iluwatar.abstractdocument {
+  abstract class AbstractDocument {
+    - properties : Map<String, Object>
+    # AbstractDocument(properties : Map<String, Object>)
+    + children(key : String, constructor : Function<Map<String, Object>, T>) : Stream<T>
+    + get(key : String) : Object
+    + put(key : String, value : Object)
+    + toString() : String
+  }
+  class App {
+    - LOGGER : Logger {static}
+    + App()
+    + main(args : String[]) {static}
+  }
+  interface Document {
+    + children(String, Function<Map<String, Object>, T>) : Stream<T> {abstract}
+    + get(String) : Object {abstract}
+    + put(String, Object) {abstract}
+  }
+}
+AbstractDocument ..|> Document 
+Car ..|> HasModel 
+Car ..|> HasPrice 
+Car ..|> HasParts 
+Car --|> AbstractDocument 
+HasModel --|> Document 
+HasParts --|> Document 
+HasPrice --|> Document 
+HasType --|> Document 
+Part ..|> HasType 
+Part ..|> HasModel 
+Part ..|> HasPrice 
+Part --|> AbstractDocument 
+@enduml

abstract-document/pom.xml

@@ -1,47 +1,55 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<!--
-
-    The MIT License
-    Copyright (c) 2014-2016 Ilkka Seppälä
-
-    Permission is hereby granted, free of charge, to any person obtaining a copy
-    of this software and associated documentation files (the "Software"), to deal
-    in the Software without restriction, including without limitation the rights
-    to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-    copies of the Software, and to permit persons to whom the Software is
-    furnished to do so, subject to the following conditions:
-
-    The above copyright notice and this permission notice shall be included in
-    all copies or substantial portions of the Software.
-
-    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-    IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-    AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-    OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
-    THE SOFTWARE.
-
--->
-<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
-    <modelVersion>4.0.0</modelVersion>
-    <parent>
-        <artifactId>java-design-patterns</artifactId>
-        <groupId>com.iluwatar</groupId>
-        <version>1.21.0-SNAPSHOT</version>
-    </parent>
-    <artifactId>abstract-document</artifactId>
-    <dependencies>
-        <dependency>
-            <groupId>org.junit.jupiter</groupId>
-            <artifactId>junit-jupiter-api</artifactId>
-            <scope>test</scope>
-        </dependency>
-        <dependency>
-            <groupId>org.junit.jupiter</groupId>
-            <artifactId>junit-jupiter-engine</artifactId>
-            <scope>test</scope>
-        </dependency>
-    </dependencies>
-</project>
+<!-- The MIT License Copyright © 2014-2019 Ilkka Seppälä Permission is hereby 
+	granted, free of charge, to any person obtaining a copy of this software 
+	and associated documentation files (the "Software"), to deal in the Software 
+	without restriction, including without limitation the rights to use, copy, 
+	modify, merge, publish, distribute, sublicense, and/or sell copies of the 
+	Software, and to permit persons to whom the Software is furnished to do so, 
+	subject to the following conditions: The above copyright notice and this 
+	permission notice shall be included in all copies or substantial portions 
+	of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY 
+	KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 
+	MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN 
+	NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, 
+	DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, 
+	ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER 
+	DEALINGS IN THE SOFTWARE. -->
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+	<modelVersion>4.0.0</modelVersion>
+	<parent>
+		<artifactId>java-design-patterns</artifactId>
+		<groupId>com.iluwatar</groupId>
+		<version>1.23.0-SNAPSHOT</version>
+	</parent>
+	<artifactId>abstract-document</artifactId>
+	<dependencies>
+		<dependency>
+			<groupId>org.junit.jupiter</groupId>
+			<artifactId>junit-jupiter-engine</artifactId>
+			<scope>test</scope>
+		</dependency>
+	</dependencies>
+	<build>
+		<plugins>
+			<!-- Maven assembly plugin is invoked with default setting which we have 
+				in parent pom and specifying the class having main method -->
+			<plugin>
+				<groupId>org.apache.maven.plugins</groupId>
+				<artifactId>maven-assembly-plugin</artifactId>
+				<executions>
+					<execution>
+						<configuration>
+							<archive>
+								<manifest>
+									<mainClass>com.iluwatar.abstractdocument.App</mainClass>
+								</manifest>
+							</archive>
+						</configuration>
+					</execution>
+				</executions>
+			</plugin>
+		</plugins>
+	</build>
+</project>

abstract-document/src/main/java/com/iluwatar/abstractdocument/AbstractDocument.java

@@ -1,17 +1,17 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
- * <p>
+ * Copyright © 2014-2019 Ilkka Seppälä
+ *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
  * in the Software without restriction, including without limitation the rights
  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  * copies of the Software, and to permit persons to whom the Software is
  * furnished to do so, subject to the following conditions:
- * <p>
+ *
  * The above copyright notice and this permission notice shall be included in
  * all copies or substantial portions of the Software.
- * <p>
+ *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
@@ -20,17 +20,18 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.abstractdocument;
 
+import java.util.Collection;
 import java.util.List;
 import java.util.Map;
 import java.util.Objects;
-import java.util.Optional;
 import java.util.function.Function;
 import java.util.stream.Stream;
 
 /**
- * Abstract implementation of Document interface
+ * Abstract implementation of Document interface.
  */
 public abstract class AbstractDocument implements Document {
 
@@ -54,17 +55,21 @@ public abstract class AbstractDocument implements Document {
 
   @Override
   public <T> Stream<T> children(String key, Function<Map<String, Object>, T> constructor) {
-    Optional<List<Map<String, Object>>> any = Stream.of(get(key)).filter(el -> el != null)
-        .map(el -> (List<Map<String, Object>>) el).findAny();
-    return any.isPresent() ? any.get().stream().map(constructor) : Stream.empty();
+    return Stream.ofNullable(get(key))
+        .filter(Objects::nonNull)
+        .map(el -> (List<Map<String, Object>>) el)
+        .findAny()
+        .stream()
+        .flatMap(Collection::stream)
+        .map(constructor);
   }
 
   @Override
   public String toString() {
-    StringBuilder builder = new StringBuilder();
+    var builder = new StringBuilder();
     builder.append(getClass().getName()).append("[");
-    properties.entrySet()
-        .forEach(e -> builder.append("[").append(e.getKey()).append(" : ").append(e.getValue()).append("]"));
+    properties.forEach((key, value) -> builder.append("[").append(key).append(" : ").append(value)
+        .append("]"));
     builder.append("]");
     return builder.toString();
   }

abstract-document/src/main/java/com/iluwatar/abstractdocument/App.java

@@ -1,17 +1,17 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
- * <p>
+ * Copyright © 2014-2019 Ilkka Seppälä
+ *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
  * in the Software without restriction, including without limitation the rights
  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  * copies of the Software, and to permit persons to whom the Software is
  * furnished to do so, subject to the following conditions:
- * <p>
+ *
  * The above copyright notice and this permission notice shall be included in
  * all copies or substantial portions of the Software.
- * <p>
+ *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
@@ -20,67 +20,64 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.abstractdocument;
 
 import com.iluwatar.abstractdocument.domain.Car;
-import com.iluwatar.abstractdocument.domain.HasModel;
-import com.iluwatar.abstractdocument.domain.HasParts;
-import com.iluwatar.abstractdocument.domain.HasPrice;
-import com.iluwatar.abstractdocument.domain.HasType;
+import com.iluwatar.abstractdocument.domain.enums.Property;
+import java.util.List;
+import java.util.Map;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import java.util.Arrays;
-import java.util.HashMap;
-import java.util.Map;
-
 /**
- * The Abstract Document pattern enables handling additional, non-static
- * properties. This pattern uses concept of traits to enable type safety and
- * separate properties of different classes into set of interfaces.
- * <p>
- * <p>
- * In Abstract Document pattern,({@link AbstractDocument}) fully implements
- * {@link Document}) interface. Traits are then defined to enable access to
- * properties in usual, static way.
+ * The Abstract Document pattern enables handling additional, non-static properties. This pattern
+ * uses concept of traits to enable type safety and separate properties of different classes into
+ * set of interfaces.
+ *
+ * <p>In Abstract Document pattern,({@link AbstractDocument}) fully implements {@link Document})
+ * interface. Traits are then defined to enable access to properties in usual, static way.
  */
 public class App {
 
   private static final Logger LOGGER = LoggerFactory.getLogger(App.class);
 
   /**
-   * Executes the App
+   * Executes the App.
    */
   public App() {
     LOGGER.info("Constructing parts and car");
 
-    Map<String, Object> carProperties = new HashMap<>();
-    carProperties.put(HasModel.PROPERTY, "300SL");
-    carProperties.put(HasPrice.PROPERTY, 10000L);
+    var wheelProperties = Map.of(
+        Property.TYPE.toString(), "wheel",
+        Property.MODEL.toString(), "15C",
+        Property.PRICE.toString(), 100L);
 
-    Map<String, Object> wheelProperties = new HashMap<>();
-    wheelProperties.put(HasType.PROPERTY, "wheel");
-    wheelProperties.put(HasModel.PROPERTY, "15C");
-    wheelProperties.put(HasPrice.PROPERTY, 100L);
+    var doorProperties = Map.of(
+        Property.TYPE.toString(), "door",
+        Property.MODEL.toString(), "Lambo",
+        Property.PRICE.toString(), 300L);
 
-    Map<String, Object> doorProperties = new HashMap<>();
-    doorProperties.put(HasType.PROPERTY, "door");
-    doorProperties.put(HasModel.PROPERTY, "Lambo");
-    doorProperties.put(HasPrice.PROPERTY, 300L);
+    var carProperties = Map.of(
+        Property.MODEL.toString(), "300SL",
+        Property.PRICE.toString(), 10000L,
+        Property.PARTS.toString(), List.of(wheelProperties, doorProperties));
 
-    carProperties.put(HasParts.PROPERTY, Arrays.asList(wheelProperties, doorProperties));
-
-    Car car = new Car(carProperties);
+    var car = new Car(carProperties);
 
     LOGGER.info("Here is our car:");
-    LOGGER.info("-> model: {}", car.getModel().get());
-    LOGGER.info("-> price: {}", car.getPrice().get());
+    LOGGER.info("-> model: {}", car.getModel().orElseThrow());
+    LOGGER.info("-> price: {}", car.getPrice().orElseThrow());
     LOGGER.info("-> parts: ");
-    car.getParts().forEach(p -> LOGGER.info("\t{}/{}/{}", p.getType().get(), p.getModel().get(), p.getPrice().get()));
+    car.getParts().forEach(p -> LOGGER.info("\t{}/{}/{}",
+        p.getType().orElse(null),
+        p.getModel().orElse(null),
+        p.getPrice().orElse(null))
+    );
   }
 
   /**
-   * Program entry point
+   * Program entry point.
    *
    * @param args command line args
    */

abstract-document/src/main/java/com/iluwatar/abstractdocument/Document.java

@@ -1,17 +1,17 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
- * <p>
+ * Copyright © 2014-2019 Ilkka Seppälä
+ *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
  * in the Software without restriction, including without limitation the rights
  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  * copies of the Software, and to permit persons to whom the Software is
  * furnished to do so, subject to the following conditions:
- * <p>
+ *
  * The above copyright notice and this permission notice shall be included in
  * all copies or substantial portions of the Software.
- * <p>
+ *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
@@ -20,6 +20,7 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.abstractdocument;
 
 import java.util.Map;
@@ -27,12 +28,12 @@ import java.util.function.Function;
 import java.util.stream.Stream;
 
 /**
- * Document interface
+ * Document interface.
  */
 public interface Document {
 
   /**
-   * Puts the value related to the key
+   * Puts the value related to the key.
    *
    * @param key   element key
    * @param value element value
@@ -41,7 +42,7 @@ public interface Document {
   Void put(String key, Object value);
 
   /**
-   * Gets the value for the key
+   * Gets the value for the key.
    *
    * @param key element key
    * @return value or null
@@ -49,7 +50,7 @@ public interface Document {
   Object get(String key);
 
   /**
-   * Gets the stream of child documents
+   * Gets the stream of child documents.
    *
    * @param key         element key
    * @param constructor constructor of child class

abstract-document/src/main/java/com/iluwatar/abstractdocument/domain/Car.java

@@ -1,17 +1,17 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
- * <p>
+ * Copyright © 2014-2019 Ilkka Seppälä
+ *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
  * in the Software without restriction, including without limitation the rights
  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  * copies of the Software, and to permit persons to whom the Software is
  * furnished to do so, subject to the following conditions:
- * <p>
+ *
  * The above copyright notice and this permission notice shall be included in
  * all copies or substantial portions of the Software.
- * <p>
+ *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
@@ -20,14 +20,14 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.abstractdocument.domain;
 
+import com.iluwatar.abstractdocument.AbstractDocument;
 import java.util.Map;
 
-import com.iluwatar.abstractdocument.AbstractDocument;
-
 /**
- * Car entity
+ * Car entity.
  */
 public class Car extends AbstractDocument implements HasModel, HasPrice, HasParts {
 

abstract-document/src/main/java/com/iluwatar/abstractdocument/domain/HasModel.java

@@ -1,17 +1,17 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
- * <p>
+ * Copyright © 2014-2019 Ilkka Seppälä
+ *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
  * in the Software without restriction, including without limitation the rights
  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  * copies of the Software, and to permit persons to whom the Software is
  * furnished to do so, subject to the following conditions:
- * <p>
+ *
  * The above copyright notice and this permission notice shall be included in
  * all copies or substantial portions of the Software.
- * <p>
+ *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
@@ -20,21 +20,20 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.abstractdocument.domain;
 
+import com.iluwatar.abstractdocument.Document;
+import com.iluwatar.abstractdocument.domain.enums.Property;
 import java.util.Optional;
 
-import com.iluwatar.abstractdocument.Document;
-
 /**
- * HasModel trait for static access to 'model' property
+ * HasModel trait for static access to 'model' property.
  */
 public interface HasModel extends Document {
 
-  String PROPERTY = "model";
-
   default Optional<String> getModel() {
-    return Optional.ofNullable((String) get(PROPERTY));
+    return Optional.ofNullable((String) get(Property.MODEL.toString()));
   }
 
 }

abstract-document/src/main/java/com/iluwatar/abstractdocument/domain/HasParts.java

@@ -1,17 +1,17 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
- * <p>
+ * Copyright © 2014-2019 Ilkka Seppälä
+ *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
  * in the Software without restriction, including without limitation the rights
  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  * copies of the Software, and to permit persons to whom the Software is
  * furnished to do so, subject to the following conditions:
- * <p>
+ *
  * The above copyright notice and this permission notice shall be included in
  * all copies or substantial portions of the Software.
- * <p>
+ *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
@@ -20,21 +20,21 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.abstractdocument.domain;
 
+import com.iluwatar.abstractdocument.Document;
+import com.iluwatar.abstractdocument.domain.enums.Property;
 import java.util.stream.Stream;
 
-import com.iluwatar.abstractdocument.Document;
-
 /**
- * HasParts trait for static access to 'parts' property
+ * HasParts trait for static access to 'parts' property.
  */
 public interface HasParts extends Document {
 
-  String PROPERTY = "parts";
 
   default Stream<Part> getParts() {
-    return children(PROPERTY, Part::new);
+    return children(Property.PARTS.toString(), Part::new);
   }
 
 }

abstract-document/src/main/java/com/iluwatar/abstractdocument/domain/HasPrice.java

@@ -1,17 +1,17 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
- * <p>
+ * Copyright © 2014-2019 Ilkka Seppälä
+ *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
  * in the Software without restriction, including without limitation the rights
  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  * copies of the Software, and to permit persons to whom the Software is
  * furnished to do so, subject to the following conditions:
- * <p>
+ *
  * The above copyright notice and this permission notice shall be included in
  * all copies or substantial portions of the Software.
- * <p>
+ *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
@@ -20,21 +20,21 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.abstractdocument.domain;
 
+import com.iluwatar.abstractdocument.Document;
+import com.iluwatar.abstractdocument.domain.enums.Property;
 import java.util.Optional;
 
