format readme.md

* #455 work on readme.md

* #455 work on readme.md

* #455 S3 web site complete

* #455 add cloudfront and diagram

* Apply suggestions from code review

added syntax highlighting

Co-authored-by: Subhrodip Mohanta <hello@subho.xyz>

.all-contributorsrc

@@ -315,7 +315,8 @@
       "avatar_url": "https://avatars1.githubusercontent.com/u/6295975?v=4",
       "profile": "https://github.com/Anurag870",
       "contributions": [
-        "code"
+        "code",
+        "doc"
       ]
     },
     {
@@ -946,7 +947,8 @@
       "avatar_url": "https://avatars3.githubusercontent.com/u/23739158?v=4",
       "profile": "https://github.com/grzesiekkedzior",
       "contributions": [
-        "code"
+        "code",
+        "review"
       ]
     },
     {
@@ -1075,6 +1077,333 @@
       "contributions": [
         "code"
       ]
+    },
+    {
+      "login": "ravening",
+      "name": "Rakesh",
+      "avatar_url": "https://avatars1.githubusercontent.com/u/10645273?v=4",
+      "profile": "https://github.com/ravening",
+      "contributions": [
+        "code",
+        "review"
+      ]
+    },
+    {
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+      "name": "Wei Seng",
+      "avatar_url": "https://avatars0.githubusercontent.com/u/8037883?v=4",
+      "profile": "https://github.com/vINCENT8888801",
+      "contributions": [
+        "code"
+      ]
+    },
+    {
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+      "name": "Ashish Trivedi",
+      "avatar_url": "https://avatars3.githubusercontent.com/u/23194128?v=4",
+      "profile": "https://www.linkedin.com/in/ashish-trivedi-218379135/",
+      "contributions": [
+        "code"
+      ]
+    },
+    {
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+      "name": "洪月阳",
+      "avatar_url": "https://avatars1.githubusercontent.com/u/41055099?v=4",
+      "profile": "https://rayyounghong.com",
+      "contributions": [
+        "code"
+      ]
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+      "avatar_url": "https://avatars0.githubusercontent.com/u/47092464?v=4",
+      "profile": "https://xdvrx1.github.io/",
+      "contributions": [
+        "review",
+        "ideas"
+      ]
+    },
+    {
+      "login": "ohbus",
+      "name": "Subhrodip Mohanta",
+      "avatar_url": "https://avatars0.githubusercontent.com/u/13291222?v=4",
+      "profile": "http://subho.xyz",
+      "contributions": [
+        "code",
+        "review"
+      ]
+    },
+    {
+      "login": "nahteb",
+      "name": "Bethan Palmer",
+      "avatar_url": "https://avatars3.githubusercontent.com/u/13121570?v=4",
+      "profile": "https://github.com/nahteb",
+      "contributions": [
+        "code"
+      ]
+    },
+    {
+      "login": "ToxicDreamz",
+      "name": "Toxic Dreamz",
+      "avatar_url": "https://avatars0.githubusercontent.com/u/45225562?v=4",
+      "profile": "https://github.com/ToxicDreamz",
+      "contributions": [
+        "code"
+      ]
+    },
+    {
+      "login": "edycutjong",
+      "name": "Edy Cu Tjong",
+      "avatar_url": "https://avatars1.githubusercontent.com/u/1098102?v=4",
+      "profile": "http://www.edycutjong.com",
+      "contributions": [
+        "doc"
+      ]
+    },
+    {
+      "login": "mkrzywanski",
+      "name": "Michał Krzywański",
+      "avatar_url": "https://avatars0.githubusercontent.com/u/15279585?v=4",
+      "profile": "https://github.com/mkrzywanski",
+      "contributions": [
+        "code"
+      ]
+    },
+    {
+      "login": "stefanbirkner",
+      "name": "Stefan Birkner",
+      "avatar_url": "https://avatars1.githubusercontent.com/u/711349?v=4",
+      "profile": "https://www.stefan-birkner.de",
+      "contributions": [
+        "code"
+      ]
+    },
+    {
+      "login": "fedorskvorcov",
+      "name": "Fedor Skvorcov",
+      "avatar_url": "https://avatars3.githubusercontent.com/u/43882212?v=4",
+      "profile": "https://github.com/fedorskvorcov",
+      "contributions": [
+        "code"
+      ]
+    },
+    {
+      "login": "samilAyoub",
+      "name": "samilAyoub",
+      "avatar_url": "https://avatars0.githubusercontent.com/u/61546990?v=4",
+      "profile": "https://github.com/samilAyoub",
+      "contributions": [
+        "code"
+      ]
+    },
+    {
+      "login": "vdlald",
+      "name": "Vladislav Golubinov",
+      "avatar_url": "https://avatars0.githubusercontent.com/u/29997701?v=4",
+      "profile": "https://github.com/vdlald",
+      "contributions": [
+        "code"
+      ]
+    },
+    {
+      "login": "swarajsaaj",
+      "name": "Swaraj",
+      "avatar_url": "https://avatars2.githubusercontent.com/u/6285049?v=4",
+      "profile": "https://github.com/swarajsaaj",
+      "contributions": [
+        "code"
+      ]
+    },
+    {
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+      "name": "Christoph Flick",
+      "avatar_url": "https://avatars0.githubusercontent.com/u/4465376?v=4",
+      "profile": "http://christophflick.de",
+      "contributions": [
+        "doc"
+      ]
+    },
+    {
+      "login": "Ascenio",
+      "name": "Ascênio",
+      "avatar_url": "https://avatars1.githubusercontent.com/u/7662016?v=4",
+      "profile": "https://github.com/Ascenio",
+      "contributions": [
+        "review"
+      ]
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+    {
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+      "name": "Domenico Sibilio",
+      "avatar_url": "https://avatars2.githubusercontent.com/u/24280982?v=4",
+      "profile": "https://www.linkedin.com/in/domenico-sibilio/",
+      "contributions": [
+        "doc"
+      ]
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+      "name": "Akash Chandwani",
+      "avatar_url": "https://avatars2.githubusercontent.com/u/3483277?v=4",
+      "profile": "https://github.com/akashchandwani",
+      "contributions": [
+        "review"
+      ]
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+      "profile": "http://www.linkedin.com/in/manannikov",
+      "contributions": [
+        "code"
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+      "name": "Eiman",
+      "avatar_url": "https://avatars0.githubusercontent.com/u/20307301?v=4",
+      "profile": "https://github.com/eimanip",
+      "contributions": [
+        "code"
+      ]
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+      "avatar_url": "https://avatars0.githubusercontent.com/u/42976136?v=4",
+      "profile": "https://github.com/OrangePants-R",
+      "contributions": [
+        "doc"
+      ]
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+    {
+      "login": "ibrahimAlii",
+      "name": "Ibrahim ali abdelghany",
+      "avatar_url": "https://avatars2.githubusercontent.com/u/21141301?v=4",
+      "profile": "https://ibrahimalii.github.io/",
+      "contributions": [
+        "review"
+      ]
+    },
+    {
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+      "name": "Girish Kulkarni",
+      "avatar_url": "https://avatars3.githubusercontent.com/u/5161548?v=4",
+      "profile": "https://github.com/gkulkarni2020",
+      "contributions": [
+        "doc"
+      ]
+    },
+    {
+      "login": "omk13",
+      "name": "Omar Karazoun",
+      "avatar_url": "https://avatars0.githubusercontent.com/u/59054172?v=4",
+      "profile": "https://github.com/omk13",
+      "contributions": [
+        "code"
+      ]
+    },
+    {
+      "login": "jeff303",
+      "name": "Jeff Evans",
+      "avatar_url": "https://avatars0.githubusercontent.com/u/3521562?v=4",
+      "profile": "https://github.com/jeff303",
+      "contributions": [
+        "code"
+      ]
+    },
+    {
+      "login": "viveksb007",
+      "name": "Vivek Singh",
+      "avatar_url": "https://avatars1.githubusercontent.com/u/12713808?v=4",
+      "profile": "https://viveksb007.github.io",
+      "contributions": [
+        "code"
+      ]
+    },
+    {
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+      "name": "siavash",
+      "avatar_url": "https://avatars2.githubusercontent.com/u/18074419?v=4",
+      "profile": "https://github.com/siavashsoleymani",
+      "contributions": [
+        "code"
+      ]
+    },
+    {
+      "login": "ruchpeanuts",
+      "name": "ruchpeanuts",
+      "avatar_url": "https://avatars0.githubusercontent.com/u/29301900?v=4",
+      "profile": "https://github.com/ruchpeanuts",
+      "contributions": [
+        "doc"
+      ]
+    },
+    {
+      "login": "warp125",
+      "name": "warp125",
+      "avatar_url": "https://avatars1.githubusercontent.com/u/48073115?v=4",
+      "profile": "https://github.com/warp125",
+      "contributions": [
+        "translation"
+      ]
+    },
+    {
+      "login": "tkhadir",
+      "name": "KHADIR Tayeb",
+      "avatar_url": "https://avatars1.githubusercontent.com/u/45130488?v=4",
+      "profile": "http://libkhadir.fr",
+      "contributions": [
+        "translation"
+      ]
+    },
+    {
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+      "name": "ignite1771",
+      "avatar_url": "https://avatars2.githubusercontent.com/u/59446563?v=4",
+      "profile": "https://github.com/ignite1771",
+      "contributions": [
+        "code"
+      ]
+    },
+    {
+      "login": "demirhalil",
+      "name": "Halil Demir",
+      "avatar_url": "https://avatars1.githubusercontent.com/u/22895118?v=4",
+      "profile": "https://github.com/demirhalil",
+      "contributions": [
+        "translation"
+      ]
+    },
+    {
+      "login": "rohit10000",
+      "name": "Rohit Singh",
+      "avatar_url": "https://avatars.githubusercontent.com/u/20845565?v=4",
+      "profile": "https://github.com/rohit10000",
+      "contributions": [
+        "code"
+      ]
+    },
+    {
+      "login": "byoungju94",
+      "name": "byoungju94",
+      "avatar_url": "https://avatars.githubusercontent.com/u/42516378?v=4",
+      "profile": "https://github.com/byoungju94",
+      "contributions": [
+        "code"
+      ]
+    },
+    {
+      "login": "moustafafarhat",
+      "name": "Moustafa Farhat",
+      "avatar_url": "https://avatars.githubusercontent.com/u/38836727?v=4",
+      "profile": "https://github.com/moustafafarhat",
+      "contributions": [
+        "translation"
+      ]
     }
   ],
   "contributorsPerLine": 4,