-import com.iluwatar.abstractdocument.Document;
-
 /**
- * HasPrice trait for static access to 'price' property
+ * HasPrice trait for static access to 'price' property.
  */
 public interface HasPrice extends Document {
 
-  String PROPERTY = "price";
 
   default Optional<Number> getPrice() {
-    return Optional.ofNullable((Number) get(PROPERTY));
+    return Optional.ofNullable((Number) get(Property.PRICE.toString()));
   }
 
 }

abstract-document/src/main/java/com/iluwatar/abstractdocument/domain/HasType.java

@@ -1,17 +1,17 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
- * <p>
+ * Copyright © 2014-2019 Ilkka Seppälä
+ *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
  * in the Software without restriction, including without limitation the rights
  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  * copies of the Software, and to permit persons to whom the Software is
  * furnished to do so, subject to the following conditions:
- * <p>
+ *
  * The above copyright notice and this permission notice shall be included in
  * all copies or substantial portions of the Software.
- * <p>
+ *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
@@ -20,21 +20,21 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.abstractdocument.domain;
 
 import com.iluwatar.abstractdocument.Document;
-
+import com.iluwatar.abstractdocument.domain.enums.Property;
 import java.util.Optional;
 
 /**
- * HasType trait for static access to 'type' property
+ * HasType trait for static access to 'type' property.
  */
 public interface HasType extends Document {
 
-  String PROPERTY = "type";
 
   default Optional<String> getType() {
-    return Optional.ofNullable((String) get(PROPERTY));
+    return Optional.ofNullable((String) get(Property.TYPE.toString()));
   }
 
 }

abstract-document/src/main/java/com/iluwatar/abstractdocument/domain/Part.java

@@ -1,17 +1,17 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
- * <p>
+ * Copyright © 2014-2019 Ilkka Seppälä
+ *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
  * in the Software without restriction, including without limitation the rights
  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  * copies of the Software, and to permit persons to whom the Software is
  * furnished to do so, subject to the following conditions:
- * <p>
+ *
  * The above copyright notice and this permission notice shall be included in
  * all copies or substantial portions of the Software.
- * <p>
+ *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
@@ -20,14 +20,14 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.abstractdocument.domain;
 
+import com.iluwatar.abstractdocument.AbstractDocument;
 import java.util.Map;
 
-import com.iluwatar.abstractdocument.AbstractDocument;
-
 /**
- * Part entity
+ * Part entity.
  */
 public class Part extends AbstractDocument implements HasType, HasModel, HasPrice {
 

abstract-document/src/main/java/com/iluwatar/abstractdocument/domain/enums/Property.java

@@ -0,0 +1,32 @@
+/*
+ * The MIT License
+ * Copyright © 2014-2019 Ilkka Seppälä
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+package com.iluwatar.abstractdocument.domain.enums;
+
+/**
+ * Enum To Describe Property type.
+ */
+public enum Property {
+
+  PARTS, TYPE, PRICE, MODEL
+}

abstract-document/src/main/java/com/iluwatar/abstractdocument/module-info.java

@@ -0,0 +1,26 @@
+/*
+ * The MIT License
+ * Copyright © 2014-2019 Ilkka Seppälä
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+module com.iluwatar.abstractdocument {
+	requires org.slf4j;
+}

abstract-document/src/test/java/com/iluwatar/abstractdocument/AbstractDocumentTest.java

@@ -1,17 +1,17 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
- * <p>
+ * Copyright © 2014-2019 Ilkka Seppälä
+ *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
  * in the Software without restriction, including without limitation the rights
  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  * copies of the Software, and to permit persons to whom the Software is
  * furnished to do so, subject to the following conditions:
- * <p>
+ *
  * The above copyright notice and this permission notice shall be included in
  * all copies or substantial portions of the Software.
- * <p>
+ *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
@@ -20,18 +20,17 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.abstractdocument;
 
-import org.junit.jupiter.api.Test;
-
-import java.util.Arrays;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
-import java.util.stream.Stream;
-
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import org.junit.jupiter.api.Test;
 
 /**
  * AbstractDocument test class
@@ -58,31 +57,28 @@ public class AbstractDocumentTest {
 
   @Test
   public void shouldRetrieveChildren() {
-    Map<String, Object> child1 = new HashMap<>();
-    Map<String, Object> child2 = new HashMap<>();
-    List<Map<String, Object>> children = Arrays.asList(child1, child2);
+    var children = List.of(Map.of(), Map.of());
 
     document.put(KEY, children);
 
-    Stream<DocumentImplementation> childrenStream = document.children(KEY, DocumentImplementation::new);
+    var childrenStream = document.children(KEY, DocumentImplementation::new);
     assertNotNull(children);
     assertEquals(2, childrenStream.count());
   }
 
   @Test
   public void shouldRetrieveEmptyStreamForNonExistingChildren() {
-    Stream<DocumentImplementation> children = document.children(KEY, DocumentImplementation::new);
+    var children = document.children(KEY, DocumentImplementation::new);
     assertNotNull(children);
     assertEquals(0, children.count());
   }
 
   @Test
   public void shouldIncludePropsInToString() {
-    Map<String, Object> props = new HashMap<>();
-    props.put(KEY, VALUE);
-    DocumentImplementation document = new DocumentImplementation(props);
-    assertNotNull(document.toString().contains(KEY));
-    assertNotNull(document.toString().contains(VALUE));
+    var props = Map.of(KEY, (Object) VALUE);
+    var document = new DocumentImplementation(props);
+    assertTrue(document.toString().contains(KEY));
+    assertTrue(document.toString().contains(VALUE));
   }
 
 }

abstract-document/src/test/java/com/iluwatar/abstractdocument/AppTest.java

@@ -1,17 +1,17 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
- * <p>
+ * Copyright © 2014-2019 Ilkka Seppälä
+ *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
  * in the Software without restriction, including without limitation the rights
  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  * copies of the Software, and to permit persons to whom the Software is
  * furnished to do so, subject to the following conditions:
- * <p>
+ *
  * The above copyright notice and this permission notice shall be included in
  * all copies or substantial portions of the Software.
- * <p>
+ *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
@@ -20,6 +20,7 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.abstractdocument;
 
 import org.junit.jupiter.api.Test;

abstract-document/src/test/java/com/iluwatar/abstractdocument/DomainTest.java

@@ -1,17 +1,17 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
- * <p>
+ * Copyright © 2014-2019 Ilkka Seppälä
+ *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
  * in the Software without restriction, including without limitation the rights
  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  * copies of the Software, and to permit persons to whom the Software is
  * furnished to do so, subject to the following conditions:
- * <p>
+ *
  * The above copyright notice and this permission notice shall be included in
  * all copies or substantial portions of the Software.
- * <p>
+ *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
@@ -20,22 +20,18 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.abstractdocument;
 
-import com.iluwatar.abstractdocument.domain.Car;
-import com.iluwatar.abstractdocument.domain.HasModel;
-import com.iluwatar.abstractdocument.domain.HasParts;
-import com.iluwatar.abstractdocument.domain.HasPrice;
-import com.iluwatar.abstractdocument.domain.HasType;
-import com.iluwatar.abstractdocument.domain.Part;
-import org.junit.jupiter.api.Test;
-
-import java.util.Arrays;
-import java.util.HashMap;
-import java.util.Map;
-
 import static org.junit.jupiter.api.Assertions.assertEquals;
 
+import com.iluwatar.abstractdocument.domain.Car;
+import com.iluwatar.abstractdocument.domain.Part;
+import com.iluwatar.abstractdocument.domain.enums.Property;
+import java.util.List;
+import java.util.Map;
+import org.junit.jupiter.api.Test;
+
 /**
  * Test for Part and Car
  */
@@ -50,27 +46,27 @@ public class DomainTest {
 
   @Test
   public void shouldConstructPart() {
-    Map<String, Object> partProperties = new HashMap<>();
-    partProperties.put(HasType.PROPERTY, TEST_PART_TYPE);
-    partProperties.put(HasModel.PROPERTY, TEST_PART_MODEL);
-    partProperties.put(HasPrice.PROPERTY, TEST_PART_PRICE);
-    Part part = new Part(partProperties);
-
-    assertEquals(TEST_PART_TYPE, part.getType().get());
-    assertEquals(TEST_PART_MODEL, part.getModel().get());
-    assertEquals(TEST_PART_PRICE, part.getPrice().get());
+    var partProperties = Map.of(
+        Property.TYPE.toString(), TEST_PART_TYPE,
+        Property.MODEL.toString(), TEST_PART_MODEL,
+        Property.PRICE.toString(), (Object) TEST_PART_PRICE
+    );
+    var part = new Part(partProperties);
+    assertEquals(TEST_PART_TYPE, part.getType().orElseThrow());
+    assertEquals(TEST_PART_MODEL, part.getModel().orElseThrow());
+    assertEquals(TEST_PART_PRICE, part.getPrice().orElseThrow());
   }
 
   @Test
   public void shouldConstructCar() {
-    Map<String, Object> carProperties = new HashMap<>();
-    carProperties.put(HasModel.PROPERTY, TEST_CAR_MODEL);
-    carProperties.put(HasPrice.PROPERTY, TEST_CAR_PRICE);
-    carProperties.put(HasParts.PROPERTY, Arrays.asList(new HashMap<>(), new HashMap<>()));
-    Car car = new Car(carProperties);
-
-    assertEquals(TEST_CAR_MODEL, car.getModel().get());
-    assertEquals(TEST_CAR_PRICE, car.getPrice().get());
+    var carProperties = Map.of(
+        Property.MODEL.toString(), TEST_CAR_MODEL,
+        Property.PRICE.toString(), TEST_CAR_PRICE,
+        Property.PARTS.toString(), List.of(Map.of(), Map.of())
+    );
+    var car = new Car(carProperties);
+    assertEquals(TEST_CAR_MODEL, car.getModel().orElseThrow());
+    assertEquals(TEST_CAR_PRICE, car.getPrice().orElseThrow());
     assertEquals(2, car.getParts().count());
   }
 

abstract-factory/README.md

@@ -5,9 +5,7 @@ folder: abstract-factory
 permalink: /patterns/abstract-factory/
 categories: Creational
 tags:
- - Java
- - Gang Of Four
- - Difficulty-Intermediate
+ - Gang of Four
 ---
 
 ## Also known as
@@ -109,10 +107,10 @@ public class OrcKingdomFactory implements KingdomFactory {
 Now we have our abstract factory that lets us make family of related objects i.e. Elven kingdom factory creates Elven castle, king and army etc.
 
 ```java
-KingdomFactory factory = new ElfKingdomFactory();
-Castle castle = factory.createCastle();
-King king = factory.createKing();
-Army army = factory.createArmy();
+var factory = new ElfKingdomFactory();
+var castle = factory.createCastle();
+var king = factory.createKing();
+var army = factory.createArmy();
 
 castle.getDescription();  // Output: This is the Elven castle!
 king.getDescription(); // Output: This is the Elven king!
@@ -143,7 +141,7 @@ public static class FactoryMaker {
 }
 
 public static void main(String[] args) {
-  App app = new App();
+  var app = new App();
 
   LOGGER.info("Elf Kingdom");
   app.createKingdom(FactoryMaker.makeFactory(KingdomType.ELF));
@@ -157,6 +155,9 @@ public static void main(String[] args) {
 }
 ```
 
+## Class diagram
+![alt text](./etc/abstract-factory.urm.png "Abstract Factory class diagram")
+
 
 ## Applicability
 Use the Abstract Factory pattern when
@@ -169,24 +170,25 @@ Use the Abstract Factory pattern when
 *	you need a run-time value to construct a particular dependency
 *	you want to decide which product to call from a family at runtime.
 *	you need to supply one or more parameters only known at run-time before you can resolve a dependency.
+* when you need consistency among products
+* you don’t want to change existing code when adding new products or families of products to the program.
 
 ## Use Cases:	
 
 *	Selecting to call the appropriate implementation of FileSystemAcmeService or DatabaseAcmeService or NetworkAcmeService at runtime.
 *	Unit test case writing becomes much easier
+* UI tools for different OS
 
 ## Consequences:
 
 *	Dependency injection in java hides the service class dependencies that can lead to runtime errors that would have been caught at compile time.
+* While the pattern is great when creating predefined objects, adding the new ones might be challenging.
+* The code may become more complicated than it should be, since a lot of new interfaces and classes are introduced along with the pattern.
 
 
 ## Tutorial
 * [Abstract Factory Pattern Tutorial](https://www.journaldev.com/1418/abstract-factory-design-pattern-in-java) 
 
-## Presentations
-
-* [Abstract Factory Pattern](etc/presentation.html) 
-
 
 ## Real world examples
 
@@ -196,4 +198,5 @@ Use the Abstract Factory pattern when
 
 ## Credits
 
-* [Design Patterns: Elements of Reusable Object-Oriented Software](http://www.amazon.com/Design-Patterns-Elements-Reusable-Object-Oriented/dp/0201633612)
+* [Design Patterns: Elements of Reusable Object-Oriented Software](https://www.amazon.com/gp/product/0201633612/ref=as_li_tl?ie=UTF8&camp=1789&creative=9325&creativeASIN=0201633612&linkCode=as2&tag=javadesignpat-20&linkId=675d49790ce11db99d90bde47f1aeb59)
+* [Head First Design Patterns: A Brain-Friendly Guide](https://www.amazon.com/gp/product/0596007124/ref=as_li_tl?ie=UTF8&camp=1789&creative=9325&creativeASIN=0596007124&linkCode=as2&tag=javadesignpat-20&linkId=6b8b6eea86021af6c8e3cd3fc382cb5b)

abstract-factory/etc/abstract-factory.urm.puml

@@ -0,0 +1,101 @@
+@startuml
+package com.iluwatar.abstractfactory {
+  class App {
+    - LOGGER : Logger {static}
+    - army : Army
+    - castle : Castle
+    - king : King
+    + App()
+    + createKingdom(factory : KingdomFactory)
+    + getArmy() : Army
+    ~ getArmy(factory : KingdomFactory) : Army
+    + getCastle() : Castle
+    ~ getCastle(factory : KingdomFactory) : Castle
+    + getKing() : King
+    ~ getKing(factory : KingdomFactory) : King
+    + main(args : String[]) {static}
+    - setArmy(army : Army)
+    - setCastle(castle : Castle)
+    - setKing(king : King)
+  }
+  class FactoryMaker {
+    + FactoryMaker()
+    + makeFactory(type : KingdomType) : KingdomFactory {static}
+  }
+  enum KingdomType {
+    + ELF {static}
+    + ORC {static}
+    + valueOf(name : String) : KingdomType {static}
+    + values() : KingdomType[] {static}
+  }
+  interface Army {
+    + getDescription() : String {abstract}
+  }
+  interface Castle {
+    + getDescription() : String {abstract}
+  }
+  class ElfArmy {
+    ~ DESCRIPTION : String {static}
+    + ElfArmy()
+    + getDescription() : String
+  }
+  class ElfCastle {
+    ~ DESCRIPTION : String {static}
+    + ElfCastle()
+    + getDescription() : String
+  }
+  class ElfKing {
+    ~ DESCRIPTION : String {static}
+    + ElfKing()
+    + getDescription() : String
+  }
+  class ElfKingdomFactory {
+    + ElfKingdomFactory()
+    + createArmy() : Army
+    + createCastle() : Castle
+    + createKing() : King
+  }
+  interface King {
+    + getDescription() : String {abstract}
+  }
+  interface KingdomFactory {
+    + createArmy() : Army {abstract}
+    + createCastle() : Castle {abstract}
+    + createKing() : King {abstract}
+  }
+  class OrcArmy {
+    ~ DESCRIPTION : String {static}
+    + OrcArmy()
+    + getDescription() : String
+  }
+  class OrcCastle {
+    ~ DESCRIPTION : String {static}
+    + OrcCastle()
+    + getDescription() : String
+  }
+  class OrcKing {
+    ~ DESCRIPTION : String {static}
+    + OrcKing()
+    + getDescription() : String
+  }
+  class OrcKingdomFactory {
+    + OrcKingdomFactory()
+    + createArmy() : Army
+    + createCastle() : Castle
+    + createKing() : King
+  }
+}
+KingdomType ..+ FactoryMaker
+App -->  "-castle" Castle
+FactoryMaker ..+ App
+App -->  "-king" King
+App -->  "-army" Army
+ElfArmy ..|> Army 
+ElfCastle ..|> Castle 
+ElfKing ..|> King 
+ElfKingdomFactory ..|> KingdomFactory 
+OrcArmy ..|> Army 
+OrcCastle ..|> Castle 
+OrcKing ..|> King 
+OrcKingdomFactory ..|> KingdomFactory 
+@enduml