.github/workflows/maven-ci.yml

@@ -0,0 +1,80 @@
+#
+# The MIT License
+# Copyright © 2014-2021 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
+
+on:
+  push:
+    branches: [ master ]
+
+
+jobs:
+
+  build:
+
+    runs-on: ubuntu-20.04
+
+    steps:
+
+    - name: Checkout Code
+      uses: actions/checkout@v2
+      with:
+        # Disabling shallow clone for improving relevancy of SonarQube reporting
+        fetch-depth: 0
+
+    - name: Set up JDK 11
+      uses: actions/setup-java@v1
+      with:
+        java-version: 11
+
+    - name: Cache SonarCloud packages
+      uses: actions/cache@v2
+      with:
+        path: ~/.sonar/cache
+        key: ${{ runner.os }}-sonar
+        restore-keys: ${{ runner.os }}-sonar
+
+    - name: Cache Maven dependencies
+      uses: actions/cache@v2
+      with:
+        path: ~/.m2/repository
+        key: ${{ runner.os }}-maven-${{ hashFiles('**/pom.xml') }}
+        restore-keys: |
+          ${{ runner.os }}-maven-
+
+    # Some tests need screen access
+    - name: Install xvfb
+      run: sudo apt-get install -y xvfb
+
+    # The SonarQube analysis is only for the master branch of the main repository.
+    # SonarQube scan does not work for forked repositories try changing it to xvfb-run mvn clean verify
+    # See https://jira.sonarsource.com/browse/MMF-1371
+    - name: Build with Maven and run SonarQube analysis
+      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.GITHUB_TOKEN }}
+        SONAR_TOKEN: ${{ secrets.SONAR_TOKEN }}

.github/workflows/maven-pr-builder.yml

@@ -1,6 +1,6 @@
 #
 # The MIT License
-# Copyright © 2014-2019 Ilkka Seppälä
+# Copyright © 2014-2021 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
@@ -24,37 +24,41 @@
 # 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
+name: Java PR Builder
 
 on:
-  push:
-    branches: [ master ]
   pull_request:
     branches: [ master ]
+    types: [ opened, reopened, synchronize, labeled, unlabeled ]
 
 jobs:
   build:
 
-    runs-on: ubuntu-18.04
+    runs-on: ubuntu-20.04
 
     steps:
-    - uses: actions/checkout@v2
+    - name: Checkout Code
+      uses: actions/checkout@v2
+    
     - name: Set up JDK 11
       uses: actions/setup-java@v1
       with:
         java-version: 11
+    
+    - name: Cache Maven Dependecies
+      uses: actions/cache@v2
+      with:
+        path: ~/.m2/repository
+        key: ${{ runner.os }}-maven-${{ hashFiles('**/pom.xml') }}
+        restore-keys: |
+          ${{ runner.os }}-maven-
+    
     # Some tests need screen access
     - name: Install xvfb
-      run: sudo apt-get install xvfb
-    # SonarQube scan does not work for forked repositories
+      run: sudo apt-get install -y xvfb
+    
+    # This worflow is only for building Pull Requests, the master branch runs Sonar analysis on the main repository.
+    # 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

@@ -1,19 +1,54 @@
+################## Eclipse ######################
 target
 .metadata
 .settings
 .classpath
 .project
 *.class
-# Package Files #
+tmp/
+*.tmp
+*.bak
+*~.nib
+local.properties
+.loadpath
+.recommenders
+
+#######  Java annotation processor (APT) ########
+.factorypath
+
+################ Package Files ##################
 *.jar
 *.war
 *.ear
-.idea
-*.iml
 *.swp
 datanucleus.log
 /bin/
-/bin/
-/bin/
 *.log
 event-sourcing/Journal.json
+
+################## Checkstyle ###################
+.checkstyle
+
+##################### STS #######################
+.apt_generated
+.springBeans
+.sts4-cache
+
+################# IntelliJ IDEA #################
+.idea
+*.iws
+*.iml
+*.ipr
+
+################### NetBeans ####################
+/nbproject/private/
+/nbbuild/
+/dist/
+/nbdist/
+/.nb-gradle/
+build/
+!**/src/main/**/build/
+!**/src/test/**/build/
+
+#################### VS Code ####################
+.vscode/