abstract-factory/etc/presentation.html

@@ -1,190 +0,0 @@
-<!--
-
-    The MIT License
-    Copyright (c) 2017 Rodolfo Forte
-
-    Permission is hereby granted, free of charge, to any person obtaining a copy
-    of this software and associated documentation files (the "Software"), to deal
-    in the Software without restriction, including without limitation the rights
-    to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-    copies of the Software, and to permit persons to whom the Software is
-    furnished to do so, subject to the following conditions:
-
-    The above copyright notice and this permission notice shall be included in
-    all copies or substantial portions of the Software.
-
-    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-    IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-    AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-    OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
-    THE SOFTWARE.
-
--->
-<!DOCTYPE html>
-<html>
-  <head>
-    <title>Design Patterns - Abstract Factory Presentation</title>
-    <meta charset="utf-8">
-    <style>
-      @import url(https://fonts.googleapis.com/css?family=Yanone+Kaffeesatz);
-      @import url(https://fonts.googleapis.com/css?family=Droid+Serif:400,700,400italic);
-      @import url(https://fonts.googleapis.com/css?family=Ubuntu+Mono:400,700,400italic);
-
-      body { font-family: 'Droid Serif'; }
-      h1, h2, h3 {
-        font-family: 'Yanone Kaffeesatz';
-        font-weight: normal;
-      }
-      .remark-code, .remark-inline-code { font-family: 'Ubuntu Mono'; }
-	  
-	  blockquote {
-		border-left: 0.3em solid rgba(0,0,0,0.5);
-		padding: 0 15px;
-		font-style: italic;
-	  }
-	  
-	  img {
-		max-width:100%;
-	  }
-    </style>
-  </head>
-  <body>
-    <textarea id="source">
-
-class: center, middle
-
-# Abstract Factory
-
----
-
-# Also known as
-
-* Kit
-
----
-
-# Intent
-
-* Provide an interface for creating families of related or dependent objects without specifying their concrete classes
-
----
-
-# Explanation
-
-* [Wikipedia](https://en.wikipedia.org/wiki/Abstract_factory_pattern) says:
-  > "The abstract factory pattern provides a way to encapsulate a group of individual factories that have a common theme without specifying their concrete classes"
-
-<br />
-
-* In plain words:
-  * A factory that groups individual but related/dependent factories together without specifying their concrete classes;
-  * A factory of factories; 
-
----
-
-# Example
-
-* In a factory that creates kingdoms, we need objects with common theme:
-
-  * Elven kingdom needs an Elven king, Elven castle and Elven army;
-  
-  * Orcish kingdom needs an Orcish king, Orcish castle and Orcish army;
-
-<br />
-  
-* There is a dependency between the objects in the kingdom;
-
----
-
-# Diagram
-
-* Based on the kingdom example, the diagram below showcases the different concrete factories and their concrete products:
-
-.center[![Diagram](diagram1.png)]
-
-
----
-
-# Diagram
-
-* The class diagram below showcases the factory of factories;
-
-* At runtime, we can define which Kingdom type is needed and pass it as a parameter to define which concrete KingdomFactory to instantiate;
-
-* The concrete factory returned will then be able to produce the related objects of the specified type;
-  
-.center[![Diagram](diagram2.png)]
-
----
-
-# Applicability
-
-Use the Abstract Factory pattern when:
-
-* A system should be independent of how its products are created, composed and represented;
-
-* A system should be configured with one of multiple families of products;
-
-* A family of related product objects is designed to be used together, and you need to enforce this constraint;
-
-* You want to provide a class library of products, and you want to reveal just their interfaces, not their implementations;
-
----
-
-# Applicability
-
-Use the Abstract Factory pattern when:
-
-* The lifetime of the dependency is conceptually shorter than the lifetime of the consumer;
-
-* You need a run-time value to construct a particular dependency;
-
-* You want to decide which product to call from a family at runtime;
-
-* You need to supply one or more parameters only known at run-time before you can resolve a dependency;
-
----
-
-#Use Cases
-
-* Selecting to call the appropriate implementation of FileSystemAcmeService or DatabaseAcmeService or NetworkAcmeService at runtime;
-* Unit test case writing becomes much easier;
-
----
-
-# Consequences
-
-* Dependency injection in java hides the service class dependencies that can lead to runtime errors that would have been caught at compile time
-
----
-
-# Real world examples
-
-[javax.xml.parsers.DocumentBuilderFactory](http://docs.oracle.com/javase/8/docs/api/javax/xml/parsers/DocumentBuilderFactory.html)
-
-[javax.xml.transform.TransformerFactory](http://docs.oracle.com/javase/8/docs/api/javax/xml/transform/TransformerFactory.html#newInstance--)
-
-[javax.xml.xpath.XPathFactory](http://docs.oracle.com/javase/8/docs/api/javax/xml/xpath/XPathFactory.html#newInstance--)
-
----
-
-# Credits
-
-* [Design Patterns: Elements of Reusable Object-Oriented Software](http://www.amazon.com/Design-Patterns-Elements-Reusable-Object-Oriented/dp/0201633612)
-
----
-
-# Tutorials
-
-* Source code http://java-design-patterns.com/patterns/abstract-factory/
-
-    </textarea>
-    <script src="https://gnab.github.io/remark/downloads/remark-latest.min.js">
-    </script>
-    <script>
-      var slideshow = remark.create();
-    </script>
-  </body>
-</html>

abstract-factory/pom.xml

@@ -1,47 +1,56 @@
 <?xml version="1.0"?>
-<!--
-
-    The MIT License
-    Copyright (c) 2014-2016 Ilkka Seppälä
-
-    Permission is hereby granted, free of charge, to any person obtaining a copy
-    of this software and associated documentation files (the "Software"), to deal
-    in the Software without restriction, including without limitation the rights
-    to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-    copies of the Software, and to permit persons to whom the Software is
-    furnished to do so, subject to the following conditions:
-
-    The above copyright notice and this permission notice shall be included in
-    all copies or substantial portions of the Software.
-
-    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-    IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-    AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-    OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
-    THE SOFTWARE.
-
--->
-<project xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd" xmlns="http://maven.apache.org/POM/4.0.0"
-    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
-  <modelVersion>4.0.0</modelVersion>
-  <parent>
-    <groupId>com.iluwatar</groupId>
-    <artifactId>java-design-patterns</artifactId>
-    <version>1.21.0-SNAPSHOT</version>
-  </parent>
-  <artifactId>abstract-factory</artifactId>
-  <dependencies>
-    <dependency>
-      <groupId>org.junit.jupiter</groupId>
-      <artifactId>junit-jupiter-api</artifactId>
-      <scope>test</scope>
-    </dependency>
-    <dependency>
-      <groupId>org.junit.jupiter</groupId>
-      <artifactId>junit-jupiter-engine</artifactId>
-      <scope>test</scope>
-    </dependency>
-  </dependencies>
+<!-- The MIT License Copyright © 2014-2019 Ilkka Seppälä Permission is hereby 
+	granted, free of charge, to any person obtaining a copy of this software 
+	and associated documentation files (the "Software"), to deal in the Software 
+	without restriction, including without limitation the rights to use, copy, 
+	modify, merge, publish, distribute, sublicense, and/or sell copies of the 
+	Software, and to permit persons to whom the Software is furnished to do so, 
+	subject to the following conditions: The above copyright notice and this 
+	permission notice shall be included in all copies or substantial portions 
+	of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY 
+	KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 
+	MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN 
+	NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, 
+	DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, 
+	ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER 
+	DEALINGS IN THE SOFTWARE. -->
+<project
+	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"
+	xmlns="http://maven.apache.org/POM/4.0.0"
+	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
+	<modelVersion>4.0.0</modelVersion>
+	<parent>
+		<groupId>com.iluwatar</groupId>
+		<artifactId>java-design-patterns</artifactId>
+		<version>1.23.0-SNAPSHOT</version>
+	</parent>
+	<artifactId>abstract-factory</artifactId>
+	<dependencies>
+		<dependency>
+			<groupId>org.junit.jupiter</groupId>
+			<artifactId>junit-jupiter-engine</artifactId>
+			<scope>test</scope>
+		</dependency>
+	</dependencies>
+	<build>
+		<plugins>
+			<!-- Maven assembly plugin is invoked with default setting which we have 
+				in parent pom and specifying the class having main method -->
+			<plugin>
+				<groupId>org.apache.maven.plugins</groupId>
+				<artifactId>maven-assembly-plugin</artifactId>
+				<executions>
+					<execution>
+						<configuration>
+							<archive>
+								<manifest>
+									<mainClass>com.iluwatar.abstractfactory.App</mainClass>
+								</manifest>
+							</archive>
+						</configuration>
+					</execution>
+				</executions>
+			</plugin>
+		</plugins>
+	</build>
 </project>

abstract-factory/src/main/java/com/iluwatar/abstractfactory/App.java

@@ -1,6 +1,6 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
+ * Copyright © 2014-2019 Ilkka Seppälä
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -20,27 +20,26 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.abstractfactory;
 
+import com.iluwatar.abstractfactory.App.FactoryMaker.KingdomType;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import com.iluwatar.abstractfactory.App.FactoryMaker.KingdomType;
-
 /**
- * 
- * The Abstract Factory pattern provides a way to encapsulate a group of individual factories that have a common theme
- * without specifying their concrete classes. In normal usage, the client software creates a concrete implementation of
- * the abstract factory and then uses the generic interface of the factory to create the concrete objects that are part
- * of the theme. The client does not know (or care) which concrete objects it gets from each of these internal
- * factories, since it uses only the generic interfaces of their products. This pattern separates the details of
- * implementation of a set of objects from their general usage and relies on object composition, as object creation is
- * implemented in methods exposed in the factory interface.
- * <p>
- * The essence of the Abstract Factory pattern is a factory interface ({@link KingdomFactory}) and its implementations (
- * {@link ElfKingdomFactory}, {@link OrcKingdomFactory}). The example uses both concrete implementations to create a
- * king, a castle and an army.
- * 
+ * The Abstract Factory pattern provides a way to encapsulate a group of individual factories that
+ * have a common theme without specifying their concrete classes. In normal usage, the client
+ * software creates a concrete implementation of the abstract factory and then uses the generic
+ * interface of the factory to create the concrete objects that are part of the theme. The client
+ * does not know (or care) which concrete objects it gets from each of these internal factories,
+ * since it uses only the generic interfaces of their products. This pattern separates the details
+ * of implementation of a set of objects from their general usage and relies on object composition,
+ * as object creation is implemented in methods exposed in the factory interface.
+ *
+ * <p>The essence of the Abstract Factory pattern is a factory interface ({@link KingdomFactory})
+ * and its implementations ( {@link ElfKingdomFactory}, {@link OrcKingdomFactory}). The example uses
+ * both concrete implementations to create a king, a castle and an army.
  */
 public class App {
 
@@ -51,14 +50,14 @@ public class App {
   private Army army;
 
   /**
-   * Creates kingdom
+   * Creates kingdom.
    */
   public void createKingdom(final KingdomFactory factory) {
     setKing(factory.createKing());
     setCastle(factory.createCastle());
     setArmy(factory.createArmy());
   }
-  
+
   King getKing(final KingdomFactory factory) {
     return factory.createKing();
   }
@@ -70,7 +69,7 @@ public class App {
   private void setKing(final King king) {
     this.king = king;
   }
-  
+
   Castle getCastle(final KingdomFactory factory) {
     return factory.createCastle();
   }
@@ -82,7 +81,7 @@ public class App {
   private void setCastle(final Castle castle) {
     this.castle = castle;
   }
-  
+
   Army getArmy(final KingdomFactory factory) {
     return factory.createArmy();
   }
@@ -124,13 +123,12 @@ public class App {
 
   /**
    * Program entry point.
-   * 
-   * @param args
-   *          command line args
+   *
+   * @param args command line args
    */
   public static void main(String[] args) {
 
-    App app = new App();
+    var app = new App();
 
     LOGGER.info("Elf Kingdom");
     app.createKingdom(FactoryMaker.makeFactory(KingdomType.ELF));

abstract-factory/src/main/java/com/iluwatar/abstractfactory/Army.java

@@ -1,6 +1,6 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
+ * Copyright © 2014-2019 Ilkka Seppälä
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -20,12 +20,11 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.abstractfactory;
 
 /**
- * 
- * Army interface
- *
+ * Army interface.
  */
 public interface Army {
 

abstract-factory/src/main/java/com/iluwatar/abstractfactory/Castle.java

@@ -1,6 +1,6 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
+ * Copyright © 2014-2019 Ilkka Seppälä
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -20,12 +20,11 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.abstractfactory;
 
 /**
- * 
- * Castle interface
- *
+ * Castle interface.
  */
 public interface Castle {
 

abstract-factory/src/main/java/com/iluwatar/abstractfactory/ElfArmy.java

@@ -1,6 +1,6 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
+ * Copyright © 2014-2019 Ilkka Seppälä
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -20,12 +20,11 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.abstractfactory;
 
 /**
- * 
- * ElfArmy
- *
+ * ElfArmy.
  */
 public class ElfArmy implements Army {
 

abstract-factory/src/main/java/com/iluwatar/abstractfactory/ElfCastle.java

@@ -1,6 +1,6 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
+ * Copyright © 2014-2019 Ilkka Seppälä
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -20,12 +20,11 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.abstractfactory;
 
 /**
- * 
- * ElfCastle
- *
+ * ElfCastle.
  */
 public class ElfCastle implements Castle {
 

abstract-factory/src/main/java/com/iluwatar/abstractfactory/ElfKing.java

@@ -1,6 +1,6 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
+ * Copyright © 2014-2019 Ilkka Seppälä
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -20,12 +20,11 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.abstractfactory;
 
 /**
- * 
- * ElfKing
- *
+ * ElfKing.
  */
 public class ElfKing implements King {
 

abstract-factory/src/main/java/com/iluwatar/abstractfactory/ElfKingdomFactory.java

@@ -1,6 +1,6 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
+ * Copyright © 2014-2019 Ilkka Seppälä
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -20,23 +20,25 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.abstractfactory;
 
 /**
- * 
  * ElfKingdomFactory concrete factory.
- * 
  */
 public class ElfKingdomFactory implements KingdomFactory {
 
+  @Override
   public Castle createCastle() {
     return new ElfCastle();
   }
 
+  @Override
   public King createKing() {
     return new ElfKing();
   }
 
+  @Override
   public Army createArmy() {
     return new ElfArmy();
   }

abstract-factory/src/main/java/com/iluwatar/abstractfactory/King.java

@@ -1,6 +1,6 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
+ * Copyright © 2014-2019 Ilkka Seppälä
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -20,12 +20,11 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.abstractfactory;
 
 /**
- * 
- * King interface
- *
+ * King interface.
  */
 public interface King {
 

abstract-factory/src/main/java/com/iluwatar/abstractfactory/KingdomFactory.java

@@ -1,6 +1,6 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
+ * Copyright © 2014-2019 Ilkka Seppälä
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -20,12 +20,11 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.abstractfactory;
 
 /**
- * 
  * KingdomFactory factory interface.
- * 
  */
 public interface KingdomFactory {
 

abstract-factory/src/main/java/com/iluwatar/abstractfactory/OrcArmy.java

@@ -1,6 +1,6 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
+ * Copyright © 2014-2019 Ilkka Seppälä
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -20,12 +20,11 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.abstractfactory;
 
 /**
- * 
- * OrcArmy
- *
+ * OrcArmy.
  */
 public class OrcArmy implements Army {
 

abstract-factory/src/main/java/com/iluwatar/abstractfactory/OrcCastle.java

@@ -1,6 +1,6 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
+ * Copyright © 2014-2019 Ilkka Seppälä
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -20,12 +20,11 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.abstractfactory;
 
 /**
- * 
- * OrcCastle
- *
+ * OrcCastle.
  */
 public class OrcCastle implements Castle {
 

abstract-factory/src/main/java/com/iluwatar/abstractfactory/OrcKing.java

@@ -1,6 +1,6 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
+ * Copyright © 2014-2019 Ilkka Seppälä
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -20,12 +20,11 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.abstractfactory;
 
 /**
- * 
- * OrcKing
- *
+ * OrcKing.
  */
 public class OrcKing implements King {
 

abstract-factory/src/main/java/com/iluwatar/abstractfactory/OrcKingdomFactory.java

@@ -1,6 +1,6 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
+ * Copyright © 2014-2019 Ilkka Seppälä
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -20,23 +20,25 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.abstractfactory;
 
 /**
- * 
  * OrcKingdomFactory concrete factory.
- * 
  */
 public class OrcKingdomFactory implements KingdomFactory {
 
+  @Override
   public Castle createCastle() {
     return new OrcCastle();
   }
 
+  @Override
   public King createKing() {
     return new OrcKing();
   }
 
+  @Override
   public Army createArmy() {
     return new OrcArmy();
   }

abstract-factory/src/main/java/com/iluwatar/abstractfactory/module-info.java

@@ -0,0 +1,26 @@
+/*
+ * The MIT License
+ * Copyright © 2014-2019 Ilkka Seppälä
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+module com.iluwatar.abstractfactory {
+	requires org.slf4j;
+}

abstract-factory/src/test/java/com/iluwatar/abstractfactory/AbstractFactoryTest.java

@@ -1,6 +1,6 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
+ * Copyright © 2014-2019 Ilkka Seppälä
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -20,6 +20,7 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.abstractfactory;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
@@ -27,12 +28,11 @@ import static org.junit.jupiter.api.Assertions.assertTrue;
 
 import com.iluwatar.abstractfactory.App.FactoryMaker;
 import com.iluwatar.abstractfactory.App.FactoryMaker.KingdomType;
-
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 
 /**
- * Test for abstract factory
+ * Test for abstract factory.
  */
 public class AbstractFactoryTest {
 
@@ -48,30 +48,30 @@ public class AbstractFactoryTest {
 
   @Test
   public void king() {
-    final King elfKing = app.getKing(elfFactory);
+    final var elfKing = app.getKing(elfFactory);
     assertTrue(elfKing instanceof ElfKing);
     assertEquals(ElfKing.DESCRIPTION, elfKing.getDescription());
-    final King orcKing = app.getKing(orcFactory);
+    final var orcKing = app.getKing(orcFactory);
     assertTrue(orcKing instanceof OrcKing);
     assertEquals(OrcKing.DESCRIPTION, orcKing.getDescription());
   }
 
   @Test
   public void castle() {
-    final Castle elfCastle = app.getCastle(elfFactory);
+    final var elfCastle = app.getCastle(elfFactory);
     assertTrue(elfCastle instanceof ElfCastle);
     assertEquals(ElfCastle.DESCRIPTION, elfCastle.getDescription());
-    final Castle orcCastle = app.getCastle(orcFactory);
+    final var orcCastle = app.getCastle(orcFactory);
     assertTrue(orcCastle instanceof OrcCastle);
     assertEquals(OrcCastle.DESCRIPTION, orcCastle.getDescription());
   }
 
   @Test
   public void army() {
-    final Army elfArmy = app.getArmy(elfFactory);
+    final var elfArmy = app.getArmy(elfFactory);
     assertTrue(elfArmy instanceof ElfArmy);
     assertEquals(ElfArmy.DESCRIPTION, elfArmy.getDescription());
-    final Army orcArmy = app.getArmy(orcFactory);
+    final var orcArmy = app.getArmy(orcFactory);
     assertTrue(orcArmy instanceof OrcArmy);
     assertEquals(OrcArmy.DESCRIPTION, orcArmy.getDescription());
   }
@@ -79,9 +79,9 @@ public class AbstractFactoryTest {
   @Test
   public void createElfKingdom() {
     app.createKingdom(elfFactory);
-    final King king = app.getKing();
-    final Castle castle = app.getCastle();
-    final Army army = app.getArmy();
+    final var king = app.getKing();
+    final var castle = app.getCastle();
+    final var army = app.getArmy();
     assertTrue(king instanceof ElfKing);
     assertEquals(ElfKing.DESCRIPTION, king.getDescription());
     assertTrue(castle instanceof ElfCastle);
@@ -93,9 +93,9 @@ public class AbstractFactoryTest {
   @Test
   public void createOrcKingdom() {
     app.createKingdom(orcFactory);
-    final King king = app.getKing();
-    final Castle castle = app.getCastle();
-    final Army army = app.getArmy();
+    final var king = app.getKing();
+    final var castle = app.getCastle();
+    final var army = app.getArmy();
     assertTrue(king instanceof OrcKing);
     assertEquals(OrcKing.DESCRIPTION, king.getDescription());
     assertTrue(castle instanceof OrcCastle);

abstract-factory/src/test/java/com/iluwatar/abstractfactory/AppTest.java

@@ -1,6 +1,6 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
+ * Copyright © 2014-2019 Ilkka Seppälä
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -20,19 +20,17 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.abstractfactory;
 
 import org.junit.jupiter.api.Test;
 
-import java.io.IOException;
-
 /**
  * Tests that Abstract Factory example runs without errors.
  */
 public class AppTest {
   @Test
-  public void test() throws IOException {
-    String[] args = {};
-    App.main(args);
+  public void test() {
+    App.main(new String[]{});
   }
 }

acyclic-visitor/README.md

@@ -5,17 +5,18 @@ folder: acyclic-visitor
 permalink: /patterns/acyclic-visitor/
 categories: Behavioral
 tags:
- - Java
- - Difficulty-Intermediate
+ - Extensibility
 ---
 
-![alt text](./etc/acyclic-visitor.png "Acyclic Visitor")
-
 ## Intent
 Allow new functions to be added to existing class hierarchies without affecting those hierarchies, and without creating the troublesome dependency cycles that are inherent to the GOF VISITOR Pattern.
 
+## Class diagram
+![alt text](./etc/acyclic-visitor.png "Acyclic Visitor")
+
 ## Applicability
 This pattern can be used:
+
 * When you need to add a new function to an existing hierarchy without the need to alter or affect that hierarchy.
 * When there are functions that operate upon a hierarchy, but which do not belong in the hierarchy itself. e.g. the ConfigureForDOS / ConfigureForUnix / ConfigureForX issue.
 * When you need to perform very different operations on an object depending upon its type.
@@ -24,16 +25,18 @@ This pattern can be used:
 
 ## Consequences
 The good:
+
 * No dependency cycles between class hierarchies.
 * No need to recompile all the visitors if a new one is added.
 * Does not cause compilation failure in existing visitors if class hierarchy has a new member.
 
 The bad:
+
 * Violates the principle of least surprise or Liskov's Substitution principle by showing that it can accept all visitors but actually only being interested in particular visitors.
 * Parallel hierarchy of visitors has to be created for all members in visitable class hierarchy.
 
 ## Related patterns
-* [Visitor Pattern](../visitor/README.md)
+* [Visitor Pattern](../visitor/)
 
 ## Credits
-* [Acyclic Visitor](http://condor.depaul.edu/dmumaugh/OOT/Design-Principles/acv.pdf)
+* [Acyclic Visitor](http://condor.depaul.edu/dmumaugh/OOT/Design-Principles/acv.pdf)

acyclic-visitor/etc/acyclic-visitor.urm.puml

@@ -0,0 +1,53 @@
+@startuml
+package com.iluwatar.acyclicvisitor {
+  interface AllModemVisitor {
+  }
+  class App {
+    + App()
+    + main(args : String[]) {static}
+  }
+  class ConfigureForDosVisitor {
+    - LOGGER : Logger {static}
+    + ConfigureForDosVisitor()
+    + visit(hayes : Hayes)
+    + visit(zoom : Zoom)
+  }
+  class ConfigureForUnixVisitor {
+    - LOGGER : Logger {static}
+    + ConfigureForUnixVisitor()
+    + visit(zoom : Zoom)
+  }
+  class Hayes {
+    - LOGGER : Logger {static}
+    + Hayes()
+    + accept(modemVisitor : ModemVisitor)
+    + toString() : String
+  }
+  interface HayesVisitor {
+    + visit(Hayes) {abstract}
+  }
+  abstract class Modem {
+    + Modem()
+    + accept(ModemVisitor) {abstract}
+  }
+  interface ModemVisitor {
+  }
+  class Zoom {
+    - LOGGER : Logger {static}
+    + Zoom()
+    + accept(modemVisitor : ModemVisitor)
+    + toString() : String
+  }
+  interface ZoomVisitor {
+    + visit(Zoom) {abstract}
+  }
+}
+AllModemVisitor --|> ZoomVisitor 
+AllModemVisitor --|> HayesVisitor 
+ConfigureForDosVisitor ..|> AllModemVisitor 
+ConfigureForUnixVisitor ..|> ZoomVisitor 
+Hayes --|> Modem 
+HayesVisitor --|> ModemVisitor 
+Zoom --|> Modem 
+ZoomVisitor --|> ModemVisitor 
+@enduml

acyclic-visitor/pom.xml

@@ -1,38 +1,29 @@
-<!--
-
-    The MIT License
-    Copyright (c) 2014 Ilkka Seppälä
-
-    Permission is hereby granted, free of charge, to any person obtaining a copy
-    of this software and associated documentation files (the "Software"), to deal
-    in the Software without restriction, including without limitation the rights
-    to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-    copies of the Software, and to permit persons to whom the Software is
-    furnished to do so, subject to the following conditions:
-
-    The above copyright notice and this permission notice shall be included in
-    all copies or substantial portions of the Software.
-
-    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-    IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-    AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-    OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
-    THE SOFTWARE.
-
--->
+<!-- The MIT License Copyright © 2014-2019 Ilkka Seppälä Permission is hereby 
+	granted, free of charge, to any person obtaining a copy of this software 
+	and associated documentation files (the "Software"), to deal in the Software 
+	without restriction, including without limitation the rights to use, copy, 
+	modify, merge, publish, distribute, sublicense, and/or sell copies of the 
+	Software, and to permit persons to whom the Software is furnished to do so, 
+	subject to the following conditions: The above copyright notice and this 
+	permission notice shall be included in all copies or substantial portions 
+	of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY 
+	KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 
+	MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN 
+	NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, 
+	DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, 
+	ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER 
+	DEALINGS IN THE SOFTWARE. -->
 <project xmlns="http://maven.apache.org/POM/4.0.0"
 	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
 	<modelVersion>4.0.0</modelVersion>
-	
+
 	<parent>
 		<groupId>com.iluwatar</groupId>
 		<artifactId>java-design-patterns</artifactId>
-		<version>1.21.0-SNAPSHOT</version>
+		<version>1.23.0-SNAPSHOT</version>
 	</parent>
-	
+
 	<artifactId>acyclic-visitor</artifactId>
 
 	<properties>
@@ -53,24 +44,40 @@
 		<dependency>
 			<groupId>uk.org.lidalia</groupId>
 			<artifactId>slf4j-test</artifactId>
-			<version>1.0.0</version>
+			<version>1.2.0</version>
 			<scope>test</scope>
 		</dependency>
 		<dependency>
-      		<groupId>org.junit.jupiter</groupId>
-      		<artifactId>junit-jupiter-api</artifactId>
-      		<scope>test</scope>
-    	</dependency>
-    	<dependency>
-      		<groupId>org.junit.jupiter</groupId>
-      		<artifactId>junit-jupiter-engine</artifactId>
-      		<scope>test</scope>
-    	</dependency>
+			<groupId>org.junit.jupiter</groupId>
+			<artifactId>junit-jupiter-engine</artifactId>
+			<scope>test</scope>
+		</dependency>
 		<dependency>
 			<groupId>org.mockito</groupId>
 			<artifactId>mockito-all</artifactId>
-			<version>1.9.5</version>
+			<version>1.10.19</version>
 			<scope>test</scope>
 		</dependency>
 	</dependencies>
+	<build>
+    <plugins>
+      <!-- Maven assembly plugin is invoked with default setting which we have 
+        in parent pom and specifying the class having main method -->
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-assembly-plugin</artifactId>
+        <executions>
+          <execution>
+            <configuration>
+              <archive>
+                <manifest>
+                  <mainClass>com.iluwatar.acyclicvisitor.App</mainClass>
+                </manifest>
+              </archive>
+            </configuration>
+          </execution>
+        </executions>
+      </plugin>
+    </plugins>
+  </build>
 </project>

acyclic-visitor/src/main/java/com/iluwatar/acyclicvisitor/AllModemVisitor.java

@@ -1,6 +1,6 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
+ * Copyright © 2014-2019 Ilkka Seppälä
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -20,12 +20,13 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.acyclicvisitor;
 
 /**
- * All ModemVisitor interface extends all visitor interfaces. This interface
- * provides ease of use when a visitor needs to visit all modem types.
+ * All ModemVisitor interface extends all visitor interfaces. This interface provides ease of use
+ * when a visitor needs to visit all modem types.
  */
-public interface AllModemVisitor extends ZoomVisitor, HayesVisitor{
+public interface AllModemVisitor extends ZoomVisitor, HayesVisitor {
 
 }

acyclic-visitor/src/main/java/com/iluwatar/acyclicvisitor/App.java

@@ -1,6 +1,6 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
+ * Copyright © 2014-2019 Ilkka Seppälä
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -20,34 +20,33 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.acyclicvisitor;
 
 /**
- * The Acyclic Visitor pattern allows new functions to be added to existing class 
- * hierarchies without affecting those hierarchies, and without creating the dependency 
- * cycles that are inherent to the GoF Visitor pattern, by making the Visitor base class 
- * degenerate
- * <p>
- * In this example the visitor base class is {@link ModemVisitor}. The base class of the 
- * visited hierarchy is {@link Modem} and has two children {@link Hayes} and {@link Zoom} 
- * each one having its own visitor interface {@link HayesVisitor} and {@link ZoomVisitor} 
- * respectively. {@link ConfigureForUnixVisitor} and {@link ConfigureForDosVisitor} 
- * implement each derivative's visit method only if it is required 
+ * The Acyclic Visitor pattern allows new functions to be added to existing class hierarchies
+ * without affecting those hierarchies, and without creating the dependency cycles that are inherent
+ * to the GoF Visitor pattern, by making the Visitor base class degenerate
+ *
+ * <p>In this example the visitor base class is {@link ModemVisitor}. The base class of the visited
+ * hierarchy is {@link Modem} and has two children {@link Hayes} and {@link Zoom} each one having
+ * its own visitor interface {@link HayesVisitor} and {@link ZoomVisitor} respectively. {@link
+ * ConfigureForUnixVisitor} and {@link ConfigureForDosVisitor} implement each derivative's visit
+ * method only if it is required
  */
 public class App {
-  
+
   /**
-   * Program's entry point
+   * Program's entry point.
    */
-  
-  public static void main(String[] args) {  
-    ConfigureForUnixVisitor conUnix = new ConfigureForUnixVisitor();
-    ConfigureForDosVisitor conDos = new ConfigureForDosVisitor();
-    
-    Zoom zoom = new Zoom();
-    Hayes hayes = new Hayes();
-    
-    hayes.accept(conDos); // Hayes modem with Unix configurator
+  public static void main(String[] args) {
+    var conUnix = new ConfigureForUnixVisitor();
+    var conDos = new ConfigureForDosVisitor();
+
+    var zoom = new Zoom();
+    var hayes = new Hayes();
+
+    hayes.accept(conDos); // Hayes modem with Dos configurator
     zoom.accept(conDos); // Zoom modem with Dos configurator
     hayes.accept(conUnix); // Hayes modem with Unix configurator
     zoom.accept(conUnix); // Zoom modem with Unix configurator   

acyclic-visitor/src/main/java/com/iluwatar/acyclicvisitor/ConfigureForDosVisitor.java