LICENSE.md

@@ -1,6 +1,6 @@
 The MIT License (MIT)
 
-Copyright (c) 2014-2020 Ilkka Seppälä
+Copyright (c) 2014-2021 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

@@ -6,12 +6,19 @@
 
 ![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)
+[![Lines of Code](https://sonarcloud.io/api/project_badges/measure?project=iluwatar_java-design-patterns&metric=ncloc)](https://sonarcloud.io/dashboard?id=iluwatar_java-design-patterns) 
+[![Coverage](https://sonarcloud.io/api/project_badges/measure?project=iluwatar_java-design-patterns&metric=coverage)](https://sonarcloud.io/dashboard?id=iluwatar_java-design-patterns)
 [![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)
-[![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-118-orange.svg?style=flat-square)](#contributors-)
+[![All Contributors](https://img.shields.io/badge/all_contributors-154-orange.svg?style=flat-square)](#contributors-)
 <!-- ALL-CONTRIBUTORS-BADGE:END -->
 
+<br/>
+
+Read in different language : [![CN](/assets/flags/CN.png)**CN**](/zh/README.md),[![KR](/assets/flags/KR.png)**KR**](/ko/README.md),[![FR](/assets/flags/FR.png)**FR**](/fr/README.md),[![TR](/assets/flags/TR.png)**TR**](/tr/README.md),[![AR](/assets/flags/AR.png)**AR**](/ar/README.md),
+
+<br/>
+
 # Introduction
 