@@ -1,6 +1,6 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
+ * Copyright © 2014-2019 Ilkka Seppälä
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -20,23 +20,26 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.acyclicvisitor;
 
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 /**
- * ConfigureForDosVisitor class implements both zoom's and  hayes' visit method 
- * for Dos manufacturer
+ * ConfigureForDosVisitor class implements both zoom's and  hayes' visit method for Dos
+ * manufacturer.
  */
 public class ConfigureForDosVisitor implements AllModemVisitor {
 
   private static final Logger LOGGER = LoggerFactory.getLogger(ConfigureForDosVisitor.class);
 
+  @Override
   public void visit(Hayes hayes) {
     LOGGER.info(hayes + " used with Dos configurator.");
   }
 
+  @Override
   public void visit(Zoom zoom) {
     LOGGER.info(zoom + " used with Dos configurator.");
   }

acyclic-visitor/src/main/java/com/iluwatar/acyclicvisitor/ConfigureForUnixVisitor.java

@@ -1,6 +1,6 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
+ * Copyright © 2014-2019 Ilkka Seppälä
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -20,20 +20,21 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.acyclicvisitor;
 
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 /**
- * ConfigureForUnixVisitor class implements zoom's visit method for Unix 
- * manufacturer, unlike traditional visitor pattern, this class may selectively implement
- * visit for other modems.
+ * ConfigureForUnixVisitor class implements zoom's visit method for Unix manufacturer, unlike
+ * traditional visitor pattern, this class may selectively implement visit for other modems.
  */
 public class ConfigureForUnixVisitor implements ZoomVisitor {
 
   private static final Logger LOGGER = LoggerFactory.getLogger(ConfigureForUnixVisitor.class);
 
+  @Override
   public void visit(Zoom zoom) {
     LOGGER.info(zoom + " used with Unix configurator.");
   }

acyclic-visitor/src/main/java/com/iluwatar/acyclicvisitor/Hayes.java

@@ -1,6 +1,6 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
+ * Copyright © 2014-2019 Ilkka Seppälä
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -20,20 +20,21 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.acyclicvisitor;
 
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 /**
- * Hayes class implements its accept method
+ * Hayes class implements its accept method.
  */
 public class Hayes extends Modem {
-  
+
   private static final Logger LOGGER = LoggerFactory.getLogger(ConfigureForDosVisitor.class);
 
   /**
-   * Accepts all visitors but honors only HayesVisitor
+   * Accepts all visitors but honors only HayesVisitor.
    */
   @Override
   public void accept(ModemVisitor modemVisitor) {
@@ -44,10 +45,9 @@ public class Hayes extends Modem {
     }
 
   }
-  
+
   /**
-   * Hayes' modem's toString
-   * method
+   * Hayes' modem's toString method.
    */
   @Override
   public String toString() {

acyclic-visitor/src/main/java/com/iluwatar/acyclicvisitor/HayesVisitor.java

@@ -1,6 +1,6 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
+ * Copyright © 2014-2019 Ilkka Seppälä
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -20,10 +20,11 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.acyclicvisitor;
 
 /**
- * HayesVisitor interface
+ * HayesVisitor interface.
  */
 public interface HayesVisitor extends ModemVisitor {
   void visit(Hayes hayes);

acyclic-visitor/src/main/java/com/iluwatar/acyclicvisitor/Modem.java

@@ -1,6 +1,6 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
+ * Copyright © 2014-2019 Ilkka Seppälä
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -20,10 +20,11 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.acyclicvisitor;
 
 /**
- * Modem abstract class
+ * Modem abstract class.
  */
 public abstract class Modem {
   public abstract void accept(ModemVisitor modemVisitor);

acyclic-visitor/src/main/java/com/iluwatar/acyclicvisitor/ModemVisitor.java

@@ -1,6 +1,6 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
+ * Copyright © 2014-2019 Ilkka Seppälä
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -20,12 +20,12 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.acyclicvisitor;
 
 /**
- * ModemVisitor interface does not contain any visit methods so that it does not
- * depend on the visited hierarchy. Each derivative's visit method is declared in 
- * its own visitor interface
+ * ModemVisitor interface does not contain any visit methods so that it does not depend on the
+ * visited hierarchy. Each derivative's visit method is declared in its own visitor interface
  */
 public interface ModemVisitor {
   // Visitor is a degenerate base class for all visitors.

acyclic-visitor/src/main/java/com/iluwatar/acyclicvisitor/Zoom.java

@@ -1,6 +1,6 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
+ * Copyright © 2014-2019 Ilkka Seppälä
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -20,33 +20,33 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.acyclicvisitor;
 
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 /**
- * Zoom class implements its accept method
+ * Zoom class implements its accept method.
  */
 public class Zoom extends Modem {
-  
+
   private static final Logger LOGGER = LoggerFactory.getLogger(ConfigureForDosVisitor.class);
 
   /**
-   * Accepts all visitors but honors only ZoomVisitor
+   * Accepts all visitors but honors only ZoomVisitor.
    */
   @Override
   public void accept(ModemVisitor modemVisitor) {
-    if (modemVisitor instanceof  ZoomVisitor) {
+    if (modemVisitor instanceof ZoomVisitor) {
       ((ZoomVisitor) modemVisitor).visit(this);
     } else {
       LOGGER.info("Only ZoomVisitor is allowed to visit Zoom modem");
     }
   }
-  
+
   /**
-   * Zoom modem's toString
-   * method
+   * Zoom modem's toString method.
    */
   @Override
   public String toString() {

acyclic-visitor/src/main/java/com/iluwatar/acyclicvisitor/ZoomVisitor.java

@@ -1,6 +1,6 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
+ * Copyright © 2014-2019 Ilkka Seppälä
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -20,10 +20,11 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.acyclicvisitor;
 
 /**
- * ZoomVisitor interface
+ * ZoomVisitor interface.
  */
 public interface ZoomVisitor extends ModemVisitor {
   void visit(Zoom zoom);

acyclic-visitor/src/main/java/com/iluwatar/acyclicvisitor/module-info.java

@@ -0,0 +1,26 @@
+/*
+ * The MIT License
+ * Copyright © 2014-2019 Ilkka Seppälä
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+module com.iluwatar.acyclicvisitor {
+	requires org.slf4j;
+}

acyclic-visitor/src/test/java/com/iluwatar/acyclicvisitor/AppTest.java

@@ -1,6 +1,6 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
+ * Copyright © 2014-2019 Ilkka Seppälä
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -20,20 +20,18 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.acyclicvisitor;
 
 import org.junit.jupiter.api.Test;
 
-import com.iluwatar.acyclicvisitor.App;
-
 /**
  * Tests that the Acyclic Visitor example runs without errors.
  */
 public class AppTest {
-  
+
   @Test
   public void test() {
-    String[] args = {};
-    App.main(args);  
+    App.main(new String[]{});
   }
 }

acyclic-visitor/src/test/java/com/iluwatar/acyclicvisitor/ConfigureForDosVisitorTest.java

@@ -1,6 +1,6 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
+ * Copyright © 2014-2019 Ilkka Seppälä
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -20,22 +20,15 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.acyclicvisitor;
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.groups.Tuple.tuple;
-import static org.mockito.Mockito.mock;
 import static uk.org.lidalia.slf4jext.Level.INFO;
 
 import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.Test;
-
-import com.iluwatar.acyclicvisitor.ConfigureForDosVisitor;
-import com.iluwatar.acyclicvisitor.Hayes;
-import com.iluwatar.acyclicvisitor.HayesVisitor;
-import com.iluwatar.acyclicvisitor.Zoom;
-import com.iluwatar.acyclicvisitor.ZoomVisitor;
-
 import uk.org.lidalia.slf4jtest.TestLogger;
 import uk.org.lidalia.slf4jtest.TestLoggerFactory;
 
@@ -44,28 +37,30 @@ import uk.org.lidalia.slf4jtest.TestLoggerFactory;
  */
 public class ConfigureForDosVisitorTest {
 
-  TestLogger logger = TestLoggerFactory.getTestLogger(ConfigureForDosVisitor.class);
+  private TestLogger logger = TestLoggerFactory.getTestLogger(ConfigureForDosVisitor.class);
   
   @Test
   public void testVisitForZoom() {    
-    ConfigureForDosVisitor conDos = new ConfigureForDosVisitor();
-    Zoom zoom = new Zoom();
+    var conDos = new ConfigureForDosVisitor();
+    var zoom = new Zoom();
     
     conDos.visit(zoom);
     
-    assertThat(logger.getLoggingEvents()).extracting("level", "message").contains(
-        tuple(INFO, zoom + " used with Dos configurator."));
+    assertThat(logger.getLoggingEvents())
+        .extracting("level", "message")
+        .contains(tuple(INFO, zoom + " used with Dos configurator."));
   }
   
   @Test
   public void testVisitForHayes() {
-    ConfigureForDosVisitor conDos = new ConfigureForDosVisitor();
-    Hayes hayes = new Hayes();
+    var conDos = new ConfigureForDosVisitor();
+    var hayes = new Hayes();
     
     conDos.visit(hayes);
     
-    assertThat(logger.getLoggingEvents()).extracting("level", "message").contains(
-        tuple(INFO, hayes + " used with Dos configurator."));
+    assertThat(logger.getLoggingEvents())
+        .extracting("level", "message")
+        .contains(tuple(INFO, hayes + " used with Dos configurator."));
   }
   
   @AfterEach

acyclic-visitor/src/test/java/com/iluwatar/acyclicvisitor/ConfigureForUnixVisitorTest.java

@@ -1,6 +1,6 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
+ * Copyright © 2014-2019 Ilkka Seppälä
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -20,32 +20,25 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.acyclicvisitor;
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.groups.Tuple.tuple;
 import static uk.org.lidalia.slf4jext.Level.INFO;
-import static org.mockito.Mockito.mock;
+
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.Test;
 
 import uk.org.lidalia.slf4jtest.TestLogger;
 import uk.org.lidalia.slf4jtest.TestLoggerFactory;
-import org.junit.jupiter.api.Test;
-
-import com.iluwatar.acyclicvisitor.ConfigureForUnixVisitor;
-import com.iluwatar.acyclicvisitor.Hayes;
-import com.iluwatar.acyclicvisitor.HayesVisitor;
-import com.iluwatar.acyclicvisitor.Zoom;
-import com.iluwatar.acyclicvisitor.ZoomVisitor;
-
-import org.junit.jupiter.api.AfterEach;
-import org.junit.jupiter.api.Assertions;
 
 /**
  * ConfigureForUnixVisitor test class
  */
 public class ConfigureForUnixVisitorTest {
   
-  TestLogger logger = TestLoggerFactory.getTestLogger(ConfigureForUnixVisitor.class);
+  private static final TestLogger LOGGER = TestLoggerFactory.getTestLogger(ConfigureForUnixVisitor.class);
   
   @AfterEach
   public void clearLoggers() {
@@ -54,12 +47,13 @@ public class ConfigureForUnixVisitorTest {
   
   @Test
   public void testVisitForZoom() {
-    ConfigureForUnixVisitor conUnix = new ConfigureForUnixVisitor();
-    Zoom zoom = new Zoom();
+    var conUnix = new ConfigureForUnixVisitor();
+    var zoom = new Zoom();
     
     conUnix.visit(zoom);
     
-    assertThat(logger.getLoggingEvents()).extracting("level", "message").contains(
-        tuple(INFO, zoom + " used with Unix configurator."));
+    assertThat(LOGGER.getLoggingEvents())
+        .extracting("level", "message")
+        .contains(tuple(INFO, zoom + " used with Unix configurator."));
   }
 }

acyclic-visitor/src/test/java/com/iluwatar/acyclicvisitor/HayesTest.java

@@ -1,6 +1,6 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
+ * Copyright © 2014-2019 Ilkka Seppälä
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -20,6 +20,7 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.acyclicvisitor;
 
 import static org.mockito.Matchers.eq;
@@ -29,11 +30,6 @@ import static org.mockito.Mockito.verifyZeroInteractions;
 
 import org.junit.jupiter.api.Test;
 
-import com.iluwatar.acyclicvisitor.ConfigureForDosVisitor;
-import com.iluwatar.acyclicvisitor.ConfigureForUnixVisitor;
-import com.iluwatar.acyclicvisitor.Hayes;
-import com.iluwatar.acyclicvisitor.HayesVisitor;
-
 /**
  * Hayes test class
  */
@@ -41,8 +37,8 @@ public class HayesTest {
 
   @Test
   public void testAcceptForDos() {  
-    Hayes hayes = new Hayes();
-    ConfigureForDosVisitor mockVisitor = mock(ConfigureForDosVisitor.class);
+    var hayes = new Hayes();
+    var mockVisitor = mock(ConfigureForDosVisitor.class);
     
     hayes.accept(mockVisitor);
     verify((HayesVisitor)mockVisitor).visit(eq(hayes));
@@ -50,8 +46,8 @@ public class HayesTest {
   
   @Test
   public void testAcceptForUnix() {    
-    Hayes hayes = new Hayes();
-    ConfigureForUnixVisitor mockVisitor = mock(ConfigureForUnixVisitor.class);
+    var hayes = new Hayes();
+    var mockVisitor = mock(ConfigureForUnixVisitor.class);
     
     hayes.accept(mockVisitor);
     

acyclic-visitor/src/test/java/com/iluwatar/acyclicvisitor/ZoomTest.java

@@ -1,6 +1,6 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
+ * Copyright © 2014-2019 Ilkka Seppälä
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -20,6 +20,7 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.acyclicvisitor;
 
 
@@ -29,11 +30,6 @@ import static org.mockito.Mockito.mock;
 
 import org.junit.jupiter.api.Test;
 
-import com.iluwatar.acyclicvisitor.ConfigureForDosVisitor;
-import com.iluwatar.acyclicvisitor.ConfigureForUnixVisitor;
-import com.iluwatar.acyclicvisitor.Zoom;
-import com.iluwatar.acyclicvisitor.ZoomVisitor;
-
 /**
  * Zoom test class
  */
@@ -41,8 +37,8 @@ public class ZoomTest {
   
   @Test
   public void testAcceptForDos() {  
-    Zoom zoom = new Zoom();
-    ConfigureForDosVisitor mockVisitor = mock(ConfigureForDosVisitor.class);
+    var zoom = new Zoom();
+    var mockVisitor = mock(ConfigureForDosVisitor.class);
     
     zoom.accept(mockVisitor);
     verify((ZoomVisitor)mockVisitor).visit(eq(zoom));
@@ -50,8 +46,8 @@ public class ZoomTest {
   
   @Test
   public void testAcceptForUnix() {
-    Zoom zoom = new Zoom();
-    ConfigureForUnixVisitor mockVisitor = mock(ConfigureForUnixVisitor.class);
+    var zoom = new Zoom();
+    var mockVisitor = mock(ConfigureForUnixVisitor.class);
     
     zoom.accept(mockVisitor);
     verify((ZoomVisitor)mockVisitor).visit(eq(zoom));

adapter/README.md

@@ -5,9 +5,7 @@ folder: adapter
 permalink: /patterns/adapter/
 categories: Structural
 tags:
- - Java
- - Gang Of Four
- - Difficulty-Beginner
+ - Gang of Four
 ---
 
 ## Also known as
@@ -56,15 +54,14 @@ public class FishingBoat {
 And captain expects an implementation of `RowingBoat` interface to be able to move
 
 ```java
-public class Captain implements RowingBoat {
+public class Captain {
 
   private RowingBoat rowingBoat;
-
+  // default constructor and setter for rowingBoat
   public Captain(RowingBoat rowingBoat) {
     this.rowingBoat = rowingBoat;
   }
 
-  @Override
   public void row() {
     rowingBoat.row();
   }
@@ -94,10 +91,13 @@ public class FishingBoatAdapter implements RowingBoat {
 And now the `Captain` can use the `FishingBoat` to escape the pirates.
 
 ```java
-Captain captain = new Captain(new FishingBoatAdapter());
+var captain = new Captain(new FishingBoatAdapter());
 captain.row();
 ```
 
+## Class diagram
+![alt text](./etc/adapter.urm.png "Adapter class diagram")
+
 ## Applicability
 Use the Adapter pattern when
 
@@ -129,5 +129,7 @@ An object adapter
 
 ## Credits
 
-* [Design Patterns: Elements of Reusable Object-Oriented Software](http://www.amazon.com/Design-Patterns-Elements-Reusable-Object-Oriented/dp/0201633612)
-* [J2EE Design Patterns](http://www.amazon.com/J2EE-Design-Patterns-William-Crawford/dp/0596004273/ref=sr_1_2)
+* [Design Patterns: Elements of Reusable Object-Oriented Software](https://www.amazon.com/gp/product/0201633612/ref=as_li_tl?ie=UTF8&camp=1789&creative=9325&creativeASIN=0201633612&linkCode=as2&tag=javadesignpat-20&linkId=675d49790ce11db99d90bde47f1aeb59)
+* [J2EE Design Patterns](https://www.amazon.com/gp/product/0596004273/ref=as_li_tl?ie=UTF8&camp=1789&creative=9325&creativeASIN=0596004273&linkCode=as2&tag=javadesignpat-20&linkId=48d37c67fb3d845b802fa9b619ad8f31)
+* [Head First Design Patterns: A Brain-Friendly Guide](https://www.amazon.com/gp/product/0596007124/ref=as_li_tl?ie=UTF8&camp=1789&creative=9325&creativeASIN=0596007124&linkCode=as2&tag=javadesignpat-20&linkId=6b8b6eea86021af6c8e3cd3fc382cb5b)
+* [Refactoring to Patterns](https://www.amazon.com/gp/product/0321213351/ref=as_li_tl?ie=UTF8&camp=1789&creative=9325&creativeASIN=0321213351&linkCode=as2&tag=javadesignpat-20&linkId=2a76fcb387234bc71b1c61150b3cc3a7)

adapter/etc/adapter.urm.puml

@@ -0,0 +1,31 @@
+@startuml
+package com.iluwatar.adapter {
+  class App {
+    - App()
+    + main(args : String[]) {static}
+  }
+  class Captain {
+    - rowingBoat : RowingBoat
+    + Captain()
+    + Captain(boat : RowingBoat)
+    ~ row()
+    ~ setRowingBoat(boat : RowingBoat)
+  }
+  ~class FishingBoat {
+    - LOGGER : Logger {static}
+    ~ FishingBoat()
+    ~ sail()
+  }
+  class FishingBoatAdapter {
+    - boat : FishingBoat
+    + FishingBoatAdapter()
+    + row()
+  }
+  interface RowingBoat {
+    + row() {abstract}
+  }
+}
+FishingBoatAdapter -->  "-boat" FishingBoat
+Captain -->  "-rowingBoat" RowingBoat
+FishingBoatAdapter ..|> RowingBoat 
+@enduml

adapter/pom.xml

@@ -1,52 +1,61 @@
 <?xml version="1.0"?>
-<!--
-
-    The MIT License
-    Copyright (c) 2014-2016 Ilkka Seppälä
-
-    Permission is hereby granted, free of charge, to any person obtaining a copy
-    of this software and associated documentation files (the "Software"), to deal
-    in the Software without restriction, including without limitation the rights
-    to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-    copies of the Software, and to permit persons to whom the Software is
-    furnished to do so, subject to the following conditions:
-
-    The above copyright notice and this permission notice shall be included in
-    all copies or substantial portions of the Software.
-
-    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-    IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-    AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-    OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
-    THE SOFTWARE.
-
--->
-<project xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd" xmlns="http://maven.apache.org/POM/4.0.0"
-    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
-  <modelVersion>4.0.0</modelVersion>
-  <parent>
-    <groupId>com.iluwatar</groupId>
-    <artifactId>java-design-patterns</artifactId>
-    <version>1.21.0-SNAPSHOT</version>
-  </parent>
-  <artifactId>adapter</artifactId>
-  <dependencies>
-    <dependency>
-      <groupId>org.junit.jupiter</groupId>
-      <artifactId>junit-jupiter-api</artifactId>
-      <scope>test</scope>
-    </dependency>
-    <dependency>
-      <groupId>org.junit.jupiter</groupId>
-      <artifactId>junit-jupiter-engine</artifactId>
-      <scope>test</scope>
-    </dependency>
-    <dependency>
-      <groupId>org.mockito</groupId>
-      <artifactId>mockito-core</artifactId>
-      <scope>test</scope>
-    </dependency>
-  </dependencies>
+<!-- The MIT License Copyright © 2014-2019 Ilkka Seppälä Permission is hereby 
+	granted, free of charge, to any person obtaining a copy of this software 
+	and associated documentation files (the "Software"), to deal in the Software 
+	without restriction, including without limitation the rights to use, copy, 
+	modify, merge, publish, distribute, sublicense, and/or sell copies of the 
+	Software, and to permit persons to whom the Software is furnished to do so, 
+	subject to the following conditions: The above copyright notice and this 
+	permission notice shall be included in all copies or substantial portions 
+	of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY 
+	KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 
+	MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN 
+	NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, 
+	DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, 
+	ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER 
+	DEALINGS IN THE SOFTWARE. -->
+<project
+	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"
+	xmlns="http://maven.apache.org/POM/4.0.0"
+	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
+	<modelVersion>4.0.0</modelVersion>
+	<parent>
+		<groupId>com.iluwatar</groupId>
+		<artifactId>java-design-patterns</artifactId>
+		<version>1.23.0-SNAPSHOT</version>
+	</parent>
+	<artifactId>adapter</artifactId>
+	<dependencies>
+		<dependency>
+			<groupId>org.junit.jupiter</groupId>
+			<artifactId>junit-jupiter-engine</artifactId>
+			<scope>test</scope>
+		</dependency>
+		<dependency>
+			<groupId>org.mockito</groupId>
+			<artifactId>mockito-core</artifactId>
+			<scope>test</scope>
+		</dependency>
+	</dependencies>
+	<build>
+		<plugins>
+			<!-- Maven assembly plugin is invoked with default setting which we have 
+				in parent pom and specifying the class having main method -->
+			<plugin>
+				<groupId>org.apache.maven.plugins</groupId>
+				<artifactId>maven-assembly-plugin</artifactId>
+				<executions>
+					<execution>
+						<configuration>
+							<archive>
+								<manifest>
+									<mainClass>com.iluwatar.adapter.App</mainClass>
+								</manifest>
+							</archive>
+						</configuration>
+					</execution>
+				</executions>
+			</plugin>
+		</plugins>
+	</build>
 </project>

adapter/src/main/java/com/iluwatar/adapter/App.java

@@ -1,6 +1,6 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
+ * Copyright © 2014-2019 Ilkka Seppälä
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -20,6 +20,7 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.adapter;
 
 /**
@@ -28,33 +29,33 @@ package com.iluwatar.adapter;
  * The Adapter design pattern allows otherwise incompatible classes to work together by converting
  * the interface of one class into an interface expected by the clients.
  *
- * <p>
- * There are two variations of the Adapter pattern: The class adapter implements the adaptee's
+ * <p>There are two variations of the Adapter pattern: The class adapter implements the adaptee's
  * interface whereas the object adapter uses composition to contain the adaptee in the adapter
  * object. This example uses the object adapter approach.
  *
- * <p>
- * The Adapter ({@link FishingBoatAdapter}) converts the interface of the adaptee class (
- * {@link FishingBoat}) into a suitable one expected by the client ( {@link RowingBoat} ).
- *
- * <p>
- * The story of this implementation is this. <br>
- * Pirates are coming! we need a {@link RowingBoat} to flee! We have a {@link FishingBoat} and our
- * captain. We have no time to make up a new ship! we need to reuse this {@link FishingBoat}. The
- * captain needs a rowing boat which he can operate. The spec is in {@link RowingBoat}. We will
- * use the Adapter pattern to reuse {@link FishingBoat}.
+ * <p>The Adapter ({@link FishingBoatAdapter}) converts the interface of the adaptee class ({@link
+ * FishingBoat}) into a suitable one expected by the client ({@link RowingBoat}).
  *
+ * <p>The story of this implementation is this. <br> Pirates are coming! we need a {@link
+ * RowingBoat} to flee! We have a {@link FishingBoat} and our captain. We have no time to make up a
+ * new ship! we need to reuse this {@link FishingBoat}. The captain needs a rowing boat which he can
+ * operate. The spec is in {@link RowingBoat}. We will use the Adapter pattern to reuse {@link
+ * FishingBoat}.
  */
-public class App {
+public final class App {
+
+  private App() {
+  }
 
   /**
    * Program entry point.
    *
    * @param args command line args
    */
-  public static void main(String[] args) {
-    // The captain can only operate rowing boats but with adapter he is able to use fishing boats as well
-    Captain captain = new Captain(new FishingBoatAdapter());
+  public static void main(final String[] args) {
+    // The captain can only operate rowing boats but with adapter he is able to
+    // use fishing boats as well
+    var captain = new Captain(new FishingBoatAdapter());
     captain.row();
   }
 }

adapter/src/main/java/com/iluwatar/adapter/Captain.java

@@ -1,6 +1,6 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
+ * Copyright © 2014-2019 Ilkka Seppälä
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -20,27 +20,28 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.adapter;
 
 /**
- * The Captain uses {@link RowingBoat} to sail. <br>
- * This is the client in the pattern.
+ * The Captain uses {@link RowingBoat} to sail. <br> This is the client in the pattern.
  */
-public class Captain {
+public final class Captain {
 
   private RowingBoat rowingBoat;
 
-  public Captain() {}
-
-  public Captain(RowingBoat rowingBoat) {
-    this.rowingBoat = rowingBoat;
+  public Captain() {
   }
 
-  public void setRowingBoat(RowingBoat rowingBoat) {
-    this.rowingBoat = rowingBoat;
+  public Captain(final RowingBoat boat) {
+    this.rowingBoat = boat;
   }
 
-  public void row() {
+  void setRowingBoat(final RowingBoat boat) {
+    this.rowingBoat = boat;
+  }
+
+  void row() {
     rowingBoat.row();
   }
 

adapter/src/main/java/com/iluwatar/adapter/FishingBoat.java

@@ -1,6 +1,6 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
+ * Copyright © 2014-2019 Ilkka Seppälä
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -20,22 +20,22 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.adapter;
 
+import static org.slf4j.LoggerFactory.getLogger;
+
 import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
 
 /**
- *
- * Device class (adaptee in the pattern). We want to reuse this class.
- * Fishing boat moves by sailing.
- *
+ * Device class (adaptee in the pattern). We want to reuse this class. Fishing boat moves by
+ * sailing.
  */
-public class FishingBoat {
+final class FishingBoat {
 
-  private static final Logger LOGGER = LoggerFactory.getLogger(FishingBoat.class);
+  private static final Logger LOGGER = getLogger(FishingBoat.class);
 
-  public void sail() {
+  void sail() {
     LOGGER.info("The fishing boat is sailing");
   }
 

adapter/src/main/java/com/iluwatar/adapter/FishingBoatAdapter.java

@@ -1,6 +1,6 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
+ * Copyright © 2014-2019 Ilkka Seppälä
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -20,13 +20,12 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.adapter;
 
 /**
- *
  * Adapter class. Adapts the interface of the device ({@link FishingBoat}) into {@link RowingBoat}
  * interface expected by the client ({@link Captain}).
- *
  */
 public class FishingBoatAdapter implements RowingBoat {
 
@@ -36,8 +35,7 @@ public class FishingBoatAdapter implements RowingBoat {
     boat = new FishingBoat();
   }
 
-  @Override
-  public void row() {
+  public final void row() {
     boat.sail();
   }
 }

adapter/src/main/java/com/iluwatar/adapter/RowingBoat.java

@@ -1,6 +1,6 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
+ * Copyright © 2014-2019 Ilkka Seppälä
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -20,12 +20,11 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.adapter;
 
 /**
- * The interface expected by the client.<br>
- * A rowing boat is rowed to move.
- *
+ * The interface expected by the client.<br> A rowing boat is rowed to move.
  */
 public interface RowingBoat {
 

adapter/src/main/java/com/iluwatar/adapter/package-info.java

@@ -0,0 +1,24 @@
+/*
+ * The MIT License
+ * Copyright © 2014-2019 Ilkka Seppälä
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+package com.iluwatar.adapter;

adapter/src/test/java/com/iluwatar/adapter/AdapterPatternTest.java

@@ -1,6 +1,6 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
+ * Copyright © 2014-2019 Ilkka Seppälä
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -20,20 +20,19 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.adapter;
 
-import org.junit.jupiter.api.BeforeEach;
-import org.junit.jupiter.api.Test;
-
-import java.util.HashMap;
-import java.util.Map;
-
 import static org.mockito.Mockito.spy;
 import static org.mockito.Mockito.verify;
 
+import java.util.HashMap;
+import java.util.Map;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
 /**
  * Test class
- * 
  */
 public class AdapterPatternTest {
 
@@ -50,29 +49,29 @@ public class AdapterPatternTest {
   public void setup() {
     beans = new HashMap<>();
 
-    FishingBoatAdapter fishingBoatAdapter = spy(new FishingBoatAdapter());
+    var fishingBoatAdapter = spy(new FishingBoatAdapter());
     beans.put(FISHING_BEAN, fishingBoatAdapter);
 
-    Captain captain = new Captain();
+    var captain = new Captain();
     captain.setRowingBoat((FishingBoatAdapter) beans.get(FISHING_BEAN));
     beans.put(ROWING_BEAN, captain);
   }
 
   /**
-   * This test asserts that when we use the row() method on a captain bean(client), it is
-   * internally calling sail method on the fishing boat object. The Adapter ({@link FishingBoatAdapter}
-   * ) converts the interface of the target class ( {@link FishingBoat}) into a suitable one
-   * expected by the client ({@link Captain} ).
+   * This test asserts that when we use the row() method on a captain bean(client), it is internally
+   * calling sail method on the fishing boat object. The Adapter ({@link FishingBoatAdapter} )
+   * converts the interface of the target class ( {@link FishingBoat}) into a suitable one expected
+   * by the client ({@link Captain} ).
    */
   @Test
   public void testAdapter() {
-    Captain captain = (Captain) beans.get(ROWING_BEAN);
+    var captain = (Captain) beans.get(ROWING_BEAN);
 
     // when captain moves
     captain.row();
 
     // the captain internally calls the battleship object to move
-    RowingBoat adapter = (RowingBoat) beans.get(FISHING_BEAN);
+    var adapter = (RowingBoat) beans.get(FISHING_BEAN);
     verify(adapter).row();
   }
 }

adapter/src/test/java/com/iluwatar/adapter/AppTest.java

@@ -1,6 +1,6 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
+ * Copyright © 2014-2019 Ilkka Seppälä
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -20,19 +20,17 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.adapter;
 
 import org.junit.jupiter.api.Test;
 
-import java.io.IOException;
-
 /**
  * Tests that Adapter example runs without errors.
  */
 public class AppTest {
   @Test
-  public void test() throws IOException {
-    String[] args = {};
-    App.main(args);
+  public void test() {
+    App.main(new String[]{});
   }
 }

aggregator-microservices/README.md

@@ -5,8 +5,7 @@ folder: aggregator-microservices
 permalink: /patterns/aggregator-microservices/
 categories: Architectural
 tags:
-- Java
-- Spring
+- Cloud distributed
 ---
 
 ## Intent
@@ -18,6 +17,8 @@ More variations of the aggregator are:
 - Chained Microservice Design Pattern: In this case each microservice is dependent/ chained to a series 
 of other microservices.
 
+## Class diagram
+
 ![alt text](./etc/aggregator-microservice.png "Aggregator Microservice")
 
 ## Applicability
@@ -26,4 +27,4 @@ Use the Aggregator Microservices pattern when you need a unified API for various
 
 ## Credits
 
-* [Microservice Design Patterns](http://blog.arungupta.me/microservice-design-patterns/)
+* [Microservice Design Patterns](http://web.archive.org/web/20190705163602/http://blog.arungupta.me/microservice-design-patterns/)

aggregator-microservices/aggregator-service/etc/aggregator-service.urm.puml

@@ -0,0 +1,43 @@
+@startuml
+package com.iluwatar.aggregator.microservices {
+  class Aggregator {
+    - informationClient : ProductInformationClient
+    - inventoryClient : ProductInventoryClient
+    + Aggregator()
+    + getProduct() : Product
+  }
+  class App {
+    + App()
+    + main(args : String[]) {static}
+  }
+  class Product {
+    - productInventories : int
+    - title : String
+    + Product()
+    + getProductInventories() : int
+    + getTitle() : String
+    + setProductInventories(productInventories : int)
+    + setTitle(title : String)
+  }
+  interface ProductInformationClient {
+    + getProductTitle() : String {abstract}
+  }
+  class ProductInformationClientImpl {
+    - LOGGER : Logger {static}
+    + ProductInformationClientImpl()
+    + getProductTitle() : String
+  }
+  interface ProductInventoryClient {
+    + getProductInventories() : Integer {abstract}
+  }
+  class ProductInventoryClientImpl {
+    - LOGGER : Logger {static}
+    + ProductInventoryClientImpl()
+    + getProductInventories() : Integer
+  }
+}
+Aggregator -->  "-informationClient" ProductInformationClient
+Aggregator -->  "-inventoryClient" ProductInventoryClient
+ProductInformationClientImpl ..|> ProductInformationClient 
+ProductInventoryClientImpl ..|> ProductInventoryClient 
+@enduml

aggregator-microservices/aggregator-service/pom.xml

@@ -1,93 +1,81 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<!--
-
-    The MIT License
-    Copyright (c) 2014-2016 Ilkka Seppälä
-
-    Permission is hereby granted, free of charge, to any person obtaining a copy