 Design patterns are the best formalized practices a programmer can use to
@@ -30,7 +37,7 @@ 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
+programming tutorials on 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
@@ -69,186 +76,240 @@ This project is licensed under the terms of the MIT license.
 <!-- 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>
+    <td align="center"><a href="https://github.com/iluwatar"><img src="https://avatars1.githubusercontent.com/u/582346?v=4?s=100" 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?s=100" 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?s=100" 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?s=100" 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>
+    <td align="center"><a href="http://www.joemccarthy.co.uk"><img src="https://avatars0.githubusercontent.com/u/4526195?v=4?s=100" 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?s=100" 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?s=100" 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?s=100" 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>
+    <td align="center"><a href="https://twitter.com/i_sabiq"><img src="https://avatars1.githubusercontent.com/u/19510920?v=4?s=100" 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?s=100" 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?s=100" 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?s=100" 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>
+    <td align="center"><a href="https://github.com/Crossy147"><img src="https://avatars2.githubusercontent.com/u/7272996?v=4?s=100" 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?s=100" 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?s=100" 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?s=100" 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>
+    <td align="center"><a href="https://github.com/TylerMcConville"><img src="https://avatars0.githubusercontent.com/u/4946449?v=4?s=100" 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?s=100" 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?s=100" 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?s=100" 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>
+    <td align="center"><a href="https://github.com/ruslanpa"><img src="https://avatars2.githubusercontent.com/u/1503411?v=4?s=100" 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?s=100" 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?s=100" 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?s=100" 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>
+    <td align="center"><a href="https://github.com/4lexis"><img src="https://avatars0.githubusercontent.com/u/19871727?v=4?s=100" 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?s=100" 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?s=100" 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?s=100" 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>
+    <td align="center"><a href="https://github.com/gvsharma"><img src="https://avatars1.githubusercontent.com/u/6648152?v=4?s=100" 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?s=100" 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?s=100" 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?s=100" 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>
+    <td align="center"><a href="https://amarnath510.github.io/portfolio"><img src="https://avatars0.githubusercontent.com/u/4599623?v=4?s=100" 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?s=100" 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> <a href="https://github.com/iluwatar/java-design-patterns/commits?author=Anurag870" title="Documentation">📖</a></td>
+    <td align="center"><a href="http://theerroris.me"><img src="https://avatars0.githubusercontent.com/u/1685953?v=4?s=100" 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?s=100" 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>
+    <td align="center"><a href="https://github.com/MaVdbussche"><img src="https://avatars1.githubusercontent.com/u/26136934?v=4?s=100" 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?s=100" 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?s=100" 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?s=100" 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>
+    <td align="center"><a href="http://ccygnus.com/"><img src="https://avatars1.githubusercontent.com/u/9342724?v=4?s=100" 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?s=100" 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?s=100" 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?s=100" 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>
+    <td align="center"><a href="https://github.com/lbroman"><img src="https://avatars1.githubusercontent.com/u/86007?v=4?s=100" 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?s=100" 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?s=100" 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?s=100" 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>
+    <td align="center"><a href="https://github.com/staillebois"><img src="https://avatars0.githubusercontent.com/u/23701200?v=4?s=100" 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?s=100" 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?s=100" 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?s=100" 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>
+    <td align="center"><a href="https://github.com/7agustibm"><img src="https://avatars0.githubusercontent.com/u/8149332?v=4?s=100" 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?s=100" 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?s=100" 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?s=100" 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>
+    <td align="center"><a href="http://adamski.pro"><img src="https://avatars1.githubusercontent.com/u/6537430?v=4?s=100" 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?s=100" 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?s=100" 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?s=100" 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>
+    <td align="center"><a href="https://github.com/fanofxiaofeng"><img src="https://avatars0.githubusercontent.com/u/3983683?v=4?s=100" 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?s=100" 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?s=100" 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?s=100" 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>
+    <td align="center"><a href="https://github.com/kirill-vlasov"><img src="https://avatars3.githubusercontent.com/u/16112495?v=4?s=100" 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?s=100" 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?s=100" 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?s=100" 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>
+    <td align="center"><a href="https://github.com/MSaifAsif"><img src="https://avatars1.githubusercontent.com/u/6280554?v=4?s=100" 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?s=100" 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?s=100" 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?s=100" 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>
+    <td align="center"><a href="https://github.com/waisuan"><img src="https://avatars2.githubusercontent.com/u/10975700?v=4?s=100" 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?s=100" 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?s=100" 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?s=100" 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>
+    <td align="center"><a href="https://bitbucket.org/hannespernpeintner/"><img src="https://avatars3.githubusercontent.com/u/1679437?v=4?s=100" 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?s=100" 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?s=100" 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?s=100" 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> <a href="#design-hbothra15" title="Design">🎨</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>
+    <td align="center"><a href="https://github.com/giorgosmav21"><img src="https://avatars2.githubusercontent.com/u/22855493?v=4?s=100" 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?s=100" 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> <a href="#design-hbothra15" title="Design">🎨</a></td>
+    <td align="center"><a href="https://www.kevinpeters.net/about/"><img src="https://avatars1.githubusercontent.com/u/12736734?v=4?s=100" 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?s=100" 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>
+    <td align="center"><a href="https://github.com/mookkiah"><img src="https://avatars1.githubusercontent.com/u/8975264?v=4?s=100" 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?s=100" 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?s=100" 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?s=100" 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>
+    <td align="center"><a href="https://www.linkedin.com/in/gopinathlangote/"><img src="https://avatars2.githubusercontent.com/u/10210778?v=4?s=100" 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?s=100" 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?s=100" 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?s=100" 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>
+    <td align="center"><a href="https://t.me/paul_docker"><img src="https://avatars1.githubusercontent.com/u/2404785?v=4?s=100" 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?s=100" 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?s=100" 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?s=100" 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>
+    <td align="center"><a href="https://github.com/ankurkaushal"><img src="https://avatars2.githubusercontent.com/u/2236616?v=4?s=100" 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?s=100" 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?s=100" 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?s=100" 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>
+    <td align="center"><a href="http://vk.com/yuri.orlov"><img src="https://avatars0.githubusercontent.com/u/1595733?v=4?s=100" 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?s=100" 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?s=100" 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?s=100" 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> <a href="https://github.com/iluwatar/java-design-patterns/pulls?q=is%3Apr+reviewed-by%3Agrzesiekkedzior" title="Reviewed Pull Requests">👀</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>
+    <td align="center"><a href="https://github.com/sivasubramanim"><img src="https://avatars2.githubusercontent.com/u/51107434?v=4?s=100" 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?s=100" 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?s=100" 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?s=100" 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>
-    <td align="center"><a href="https://zd-zero.github.io"><img src="https://avatars0.githubusercontent.com/u/21978370?v=4" width="100px;" alt=""/><br /><sub><b>Zaerald Denze Lungos</b></sub></a><br /><a href="#content-zd-zero" title="Content">🖋</a></td>
+    <td align="center"><a href="https://jahhein.github.io"><img src="https://avatars2.githubusercontent.com/u/10779515?v=4?s=100" 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?s=100" 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?s=100" width="100px;" alt=""/><br /><sub><b>Rachel M. Carmena</b></sub></a><br /><a href="#content-rachelcarmena" title="Content">🖋</a></td>
+    <td align="center"><a href="https://zd-zero.github.io"><img src="https://avatars0.githubusercontent.com/u/21978370?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Zaerald Denze Lungos</b></sub></a><br /><a href="#content-zd-zero" title="Content">🖋</a></td>
   </tr>
   <tr>
-    <td align="center"><a href="https://webpro.nl"><img src="https://avatars1.githubusercontent.com/u/456426?v=4" width="100px;" alt=""/><br /><sub><b>Lars Kappert</b></sub></a><br /><a href="#content-webpro" title="Content">🖋</a></td>
-    <td align="center"><a href="https://xiaod.info"><img src="https://avatars2.githubusercontent.com/u/21277644?v=4" width="100px;" alt=""/><br /><sub><b>Mike Liu</b></sub></a><br /><a href="#translation-xiaod-dev" title="Translation">🌍</a></td>
-    <td align="center"><a href="https://github.com/charlesfinley"><img src="https://avatars1.githubusercontent.com/u/6307904?v=4" width="100px;" alt=""/><br /><sub><b>Matt Dolan</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=charlesfinley" title="Code">💻</a></td>
-    <td align="center"><a href="https://github.com/MananS77"><img src="https://avatars3.githubusercontent.com/u/21033516?v=4" width="100px;" alt=""/><br /><sub><b>Manan</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/pulls?q=is%3Apr+reviewed-by%3AMananS77" title="Reviewed Pull Requests">👀</a></td>