-    of this software and associated documentation files (the "Software"), to deal
-    in the Software without restriction, including without limitation the rights
-    to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-    copies of the Software, and to permit persons to whom the Software is
-    furnished to do so, subject to the following conditions:
-
-    The above copyright notice and this permission notice shall be included in
-    all copies or substantial portions of the Software.
-
-    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-    IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-    AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-    OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
-    THE SOFTWARE.
-
--->
+<!-- The MIT License Copyright © 2014-2019 Ilkka Seppälä Permission is hereby 
+	granted, free of charge, to any person obtaining a copy of this software 
+	and associated documentation files (the "Software"), to deal in the Software 
+	without restriction, including without limitation the rights to use, copy, 
+	modify, merge, publish, distribute, sublicense, and/or sell copies of the 
+	Software, and to permit persons to whom the Software is furnished to do so, 
+	subject to the following conditions: The above copyright notice and this 
+	permission notice shall be included in all copies or substantial portions 
+	of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY 
+	KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 
+	MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN 
+	NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, 
+	DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, 
+	ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER 
+	DEALINGS IN THE SOFTWARE. -->
 <project xmlns="http://maven.apache.org/POM/4.0.0"
-         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
-    <parent>
-        <artifactId>aggregator-microservices</artifactId>
-        <groupId>com.iluwatar</groupId>
-        <version>1.21.0-SNAPSHOT</version>
-    </parent>
-    <modelVersion>4.0.0</modelVersion>
+	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+	<parent>
+		<artifactId>aggregator-microservices</artifactId>
+		<groupId>com.iluwatar</groupId>
+		<version>1.23.0-SNAPSHOT</version>
+	</parent>
+	<modelVersion>4.0.0</modelVersion>
+	<artifactId>aggregator-service</artifactId>
+	<packaging>jar</packaging>
+	<dependencies>
+		<dependency>
+			<groupId>org.springframework</groupId>
+			<artifactId>spring-webmvc</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-web</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>org.junit.jupiter</groupId>
+			<artifactId>junit-jupiter-engine</artifactId>
+			<scope>test</scope>
+		</dependency>
+		<dependency>
+			<groupId>org.mockito</groupId>
+			<artifactId>mockito-core</artifactId>
+			<scope>test</scope>
+		</dependency>
+	</dependencies>
 
-    <artifactId>aggregator-service</artifactId>
-    <packaging>jar</packaging>
-
-    <dependencyManagement>
-        <dependencies>
-            <dependency>
-                <groupId>org.springframework.boot</groupId>
-                <artifactId>spring-boot-dependencies</artifactId>
-            </dependency>
-        </dependencies>
-    </dependencyManagement>
-    <dependencies>
-        <dependency>
-            <groupId>org.springframework</groupId>
-            <artifactId>spring-webmvc</artifactId>
-        </dependency>
-        <dependency>
-            <groupId>org.springframework.boot</groupId>
-            <artifactId>spring-boot-starter-web</artifactId>
-        </dependency>
-        <dependency>
-            <groupId>org.junit.jupiter</groupId>
-            <artifactId>junit-jupiter-api</artifactId>
-            <scope>test</scope>
-        </dependency>
-        <dependency>
-            <groupId>org.junit.jupiter</groupId>
-            <artifactId>junit-jupiter-engine</artifactId>
-            <scope>test</scope>
-        </dependency>
-        <dependency>
-            <groupId>org.mockito</groupId>
-            <artifactId>mockito-core</artifactId>
-            <scope>test</scope>
-        </dependency>
-        <dependency>
-            <groupId>org.apache.httpcomponents</groupId>
-            <artifactId>httpclient</artifactId>
-        </dependency>
-    </dependencies>
-
-    <build>
-        <plugins>
-            <plugin>
-                <groupId>org.springframework.boot</groupId>
-                <artifactId>spring-boot-maven-plugin</artifactId>
-                <version>${spring-boot.version}</version>
-                <executions>
-                    <execution>
-                        <goals>
-                            <goal>repackage</goal>
-                        </goals>
-                    </execution>
-                </executions>
-            </plugin>
-        </plugins>
-    </build>
-</project>
+	<build>
+		<plugins>
+			<plugin>
+				<groupId>org.springframework.boot</groupId>
+				<artifactId>spring-boot-maven-plugin</artifactId>
+				<executions>
+					<execution>
+						<goals>
+							<goal>repackage</goal>
+						</goals>
+					</execution>
+				</executions>
+			</plugin>
+			<!-- Maven assembly plugin is invoked with default setting which we have 
+				in parent pom and specifying the class having main method -->
+			<plugin>
+				<groupId>org.apache.maven.plugins</groupId>
+				<artifactId>maven-assembly-plugin</artifactId>
+				<executions>
+					<execution>
+						<configuration>
+							<archive>
+								<manifest>
+									<mainClass>com.iluwatar.aggregator.microservices.App</mainClass>
+								</manifest>
+							</archive>
+						</configuration>
+					</execution>
+				</executions>
+			</plugin>
+		</plugins>
+	</build>
+</project>

aggregator-microservices/aggregator-service/src/main/java/com/iluwatar/aggregator/microservices/Aggregator.java

@@ -1,17 +1,17 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
- * <p/>
+ * Copyright © 2014-2019 Ilkka Seppälä
+ *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
  * in the Software without restriction, including without limitation the rights
  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  * copies of the Software, and to permit persons to whom the Software is
  * furnished to do so, subject to the following conditions:
- * <p/>
+ *
  * The above copyright notice and this permission notice shall be included in
  * all copies or substantial portions of the Software.
- * <p/>
+ *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
@@ -20,16 +20,19 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.aggregator.microservices;
 
-import org.springframework.web.bind.annotation.RequestMapping;
-import org.springframework.web.bind.annotation.RestController;
+import static java.util.Objects.requireNonNullElse;
 
 import javax.annotation.Resource;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RequestMethod;
+import org.springframework.web.bind.annotation.RestController;
 
 /**
- * The aggregator aggregates calls on various micro-services, collects
- * data and further publishes them under a REST endpoint.
+ * The aggregator aggregates calls on various micro-services, collects data and further publishes
+ * them under a REST endpoint.
  */
 @RestController
 public class Aggregator {
@@ -47,11 +50,19 @@ public class Aggregator {
    *
    * @return a Product.
    */
-  @RequestMapping("/product")
+  @RequestMapping(path = "/product", method = RequestMethod.GET)
   public Product getProduct() {
-    Product product = new Product();
-    product.setTitle(informationClient.getProductTitle());
-    product.setProductInventories(inventoryClient.getProductInventories());
+
+    var product = new Product();
+    var productTitle = informationClient.getProductTitle();
+    var productInventory = inventoryClient.getProductInventories();
+
+    //Fallback to error message
+    product.setTitle(requireNonNullElse(productTitle, "Error: Fetching Product Title Failed"));
+
+    //Fallback to default error inventory
+    product.setProductInventories(requireNonNullElse(productInventory, -1));
+
     return product;
   }
 

aggregator-microservices/aggregator-service/src/main/java/com/iluwatar/aggregator/microservices/App.java

@@ -1,17 +1,17 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
- * <p/>
+ * Copyright © 2014-2019 Ilkka Seppälä
+ *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
  * in the Software without restriction, including without limitation the rights
  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  * copies of the Software, and to permit persons to whom the Software is
  * furnished to do so, subject to the following conditions:
- * <p/>
+ *
  * The above copyright notice and this permission notice shall be included in
  * all copies or substantial portions of the Software.
- * <p/>
+ *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
@@ -20,19 +20,20 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.aggregator.microservices;
 
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
 
 /**
- * Spring Boot EntryPoint Class
+ * Spring Boot EntryPoint Class.
  */
 @SpringBootApplication
 public class App {
 
   /**
-   * Program entry point
+   * Program entry point.
    *
    * @param args command line args
    */

aggregator-microservices/aggregator-service/src/main/java/com/iluwatar/aggregator/microservices/Product.java

@@ -1,17 +1,17 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
- * <p/>
+ * Copyright © 2014-2019 Ilkka Seppälä
+ *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
  * in the Software without restriction, including without limitation the rights
  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  * copies of the Software, and to permit persons to whom the Software is
  * furnished to do so, subject to the following conditions:
- * <p/>
+ *
  * The above copyright notice and this permission notice shall be included in
  * all copies or substantial portions of the Software.
- * <p/>
+ *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
@@ -20,6 +20,7 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.aggregator.microservices;
 
 /**

aggregator-microservices/aggregator-service/src/main/java/com/iluwatar/aggregator/microservices/ProductInformationClient.java

@@ -1,17 +1,17 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
- * <p/>
+ * Copyright © 2014-2019 Ilkka Seppälä
+ *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
  * in the Software without restriction, including without limitation the rights
  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  * copies of the Software, and to permit persons to whom the Software is
  * furnished to do so, subject to the following conditions:
- * <p/>
+ *
  * The above copyright notice and this permission notice shall be included in
  * all copies or substantial portions of the Software.
- * <p/>
+ *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
@@ -20,6 +20,7 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.aggregator.microservices;
 
 /**

aggregator-microservices/aggregator-service/src/main/java/com/iluwatar/aggregator/microservices/ProductInformationClientImpl.java

@@ -1,17 +1,17 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
- * <p/>
+ * Copyright © 2014-2019 Ilkka Seppälä
+ *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
  * in the Software without restriction, including without limitation the rights
  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  * copies of the Software, and to permit persons to whom the Software is
  * furnished to do so, subject to the following conditions:
- * <p/>
+ *
  * The above copyright notice and this permission notice shall be included in
  * all copies or substantial portions of the Software.
- * <p/>
+ *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
@@ -20,19 +20,18 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.aggregator.microservices;
 
-import org.apache.http.client.methods.CloseableHttpResponse;
-import org.apache.http.client.methods.HttpGet;
-import org.apache.http.impl.client.CloseableHttpClient;
-import org.apache.http.impl.client.HttpClients;
-import org.apache.http.util.EntityUtils;
+import java.io.IOException;
+import java.net.URI;
+import java.net.http.HttpClient;
+import java.net.http.HttpRequest;
+import java.net.http.HttpResponse;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.stereotype.Component;
 
-import java.io.IOException;
-
 /**
  * An adapter to communicate with information micro-service.
  */
@@ -43,15 +42,19 @@ public class ProductInformationClientImpl implements ProductInformationClient {
 
   @Override
   public String getProductTitle() {
-    String response = null;
-    try (CloseableHttpClient httpClient = HttpClients.createDefault()) {
-      HttpGet httpGet = new HttpGet("http://localhost:51515/information");
-      try (CloseableHttpResponse httpResponse = httpClient.execute(httpGet)) {
-        response = EntityUtils.toString(httpResponse.getEntity());
-      }
-    } catch (IOException e) {
-      LOGGER.error("Exception caught.", e);
+    var request = HttpRequest.newBuilder()
+        .GET()
+        .uri(URI.create("http://localhost:51515/information"))
+        .build();
+    var client = HttpClient.newHttpClient();
+    try {
+      var httpResponse = client.send(request, HttpResponse.BodyHandlers.ofString());
+      return httpResponse.body();
+    } catch (IOException ioe) {
+      LOGGER.error("IOException Occurred", ioe);
+    } catch (InterruptedException ie) {
+      LOGGER.error("InterruptedException Occurred", ie);
     }
-    return response;
+    return null;
   }
 }

aggregator-microservices/aggregator-service/src/main/java/com/iluwatar/aggregator/microservices/ProductInventoryClient.java

@@ -1,17 +1,17 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
- * <p/>
+ * Copyright © 2014-2019 Ilkka Seppälä
+ *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
  * in the Software without restriction, including without limitation the rights
  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  * copies of the Software, and to permit persons to whom the Software is
  * furnished to do so, subject to the following conditions:
- * <p/>
+ *
  * The above copyright notice and this permission notice shall be included in
  * all copies or substantial portions of the Software.
- * <p/>
+ *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
@@ -20,6 +20,7 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.aggregator.microservices;
 
 /**
@@ -27,5 +28,5 @@ package com.iluwatar.aggregator.microservices;
  */
 public interface ProductInventoryClient {
 
-  int getProductInventories();
+  Integer getProductInventories();
 }

aggregator-microservices/aggregator-service/src/main/java/com/iluwatar/aggregator/microservices/ProductInventoryClientImpl.java

@@ -1,17 +1,17 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
- * <p/>
+ * Copyright © 2014-2019 Ilkka Seppälä
+ *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
  * in the Software without restriction, including without limitation the rights
  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  * copies of the Software, and to permit persons to whom the Software is
  * furnished to do so, subject to the following conditions:
- * <p/>
+ *
  * The above copyright notice and this permission notice shall be included in
  * all copies or substantial portions of the Software.
- * <p/>
+ *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
@@ -20,19 +20,18 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.aggregator.microservices;
 
-import org.apache.http.client.methods.CloseableHttpResponse;
-import org.apache.http.client.methods.HttpGet;
-import org.apache.http.impl.client.CloseableHttpClient;
-import org.apache.http.impl.client.HttpClients;
-import org.apache.http.util.EntityUtils;
+import java.io.IOException;
+import java.net.URI;
+import java.net.http.HttpClient;
+import java.net.http.HttpRequest;
+import java.net.http.HttpResponse;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.stereotype.Component;
 
-import java.io.IOException;
-
 /**
  * An adapter to communicate with inventory micro-service.
  */
@@ -42,16 +41,26 @@ public class ProductInventoryClientImpl implements ProductInventoryClient {
   private static final Logger LOGGER = LoggerFactory.getLogger(ProductInventoryClientImpl.class);
 
   @Override
-  public int getProductInventories() {
-    String response = "0";
-    try (CloseableHttpClient httpClient = HttpClients.createDefault()) {
-      HttpGet httpGet = new HttpGet("http://localhost:51516/inventories");
-      try (CloseableHttpResponse httpResponse = httpClient.execute(httpGet)) {
-        response = EntityUtils.toString(httpResponse.getEntity());
-      }
-    } catch (IOException e) {
-      LOGGER.error("Exception caught.", e);
+  public Integer getProductInventories() {
+    var response = "";
+
+    var request = HttpRequest.newBuilder()
+        .GET()
+        .uri(URI.create("http://localhost:51516/inventories"))
+        .build();
+    var client = HttpClient.newHttpClient();
+    try {
+      var httpResponse = client.send(request, HttpResponse.BodyHandlers.ofString());
+      response = httpResponse.body();
+    } catch (IOException ioe) {
+      LOGGER.error("IOException Occurred", ioe);
+    } catch (InterruptedException ie) {
+      LOGGER.error("InterruptedException Occurred", ie);
+    }
+    if ("".equalsIgnoreCase(response)) {
+      return null;
+    } else {
+      return Integer.parseInt(response);
     }
-    return Integer.parseInt(response);
   }
 }

aggregator-microservices/aggregator-service/src/main/resources/application.properties

@@ -1,6 +1,6 @@
 #
 # The MIT License
-# Copyright (c) 2014-2016 Ilkka Seppälä
+# Copyright © 2014-2019 Ilkka Seppälä
 #
 # Permission is hereby granted, free of charge, to any person obtaining a copy
 # of this software and associated documentation files (the "Software"), to deal
@@ -20,5 +20,4 @@