+    <td align="center"><a href="https://webpro.nl"><img src="https://avatars1.githubusercontent.com/u/456426?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Lars Kappert</b></sub></a><br /><a href="#content-webpro" title="Content">🖋</a></td>
+    <td align="center"><a href="https://xiaod.info"><img src="https://avatars2.githubusercontent.com/u/21277644?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Mike Liu</b></sub></a><br /><a href="#translation-xiaod-dev" title="Translation">🌍</a></td>
+    <td align="center"><a href="https://github.com/charlesfinley"><img src="https://avatars1.githubusercontent.com/u/6307904?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Matt Dolan</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=charlesfinley" title="Code">💻</a> <a href="https://github.com/iluwatar/java-design-patterns/pulls?q=is%3Apr+reviewed-by%3Acharlesfinley" title="Reviewed Pull Requests">👀</a></td>
+    <td align="center"><a href="https://github.com/MananS77"><img src="https://avatars3.githubusercontent.com/u/21033516?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Manan</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/pulls?q=is%3Apr+reviewed-by%3AMananS77" title="Reviewed Pull Requests">👀</a></td>
   </tr>
   <tr>
-    <td align="center"><a href="https://github.com/nishant"><img src="https://avatars2.githubusercontent.com/u/15331971?v=4" width="100px;" alt=""/><br /><sub><b>Nishant Arora</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=nishant" title="Code">💻</a></td>
-    <td align="center"><a href="https://github.com/raja-peeyush-kumar-singh"><img src="https://avatars0.githubusercontent.com/u/5496024?v=4" width="100px;" alt=""/><br /><sub><b>Peeyush</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=raja-peeyush-kumar-singh" title="Code">💻</a></td>
-    <td align="center"><a href="https://github.com/charlesfinley"><img src="https://avatars1.githubusercontent.com/u/6307904?v=4" width="100px;" alt=""/><br /><sub><b>Matt Dolan</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=charlesfinley" title="Code">💻</a> <a href="https://github.com/iluwatar/java-design-patterns/pulls?q=is%3Apr+reviewed-by%3Acharlesfinley" title="Reviewed Pull Requests">👀</a></td>
+    <td align="center"><a href="https://github.com/nishant"><img src="https://avatars2.githubusercontent.com/u/15331971?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Nishant Arora</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=nishant" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/raja-peeyush-kumar-singh"><img src="https://avatars0.githubusercontent.com/u/5496024?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Peeyush</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=raja-peeyush-kumar-singh" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/ravening"><img src="https://avatars1.githubusercontent.com/u/10645273?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Rakesh</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=ravening" title="Code">💻</a> <a href="https://github.com/iluwatar/java-design-patterns/pulls?q=is%3Apr+reviewed-by%3Aravening" title="Reviewed Pull Requests">👀</a></td>
+    <td align="center"><a href="https://github.com/vINCENT8888801"><img src="https://avatars0.githubusercontent.com/u/8037883?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Wei Seng</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=vINCENT8888801" title="Code">💻</a></td>
+  </tr>
+  <tr>
+    <td align="center"><a href="https://www.linkedin.com/in/ashish-trivedi-218379135/"><img src="https://avatars3.githubusercontent.com/u/23194128?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Ashish Trivedi</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=ashishtrivedi16" title="Code">💻</a></td>
+    <td align="center"><a href="https://rayyounghong.com"><img src="https://avatars1.githubusercontent.com/u/41055099?v=4?s=100" width="100px;" alt=""/><br /><sub><b>洪月阳</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=RayYH" title="Code">💻</a></td>
+    <td align="center"><a href="https://xdvrx1.github.io/"><img src="https://avatars0.githubusercontent.com/u/47092464?v=4?s=100" width="100px;" alt=""/><br /><sub><b>xdvrx1</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/pulls?q=is%3Apr+reviewed-by%3Axdvrx1" title="Reviewed Pull Requests">👀</a> <a href="#ideas-xdvrx1" title="Ideas, Planning, & Feedback">🤔</a></td>
+    <td align="center"><a href="http://subho.xyz"><img src="https://avatars0.githubusercontent.com/u/13291222?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Subhrodip Mohanta</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=ohbus" title="Code">💻</a> <a href="https://github.com/iluwatar/java-design-patterns/pulls?q=is%3Apr+reviewed-by%3Aohbus" title="Reviewed Pull Requests">👀</a></td>
+  </tr>
+  <tr>
+    <td align="center"><a href="https://github.com/nahteb"><img src="https://avatars3.githubusercontent.com/u/13121570?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Bethan Palmer</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=nahteb" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/ToxicDreamz"><img src="https://avatars0.githubusercontent.com/u/45225562?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Toxic Dreamz</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=ToxicDreamz" title="Code">💻</a></td>
+    <td align="center"><a href="http://www.edycutjong.com"><img src="https://avatars1.githubusercontent.com/u/1098102?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Edy Cu Tjong</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=edycutjong" title="Documentation">📖</a></td>
+    <td align="center"><a href="https://github.com/mkrzywanski"><img src="https://avatars0.githubusercontent.com/u/15279585?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Michał Krzywański</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=mkrzywanski" title="Code">💻</a></td>
+  </tr>
+  <tr>
+    <td align="center"><a href="https://www.stefan-birkner.de"><img src="https://avatars1.githubusercontent.com/u/711349?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Stefan Birkner</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=stefanbirkner" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/fedorskvorcov"><img src="https://avatars3.githubusercontent.com/u/43882212?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Fedor Skvorcov</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=fedorskvorcov" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/samilAyoub"><img src="https://avatars0.githubusercontent.com/u/61546990?v=4?s=100" width="100px;" alt=""/><br /><sub><b>samilAyoub</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=samilAyoub" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/vdlald"><img src="https://avatars0.githubusercontent.com/u/29997701?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Vladislav Golubinov</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=vdlald" title="Code">💻</a></td>
+  </tr>
+  <tr>
+    <td align="center"><a href="https://github.com/swarajsaaj"><img src="https://avatars2.githubusercontent.com/u/6285049?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Swaraj</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=swarajsaaj" title="Code">💻</a></td>
+    <td align="center"><a href="http://christophflick.de"><img src="https://avatars0.githubusercontent.com/u/4465376?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Christoph Flick</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=ChFlick" title="Documentation">📖</a></td>
+    <td align="center"><a href="https://github.com/Ascenio"><img src="https://avatars1.githubusercontent.com/u/7662016?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Ascênio</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/pulls?q=is%3Apr+reviewed-by%3AAscenio" title="Reviewed Pull Requests">👀</a></td>
+    <td align="center"><a href="https://www.linkedin.com/in/domenico-sibilio/"><img src="https://avatars2.githubusercontent.com/u/24280982?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Domenico Sibilio</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=dsibilio" title="Documentation">📖</a></td>
+  </tr>
+  <tr>
+    <td align="center"><a href="https://github.com/akashchandwani"><img src="https://avatars2.githubusercontent.com/u/3483277?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Akash Chandwani</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/pulls?q=is%3Apr+reviewed-by%3Aakashchandwani" title="Reviewed Pull Requests">👀</a></td>
+    <td align="center"><a href="http://www.linkedin.com/in/manannikov"><img src="https://avatars2.githubusercontent.com/u/7019769?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Pavlo Manannikov</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=manannikov" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/eimanip"><img src="https://avatars0.githubusercontent.com/u/20307301?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Eiman</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=eimanip" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/OrangePants-R"><img src="https://avatars0.githubusercontent.com/u/42976136?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Rocky</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=OrangePants-R" title="Documentation">📖</a></td>
+  </tr>
+  <tr>
+    <td align="center"><a href="https://ibrahimalii.github.io/"><img src="https://avatars2.githubusercontent.com/u/21141301?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Ibrahim ali abdelghany</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/pulls?q=is%3Apr+reviewed-by%3AibrahimAlii" title="Reviewed Pull Requests">👀</a></td>
+    <td align="center"><a href="https://github.com/gkulkarni2020"><img src="https://avatars3.githubusercontent.com/u/5161548?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Girish Kulkarni</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=gkulkarni2020" title="Documentation">📖</a></td>
+    <td align="center"><a href="https://github.com/omk13"><img src="https://avatars0.githubusercontent.com/u/59054172?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Omar Karazoun</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=omk13" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/jeff303"><img src="https://avatars0.githubusercontent.com/u/3521562?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Jeff Evans</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=jeff303" title="Code">💻</a></td>
+  </tr>
+  <tr>
+    <td align="center"><a href="https://viveksb007.github.io"><img src="https://avatars1.githubusercontent.com/u/12713808?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Vivek Singh</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=viveksb007" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/siavashsoleymani"><img src="https://avatars2.githubusercontent.com/u/18074419?v=4?s=100" width="100px;" alt=""/><br /><sub><b>siavash</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=siavashsoleymani" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/ruchpeanuts"><img src="https://avatars0.githubusercontent.com/u/29301900?v=4?s=100" width="100px;" alt=""/><br /><sub><b>ruchpeanuts</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=ruchpeanuts" title="Documentation">📖</a></td>
+    <td align="center"><a href="https://github.com/warp125"><img src="https://avatars1.githubusercontent.com/u/48073115?v=4?s=100" width="100px;" alt=""/><br /><sub><b>warp125</b></sub></a><br /><a href="#translation-warp125" title="Translation">🌍</a></td>
+  </tr>
+  <tr>
+    <td align="center"><a href="http://libkhadir.fr"><img src="https://avatars1.githubusercontent.com/u/45130488?v=4?s=100" width="100px;" alt=""/><br /><sub><b>KHADIR Tayeb</b></sub></a><br /><a href="#translation-tkhadir" title="Translation">🌍</a></td>
+    <td align="center"><a href="https://github.com/ignite1771"><img src="https://avatars2.githubusercontent.com/u/59446563?v=4?s=100" width="100px;" alt=""/><br /><sub><b>ignite1771</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=ignite1771" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/demirhalil"><img src="https://avatars1.githubusercontent.com/u/22895118?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Halil Demir</b></sub></a><br /><a href="#translation-demirhalil" title="Translation">🌍</a></td>
+    <td align="center"><a href="https://github.com/rohit10000"><img src="https://avatars.githubusercontent.com/u/20845565?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Rohit Singh</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=rohit10000" title="Code">💻</a></td>
+  </tr>
+  <tr>
+    <td align="center"><a href="https://github.com/byoungju94"><img src="https://avatars.githubusercontent.com/u/42516378?v=4?s=100" width="100px;" alt=""/><br /><sub><b>byoungju94</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=byoungju94" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/moustafafarhat"><img src="https://avatars.githubusercontent.com/u/38836727?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Moustafa Farhat</b></sub></a><br /><a href="#translation-moustafafarhat" title="Translation">🌍</a></td>
   </tr>
 </table>
 
-<!-- markdownlint-enable -->
+<!-- markdownlint-restore -->
 <!-- prettier-ignore-end -->
+
 <!-- ALL-CONTRIBUTORS-LIST:END -->

abstract-document/pom.xml

@@ -1,19 +1,28 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<!-- 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. -->
+<!--
+
+    The MIT License
+    Copyright © 2014-2021 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">
@@ -21,7 +30,7 @@
 	<parent>
 		<artifactId>java-design-patterns</artifactId>
 		<groupId>com.iluwatar</groupId>
-		<version>1.23.0-SNAPSHOT</version>
+		<version>1.24.0-SNAPSHOT</version>
 	</parent>
 	<artifactId>abstract-document</artifactId>
 	<dependencies>

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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
@@ -25,14 +25,23 @@ package com.iluwatar.abstractdocument;
 
 import org.junit.jupiter.api.Test;
 
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
+
 /**
  * Simple App test
  */
-public class AppTest {
+class AppTest {
+
+  /**
+   * Issue: Add at least one assertion to this test case.
+   *
+   * Solution: Inserted assertion to check whether the execution of the main method in {@link App}
+   * throws an exception.
+   */
 
   @Test
-  public void shouldExecuteAppWithoutException() {
-    App.main(null);
+  void shouldExecuteAppWithoutException() {
+    assertDoesNotThrow(() -> App.main(null));
   }
 
 }

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

abstract-factory/README.md

@@ -21,7 +21,7 @@ objects without specifying their concrete classes.
 