 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 # THE SOFTWARE.
 #
-
 server.port=50004

aggregator-microservices/aggregator-service/src/test/java/com/iluwatar/aggregator/microservices/AggregatorTest.java

@@ -1,17 +1,17 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
- * <p/>
+ * Copyright © 2014-2019 Ilkka Seppälä
+ *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
  * in the Software without restriction, including without limitation the rights
  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  * copies of the Software, and to permit persons to whom the Software is
  * furnished to do so, subject to the following conditions:
- * <p/>
+ *
  * The above copyright notice and this permission notice shall be included in
  * all copies or substantial portions of the Software.
- * <p/>
+ *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
@@ -20,17 +20,18 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.aggregator.microservices;
 
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.mockito.Mockito.when;
+
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
 import org.mockito.MockitoAnnotations;
 
-import static org.junit.jupiter.api.Assertions.assertEquals;
-import static org.mockito.Mockito.when;
-
 /**
  * Test Aggregation of domain objects
  */
@@ -55,13 +56,13 @@ public class AggregatorTest {
    */
   @Test
   public void testGetProduct() {
-    String title = "The Product Title.";
-    int inventories = 5;
+    var title = "The Product Title.";
+    var inventories = 5;
 
     when(informationClient.getProductTitle()).thenReturn(title);
     when(inventoryClient.getProductInventories()).thenReturn(inventories);
 
-    Product testProduct = aggregator.getProduct();
+    var testProduct = aggregator.getProduct();
 
     assertEquals(title, testProduct.getTitle());
     assertEquals(inventories, testProduct.getProductInventories());

aggregator-microservices/etc/aggregator-microservices.urm.puml

@@ -0,0 +1,2 @@
+@startuml
+@enduml

aggregator-microservices/information-microservice/etc/information-microservice.urm.puml

@@ -0,0 +1,12 @@
+@startuml
+package com.iluwatar.information.microservice {
+  class InformationApplication {
+    + InformationApplication()
+    + main(args : String[]) {static}
+  }
+  class InformationController {
+    + InformationController()
+    + getProductTitle() : String
+  }
+}
+@enduml

aggregator-microservices/information-microservice/pom.xml

@@ -1,84 +1,76 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<!--
-
-    The MIT License
-    Copyright (c) 2014-2016 Ilkka Seppälä
-
-    Permission is hereby granted, free of charge, to any person obtaining a copy
-    of this software and associated documentation files (the "Software"), to deal
-    in the Software without restriction, including without limitation the rights
-    to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-    copies of the Software, and to permit persons to whom the Software is
-    furnished to do so, subject to the following conditions:
-
-    The above copyright notice and this permission notice shall be included in
-    all copies or substantial portions of the Software.
-
-    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-    IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-    AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-    OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
-    THE SOFTWARE.
-
--->
+<!-- The MIT License Copyright © 2014-2019 Ilkka Seppälä Permission is hereby 
+	granted, free of charge, to any person obtaining a copy of this software 
+	and associated documentation files (the "Software"), to deal in the Software 
+	without restriction, including without limitation the rights to use, copy, 
+	modify, merge, publish, distribute, sublicense, and/or sell copies of the 
+	Software, and to permit persons to whom the Software is furnished to do so, 
+	subject to the following conditions: The above copyright notice and this 
+	permission notice shall be included in all copies or substantial portions 
+	of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY 
+	KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 
+	MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN 
+	NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, 
+	DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, 
+	ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER 
+	DEALINGS IN THE SOFTWARE. -->
 <project xmlns="http://maven.apache.org/POM/4.0.0"
-         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
-    <parent>
-        <artifactId>aggregator-microservices</artifactId>
-        <groupId>com.iluwatar</groupId>
-        <version>1.21.0-SNAPSHOT</version>
-    </parent>
-    <modelVersion>4.0.0</modelVersion>
+	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+	<parent>
+		<artifactId>aggregator-microservices</artifactId>
+		<groupId>com.iluwatar</groupId>
+		<version>1.23.0-SNAPSHOT</version>
+	</parent>
+	<modelVersion>4.0.0</modelVersion>
 
-    <artifactId>information-microservice</artifactId>
-    <packaging>jar</packaging>
+	<artifactId>information-microservice</artifactId>
+	<packaging>jar</packaging>
 
-    <dependencyManagement>
-        <dependencies>
-            <dependency>
-                <groupId>org.springframework.boot</groupId>
-                <artifactId>spring-boot-dependencies</artifactId>
-            </dependency>
-        </dependencies>
-    </dependencyManagement>
-    <dependencies>
-        <dependency>
-            <groupId>org.springframework</groupId>
-            <artifactId>spring-webmvc</artifactId>
-        </dependency>
-        <dependency>
-            <groupId>org.springframework.boot</groupId>
-            <artifactId>spring-boot-starter-web</artifactId>
-        </dependency>
-        <dependency>
-            <groupId>org.junit.jupiter</groupId>
-            <artifactId>junit-jupiter-api</artifactId>
-            <scope>test</scope>
-        </dependency>
-        <dependency>
-            <groupId>org.junit.jupiter</groupId>
-            <artifactId>junit-jupiter-engine</artifactId>
-            <scope>test</scope>
-        </dependency>
-    </dependencies>
+	<dependencies>
+		<dependency>
+			<groupId>org.springframework</groupId>
+			<artifactId>spring-webmvc</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-web</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>org.junit.jupiter</groupId>
+			<artifactId>junit-jupiter-engine</artifactId>
+			<scope>test</scope>
+		</dependency>
+	</dependencies>
 
-    <build>
-        <plugins>
-            <plugin>
-                <groupId>org.springframework.boot</groupId>
-                <artifactId>spring-boot-maven-plugin</artifactId>
-                <version>${spring-boot.version}</version>
-                <executions>
-                    <execution>
-                        <goals>
-                            <goal>repackage</goal>
-                        </goals>
-                    </execution>
-                </executions>
-            </plugin>
-        </plugins>
-    </build>
+	<build>
+		<plugins>
+			<plugin>
+				<groupId>org.springframework.boot</groupId>
+				<artifactId>spring-boot-maven-plugin</artifactId>
+				<executions>
+					<execution>
+						<goals>
+							<goal>repackage</goal>
+						</goals>
+					</execution>
+				</executions>
+			</plugin>
+			<plugin>
+				<groupId>org.apache.maven.plugins</groupId>
+				<artifactId>maven-assembly-plugin</artifactId>
+				<executions>
+					<execution>
+						<configuration>
+							<archive>
+								<manifest>
+									<mainClass>com.iluwatar.information.microservices.InformationApplication</mainClass>
+								</manifest>
+							</archive>
+						</configuration>
+					</execution>
+				</executions>
+			</plugin>
+		</plugins>
+	</build>
 </project>

aggregator-microservices/information-microservice/src/main/java/com/iluwatar/information/microservice/InformationApplication.java

@@ -1,17 +1,17 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
- * <p/>
+ * Copyright © 2014-2019 Ilkka Seppälä
+ *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
  * in the Software without restriction, including without limitation the rights
  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  * copies of the Software, and to permit persons to whom the Software is
  * furnished to do so, subject to the following conditions:
- * <p/>
+ *
  * The above copyright notice and this permission notice shall be included in
  * all copies or substantial portions of the Software.
- * <p/>
+ *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
@@ -20,6 +20,7 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.information.microservice;
 
 import org.springframework.boot.SpringApplication;

aggregator-microservices/information-microservice/src/main/java/com/iluwatar/information/microservice/InformationController.java

@@ -1,17 +1,17 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
- * <p/>
+ * Copyright © 2014-2019 Ilkka Seppälä
+ *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
  * in the Software without restriction, including without limitation the rights
  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  * copies of the Software, and to permit persons to whom the Software is
  * furnished to do so, subject to the following conditions:
- * <p/>
+ *
  * The above copyright notice and this permission notice shall be included in
  * all copies or substantial portions of the Software.
- * <p/>
+ *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
@@ -20,6 +20,7 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.information.microservice;
 
 import org.springframework.web.bind.annotation.RequestMapping;
@@ -27,7 +28,7 @@ import org.springframework.web.bind.annotation.RequestMethod;
 import org.springframework.web.bind.annotation.RestController;
 
 /**
- * Controller providing endpoints to retrieve information about products
+ * Controller providing endpoints to retrieve information about products.
  */
 @RestController
 public class InformationController {

aggregator-microservices/information-microservice/src/main/resources/application.properties

@@ -1,6 +1,6 @@
 #
 # The MIT License
-# Copyright (c) 2014-2016 Ilkka Seppälä
+# Copyright © 2014-2019 Ilkka Seppälä
 #
 # Permission is hereby granted, free of charge, to any person obtaining a copy
 # of this software and associated documentation files (the "Software"), to deal
@@ -20,5 +20,4 @@
 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 # THE SOFTWARE.
 #
-
 server.port=51515

aggregator-microservices/information-microservice/src/test/java/com/iluwatar/information/microservice/InformationControllerTest.java

@@ -1,17 +1,17 @@
-/**
+/*
  * The MIT License
- * Copyright (c) 2014-2016 Ilkka Seppälä
- * <p/>
+ * Copyright © 2014-2019 Ilkka Seppälä
+ *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
  * in the Software without restriction, including without limitation the rights
  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  * copies of the Software, and to permit persons to whom the Software is
  * furnished to do so, subject to the following conditions:
- * <p/>
+ *
  * The above copyright notice and this permission notice shall be included in
  * all copies or substantial portions of the Software.
- * <p/>
+ *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
@@ -20,12 +20,13 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+
 package com.iluwatar.information.microservice;
 
-import org.junit.jupiter.api.Test;
-
 import static org.junit.jupiter.api.Assertions.assertEquals;
 
+import org.junit.jupiter.api.Test;
+
 /**
  * Test for Information Rest Controller
  */
@@ -33,10 +34,8 @@ public class InformationControllerTest {
 
   @Test
   public void shouldGetProductTitle() {
-    InformationController infoController = new InformationController();
-
-    String title = infoController.getProductTitle();
-
+    var infoController = new InformationController();
+    var title = infoController.getProductTitle();
     assertEquals("The Product Title.", title);
   }
 

aggregator-microservices/inventory-microservice/etc/inventory-microservice.urm.puml

@@ -0,0 +1,12 @@
+@startuml
+package com.iluwatar.inventory.microservice {
+  class InventoryApplication {
+    + InventoryApplication()
+    + main(args : String[]) {static}
+  }
+  class InventoryController {
+    + InventoryController()
+    + getProductInventories() : int
+  }
+}
+@enduml

aggregator-microservices/inventory-microservice/pom.xml

@@ -1,84 +1,75 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<!--
-
-    The MIT License
-    Copyright (c) 2014-2016 Ilkka Seppälä
-
-    Permission is hereby granted, free of charge, to any person obtaining a copy
-    of this software and associated documentation files (the "Software"), to deal
-    in the Software without restriction, including without limitation the rights
-    to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-    copies of the Software, and to permit persons to whom the Software is
-    furnished to do so, subject to the following conditions:
-
-    The above copyright notice and this permission notice shall be included in
-    all copies or substantial portions of the Software.
-
-    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-    IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-    AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-    OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
-    THE SOFTWARE.
-
--->
+<!-- The MIT License Copyright © 2014-2019 Ilkka Seppälä Permission is hereby 
+	granted, free of charge, to any person obtaining a copy of this software 
+	and associated documentation files (the "Software"), to deal in the Software 
+	without restriction, including without limitation the rights to use, copy, 
+	modify, merge, publish, distribute, sublicense, and/or sell copies of the 
+	Software, and to permit persons to whom the Software is furnished to do so, 
+	subject to the following conditions: The above copyright notice and this 
+	permission notice shall be included in all copies or substantial portions 
+	of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY 
+	KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 
+	MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN 
+	NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, 
+	DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, 
+	ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER 
+	DEALINGS IN THE SOFTWARE. -->
 <project xmlns="http://maven.apache.org/POM/4.0.0"
-         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
-    <parent>
-        <artifactId>aggregator-microservices</artifactId>
-        <groupId>com.iluwatar</groupId>
-        <version>1.21.0-SNAPSHOT</version>
-    </parent>
-    <modelVersion>4.0.0</modelVersion>
+	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+	<parent>
+		<artifactId>aggregator-microservices</artifactId>
+		<groupId>com.iluwatar</groupId>
+		<version>1.23.0-SNAPSHOT</version>
+	</parent>
+	<modelVersion>4.0.0</modelVersion>
+	<artifactId>inventory-microservice</artifactId>
 
-    <artifactId>inventory-microservice</artifactId>
-    <packaging>jar</packaging>
+	<packaging>jar</packaging>
+	<dependencies>
+		<dependency>
+			<groupId>org.springframework</groupId>
+			<artifactId>spring-webmvc</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-web</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>org.junit.jupiter</groupId>
+			<artifactId>junit-jupiter-engine</artifactId>
+			<scope>test</scope>
+		</dependency>
+	</dependencies>
 
-    <dependencyManagement>
-        <dependencies>
-            <dependency>
-                <groupId>org.springframework.boot</groupId>
-                <artifactId>spring-boot-dependencies</artifactId>
-            </dependency>
-        </dependencies>
-    </dependencyManagement>
-    <dependencies>
-        <dependency>
-            <groupId>org.springframework</groupId>
-            <artifactId>spring-webmvc</artifactId>
-        </dependency>
-        <dependency>
-            <groupId>org.springframework.boot</groupId>
-            <artifactId>spring-boot-starter-web</artifactId>
-        </dependency>
-        <dependency>
-            <groupId>org.junit.jupiter</groupId>
-            <artifactId>junit-jupiter-api</artifactId>
-            <scope>test</scope>
-        </dependency>
-        <dependency>
-            <groupId>org.junit.jupiter</groupId>
-            <artifactId>junit-jupiter-engine</artifactId>
-            <scope>test</scope>
-        </dependency>
-    </dependencies>
-
-    <build>
-        <plugins>
-            <plugin>
-                <groupId>org.springframework.boot</groupId>
-                <artifactId>spring-boot-maven-plugin</artifactId>
-                <version>${spring-boot.version}</version>
-                <executions>
-                    <execution>
-                        <goals>
-                            <goal>repackage</goal>
-                        </goals>
-                    </execution>
-                </executions>
-            </plugin>
-        </plugins>
-    </build>
-</project>
+	<build>
+		<plugins>
+			<plugin>
+				<groupId>org.springframework.boot</groupId>
+				<artifactId>spring-boot-maven-plugin</artifactId>
+				<executions>
+					<execution>
+						<goals>
+							<goal>repackage</goal>
+						</goals>
+					</execution>
+				</executions>
+			</plugin>
+			<plugin>
+				<groupId>org.apache.maven.plugins</groupId>
+				<artifactId>maven-assembly-plugin</artifactId>
+				<executions>
+					<execution>
+						<configuration>
+							<archive>
+								<manifest>
+									<mainClass>com.iluwatar.inventory.microservices.InventoryApplication</mainClass>
+								</manifest>
+							</archive>
+						</configuration>
+					</execution>
+				</executions>
+			</plugin>
+		</plugins>
+	</build>
+</project>