 Real world example
 
-> To create a kingdom we need objects with common theme. Elven kingdom needs an Elven king, Elven castle and Elven army whereas Orcish kingdom needs an Orcish king, Orcish castle and Orcish army. There is a dependency between the objects in the kingdom.
+> To create a kingdom we need objects with a common theme. Elven kingdom needs an Elven king, Elven castle and Elven army whereas Orcish kingdom needs an Orcish king, Orcish castle and Orcish army. There is a dependency between the objects in the kingdom.
 
 In plain words
 
@@ -33,7 +33,8 @@ Wikipedia says
 
 **Programmatic Example**
 
-Translating the kingdom example above. First of all we have some interfaces and implementation for the objects in the kingdom
+Translating the kingdom example above. First of all we have some interfaces and implementation for the objects in the 
+kingdom.
 
 ```java
 public interface Castle {
@@ -188,9 +189,9 @@ Use the Abstract Factory pattern when
 * 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:	
+Example use cases	
 
-* Selecting to call the appropriate implementation of FileSystemAcmeService or DatabaseAcmeService or NetworkAcmeService at runtime.
+* Selecting to call to the appropriate implementation of FileSystemAcmeService or DatabaseAcmeService or NetworkAcmeService at runtime.
 * Unit test case writing becomes much easier
 * UI tools for different OS
 
@@ -204,13 +205,17 @@ Use the Abstract Factory pattern when
 
 * [Abstract Factory Pattern Tutorial](https://www.journaldev.com/1418/abstract-factory-design-pattern-in-java) 
 
-
-## Real world examples
+## Known uses
 
 * [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--)
 
+## Related patterns
+
+* [Factory Method](https://java-design-patterns.com/patterns/factory-method/)
+* [Factory Kit](https://java-design-patterns.com/patterns/factory-kit/)
+
 ## Credits
 
 * [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)

abstract-factory/pom.xml

@@ -1,19 +1,28 @@
 <?xml version="1.0"?>
-<!-- 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. -->
+<!--
+
+    The MIT License
+    Copyright © 2014-2021 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"
@@ -22,7 +31,7 @@
 	<parent>
 		<groupId>com.iluwatar</groupId>
 		<artifactId>java-design-patterns</artifactId>
-		<version>1.23.0-SNAPSHOT</version>
+		<version>1.24.0-SNAPSHOT</version>
 	</parent>
 	<artifactId>abstract-factory</artifactId>
 	<dependencies>

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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
@@ -23,7 +23,6 @@
 
 package com.iluwatar.abstractfactory;
 
-import com.iluwatar.abstractfactory.App.FactoryMaker.KingdomType;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -41,84 +40,14 @@ import org.slf4j.LoggerFactory;
  * 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 {
+public class App implements Runnable {
 
-  private static final Logger LOGGER = LoggerFactory.getLogger(App.class);
+  private static Logger log = LoggerFactory.getLogger(App.class);
 
-  private King king;
-  private Castle castle;
-  private Army army;
+  private final Kingdom kingdom = new 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();
-  }
-
-  public King getKing() {
-    return king;
-  }
-
-  private void setKing(final King king) {
-    this.king = king;
-  }
-
-  Castle getCastle(final KingdomFactory factory) {
-    return factory.createCastle();
-  }
-
-  public Castle getCastle() {
-    return castle;
-  }
-
-  private void setCastle(final Castle castle) {
-    this.castle = castle;
-  }
-
-  Army getArmy(final KingdomFactory factory) {
-    return factory.createArmy();
-  }
-
-  public Army getArmy() {
-    return army;
-  }
-
-  private void setArmy(final Army army) {
-    this.army = army;
-  }
-
-  /**
-   * The factory of kingdom factories.
-   */
-  public static class FactoryMaker {
-
-    /**
-     * Enumeration for the different types of Kingdoms.
-     */
-    public enum KingdomType {
-      ELF, ORC
-    }
-
-    /**
-     * The factory method to create KingdomFactory concrete objects.
-     */
-    public static KingdomFactory makeFactory(KingdomType type) {
-      switch (type) {
-        case ELF:
-          return new ElfKingdomFactory();
-        case ORC:
-          return new OrcKingdomFactory();
-        default:
-          throw new IllegalArgumentException("KingdomType not supported.");
-      }
-    }
+  public Kingdom getKingdom() {
+    return kingdom;
   }
 
   /**
@@ -127,19 +56,33 @@ public class App {
    * @param args command line args
    */
   public static void main(String[] args) {
-
     var app = new App();
+    app.run();
+  }
 
-    LOGGER.info("Elf Kingdom");
-    app.createKingdom(FactoryMaker.makeFactory(KingdomType.ELF));
-    LOGGER.info(app.getArmy().getDescription());
-    LOGGER.info(app.getCastle().getDescription());
-    LOGGER.info(app.getKing().getDescription());
+  @Override
+  public void run() {
+    log.info("Elf Kingdom");
+    createKingdom(Kingdom.FactoryMaker.KingdomType.ELF);
+    log.info(kingdom.getArmy().getDescription());
+    log.info(kingdom.getCastle().getDescription());
+    log.info(kingdom.getKing().getDescription());
 
-    LOGGER.info("Orc Kingdom");
-    app.createKingdom(FactoryMaker.makeFactory(KingdomType.ORC));
-    LOGGER.info(app.getArmy().getDescription());
-    LOGGER.info(app.getCastle().getDescription());
-    LOGGER.info(app.getKing().getDescription());
+    log.info("Orc Kingdom");
+    createKingdom(Kingdom.FactoryMaker.KingdomType.ORC);
+    log.info(kingdom.getArmy().getDescription());
+    log.info(kingdom.getCastle().getDescription());
+    log.info(kingdom.getKing().getDescription());
+  }
+
+  /**
+   * Creates kingdom.
+   * @param kingdomType type of Kingdom
+   */
+  public void createKingdom(final Kingdom.FactoryMaker.KingdomType kingdomType) {
+    final KingdomFactory kingdomFactory = Kingdom.FactoryMaker.makeFactory(kingdomType);
+    kingdom.setKing(kingdomFactory.createKing());
+    kingdom.setCastle(kingdomFactory.createCastle());
+    kingdom.setArmy(kingdomFactory.createArmy());
   }
 }

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -0,0 +1,82 @@
+/*
+ * The MIT License
+ * Copyright © 2014-2021 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.abstractfactory;
+
+public class Kingdom {
+
+  private King king;
+  private Castle castle;
+  private Army army;
+
+  public King getKing() {
+    return king;
+  }
+
+  public Castle getCastle() {
+    return castle;
+  }
+
+  public Army getArmy() {
+    return army;
+  }
+
+  public void setKing(King king) {
+    this.king = king;
+  }
+
+  public void setCastle(Castle castle) {
+    this.castle = castle;
+  }
+
+  public void setArmy(Army army) {
+    this.army = army;
+  }
+
+  /**
+   * The factory of kingdom factories.
+   */
+  public static class FactoryMaker {
+
+    /**
+     * Enumeration for the different types of Kingdoms.
+     */
+    public enum KingdomType {
+      ELF, ORC
+    }
+
+    /**
+     * The factory method to create KingdomFactory concrete objects.
+     */
+    public static KingdomFactory makeFactory(KingdomType type) {
+      switch (type) {
+        case ELF:
+          return new ElfKingdomFactory();
+        case ORC:
+          return new OrcKingdomFactory();
+        default:
+          throw new IllegalArgumentException("KingdomType not supported.");
+      }
+    }
+  }
+}

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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
@@ -23,65 +23,71 @@
 
 package com.iluwatar.abstractfactory;
 
+import org.junit.jupiter.api.Test;
+
 import static org.junit.jupiter.api.Assertions.assertEquals;
 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.
  */
 public class AbstractFactoryTest {
 
   private final App app = new App();
-  private KingdomFactory elfFactory;
-  private KingdomFactory orcFactory;
-
-  @BeforeEach
-  public void setUp() {
-    elfFactory = FactoryMaker.makeFactory(KingdomType.ELF);
-    orcFactory = FactoryMaker.makeFactory(KingdomType.ORC);
-  }
 
   @Test
   public void king() {
-    final var elfKing = app.getKing(elfFactory);
+    app.createKingdom(Kingdom.FactoryMaker.KingdomType.ELF);
+    final var kingdom = app.getKingdom();
+
+    final var elfKing = kingdom.getKing();
     assertTrue(elfKing instanceof ElfKing);
     assertEquals(ElfKing.DESCRIPTION, elfKing.getDescription());
-    final var orcKing = app.getKing(orcFactory);
+
+    app.createKingdom(Kingdom.FactoryMaker.KingdomType.ORC);
+    final var orcKing = kingdom.getKing();
     assertTrue(orcKing instanceof OrcKing);
     assertEquals(OrcKing.DESCRIPTION, orcKing.getDescription());
   }
 
   @Test
   public void castle() {
-    final var elfCastle = app.getCastle(elfFactory);
+    app.createKingdom(Kingdom.FactoryMaker.KingdomType.ELF);
+    final var kingdom = app.getKingdom();
+
+    final var elfCastle = kingdom.getCastle();
     assertTrue(elfCastle instanceof ElfCastle);
     assertEquals(ElfCastle.DESCRIPTION, elfCastle.getDescription());
-    final var orcCastle = app.getCastle(orcFactory);
+
+    app.createKingdom(Kingdom.FactoryMaker.KingdomType.ORC);
+    final var orcCastle = kingdom.getCastle();
     assertTrue(orcCastle instanceof OrcCastle);
     assertEquals(OrcCastle.DESCRIPTION, orcCastle.getDescription());
   }
 
   @Test
   public void army() {
-    final var elfArmy = app.getArmy(elfFactory);
+    app.createKingdom(Kingdom.FactoryMaker.KingdomType.ELF);
+    final var kingdom = app.getKingdom();
+
+    final var elfArmy = kingdom.getArmy();
     assertTrue(elfArmy instanceof ElfArmy);
     assertEquals(ElfArmy.DESCRIPTION, elfArmy.getDescription());
-    final var orcArmy = app.getArmy(orcFactory);
+
+    app.createKingdom(Kingdom.FactoryMaker.KingdomType.ORC);
+    final var orcArmy = kingdom.getArmy();
     assertTrue(orcArmy instanceof OrcArmy);
     assertEquals(OrcArmy.DESCRIPTION, orcArmy.getDescription());
   }
 
   @Test
   public void createElfKingdom() {
-    app.createKingdom(elfFactory);
-    final var king = app.getKing();
-    final var castle = app.getCastle();
-    final var army = app.getArmy();
+    app.createKingdom(Kingdom.FactoryMaker.KingdomType.ELF);
+    final var kingdom = app.getKingdom();
+
+    final var king = kingdom.getKing();
+    final var castle = kingdom.getCastle();
+    final var army = kingdom.getArmy();
     assertTrue(king instanceof ElfKing);
     assertEquals(ElfKing.DESCRIPTION, king.getDescription());
     assertTrue(castle instanceof ElfCastle);
@@ -92,10 +98,12 @@ public class AbstractFactoryTest {
 
   @Test
   public void createOrcKingdom() {
-    app.createKingdom(orcFactory);
-    final var king = app.getKing();
-    final var castle = app.getCastle();
-    final var army = app.getArmy();
+    app.createKingdom(Kingdom.FactoryMaker.KingdomType.ORC);
+    final var kingdom = app.getKingdom();
+
+    final var king = kingdom.getKing();
+    final var castle = kingdom.getCastle();
+    final var army = kingdom.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 © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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
@@ -25,12 +25,23 @@ package com.iluwatar.abstractfactory;
 
 import org.junit.jupiter.api.Test;
 
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
+
 /**
  * Tests that Abstract Factory example runs without errors.
  */
-public class AppTest {
+class AppTest {
+
+  /**
+   * Issue: Add at least one assertion to this test case.
+   *
+   * Solution: Inserted assertion to check whether the execution of the main method in {@link App}
+   * throws an exception.
+   */
+
   @Test
-  public void test() {
-    App.main(new String[]{});
+  void shouldExecuteApplicationWithoutException() {
+
+    assertDoesNotThrow(() -> App.main(new String[]{}));
   }
 }

acyclic-visitor/README.md

@@ -101,7 +101,7 @@ public class ConfigureForUnixVisitor implements ZoomVisitor {
 }
 ```
 
-Finally here are the visitors in action.
+Finally, here are the visitors in action.
 
 ```java
     var conUnix = new ConfigureForUnixVisitor();

acyclic-visitor/pom.xml

@@ -1,18 +1,27 @@
-<!-- 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. -->
+<!--
+
+    The MIT License
+    Copyright © 2014-2021 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">
@@ -21,7 +30,7 @@
 	<parent>
 		<groupId>com.iluwatar</groupId>
 		<artifactId>java-design-patterns</artifactId>
-		<version>1.23.0-SNAPSHOT</version>
+		<version>1.24.0-SNAPSHOT</version>
 	</parent>
 
 	<artifactId>acyclic-visitor</artifactId>

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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
@@ -25,13 +25,23 @@ package com.iluwatar.acyclicvisitor;
 
 import org.junit.jupiter.api.Test;
 
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
+
 /**
  * Tests that the Acyclic Visitor example runs without errors.
  */
-public class AppTest {
+class AppTest {
+
+  /**
+   * Issue: Add at least one assertion to this test case.
+   *
+   * Solution: Inserted assertion to check whether the execution of the main method in {@link App}
+   * throws an exception.
+   */
 
   @Test
-  public void test() {
-    App.main(new String[]{});
+  void shouldExecuteApplicationWithoutException() {
+
+    assertDoesNotThrow(() -> App.main(new String[]{}));
   }
 }

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

adapter/README.md

@@ -12,9 +12,8 @@ tags:
 Wrapper
 
 ## Intent
-Convert the interface of a class into another interface the clients
-expect. Adapter lets classes work together that couldn't otherwise because of
-incompatible interfaces.
+Convert the interface of a class into another interface the clients expect. Adapter lets classes work together that 
+couldn't otherwise because of incompatible interfaces.
 
 ## Explanation
 

adapter/pom.xml

@@ -1,19 +1,28 @@
 <?xml version="1.0"?>
-<!-- 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. -->
+<!--
+
+    The MIT License
+    Copyright © 2014-2021 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"
@@ -22,7 +31,7 @@
 	<parent>
 		<groupId>com.iluwatar</groupId>
 		<artifactId>java-design-patterns</artifactId>
-		<version>1.23.0-SNAPSHOT</version>
+		<version>1.24.0-SNAPSHOT</version>
 	</parent>
 	<artifactId>adapter</artifactId>
 	<dependencies>

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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
@@ -25,12 +25,23 @@ package com.iluwatar.adapter;
 
 import org.junit.jupiter.api.Test;
 
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
+
 /**
  * Tests that Adapter example runs without errors.
  */
-public class AppTest {
+class AppTest {
+
+  /**
+   * Issue: Add at least one assertion to this test case.
+   *
+   * Solution: Inserted assertion to check whether the execution of the main method in {@link App}
+   * throws an exception.
+   */
+
   @Test
-  public void test() {
-    App.main(new String[]{});
+  void shouldExecuteApplicationWithoutException() {
+
+    assertDoesNotThrow(() -> App.main(new String[]{}));
   }
 }

aggregator-microservices/README.md

@@ -6,20 +6,97 @@ permalink: /patterns/aggregator-microservices/
 categories: Architectural
 tags:
 - Cloud distributed
+- Decoupling
+- Microservices
 ---
 
 ## Intent
 
-The user makes a single call to the Aggregator, and the aggregator then calls each relevant microservice and collects
-the data, apply business logic to it, and further publish is as a REST Endpoint.
-More variations of the aggregator are: 
-- Proxy Microservice Design Pattern: A different microservice is called upon the business need. 
-- Chained Microservice Design Pattern: In this case each microservice is dependent/ chained to a series 
-of other microservices.
+The user makes a single call to the aggregator service, and the aggregator then calls each relevant microservice.
+
+## Explanation
+
+Real world example
+
+> Our web marketplace needs information about products and their current inventory. It makes a call to an aggregator
+> service which in turn calls the product information microservice and product inventory microservice returning the
+> combined information. 
+
+In plain words
+
+> Aggregator Microservice collects pieces of data from various microservices and returns an aggregate for processing. 
+
+Stack Overflow says
+
+> Aggregator Microservice invokes multiple services to achieve the functionality required by the application.
+
+**Programmatic Example**
+
+Let's start from the data model. Here's our `Product`.
+
+```java
+public class Product {
+  private String title;
+  private int productInventories;
+  // getters and setters ->
+  ...
+}
+```
+
+Next we can introduce our `Aggregator` microservice. It contains clients `ProductInformationClient` and
+`ProductInventoryClient` for calling respective microservices.
+
+```java
+@RestController
+public class Aggregator {
+
+  @Resource
+  private ProductInformationClient informationClient;
+
+  @Resource
+  private ProductInventoryClient inventoryClient;
+
+  @RequestMapping(path = "/product", method = RequestMethod.GET)
+  public Product getProduct() {
+
+    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;
+  }
+}
+```
+
+Here's the essence of information microservice implementation. Inventory microservice is similar, it just returns
+inventory counts.
+
+```java
+@RestController
+public class InformationController {
+  @RequestMapping(value = "/information", method = RequestMethod.GET)
+  public String getProductTitle() {
+    return "The Product Title.";
+  }
+}
+```
+
+Now calling our `Aggregator` REST API returns the product information.
+
+```bash
+curl http://localhost:50004/product
+{"title":"The Product Title.","productInventories":5}
+```
 
 ## Class diagram
 
-![alt text](./etc/aggregator-microservice.png "Aggregator Microservice")
+![alt text](./aggregator-service/etc/aggregator-service.png "Aggregator Microservice")
 
 ## Applicability
 
@@ -28,3 +105,5 @@ Use the Aggregator Microservices pattern when you need a unified API for various
 ## Credits
 
 * [Microservice Design Patterns](http://web.archive.org/web/20190705163602/http://blog.arungupta.me/microservice-design-patterns/)
+* [Microservices Patterns: With examples in Java](https://www.amazon.com/gp/product/1617294543/ref=as_li_qf_asin_il_tl?ie=UTF8&tag=javadesignpat-20&creative=9325&linkCode=as2&creativeASIN=1617294543&linkId=8b4e570267bc5fb8b8189917b461dc60)
+* [Architectural Patterns: Uncover essential patterns in the most indispensable realm of enterprise architecture](https://www.amazon.com/gp/product/B077T7V8RC/ref=as_li_qf_asin_il_tl?ie=UTF8&tag=javadesignpat-20&creative=9325&linkCode=as2&creativeASIN=B077T7V8RC&linkId=c34d204bfe1b277914b420189f09c1a4)

aggregator-microservices/aggregator-service/pom.xml

@@ -1,26 +1,35 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<!-- 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. -->
+<!--
+
+    The MIT License
+    Copyright © 2014-2021 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>1.23.0-SNAPSHOT</version>
+		<version>1.24.0-SNAPSHOT</version>
 	</parent>
 	<modelVersion>4.0.0</modelVersion>
 	<artifactId>aggregator-service</artifactId>

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 #
 # The MIT License
-# Copyright © 2014-2019 Ilkka Seppälä
+# Copyright © 2014-2021 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
@@ -20,4 +20,5 @@
 # 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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

aggregator-microservices/information-microservice/pom.xml

@@ -1,26 +1,35 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<!-- 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. -->
+<!--
+
+    The MIT License
+    Copyright © 2014-2021 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>1.23.0-SNAPSHOT</version>
+		<version>1.24.0-SNAPSHOT</version>
 	</parent>
 	<modelVersion>4.0.0</modelVersion>
 

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 #
 # The MIT License
-# Copyright © 2014-2019 Ilkka Seppälä
+# Copyright © 2014-2021 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
@@ -20,4 +20,5 @@
 # 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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

aggregator-microservices/inventory-microservice/pom.xml

@@ -1,26 +1,35 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<!-- 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. -->
+<!--
+
+    The MIT License
+    Copyright © 2014-2021 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>1.23.0-SNAPSHOT</version>
+		<version>1.24.0-SNAPSHOT</version>
 	</parent>
 	<modelVersion>4.0.0</modelVersion>
 	<artifactId>inventory-microservice</artifactId>

aggregator-microservices/inventory-microservice/src/main/java/com/iluwatar/inventory/microservice/InventoryApplication.java

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

aggregator-microservices/inventory-microservice/src/main/java/com/iluwatar/inventory/microservice/InventoryController.java

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 #
 # The MIT License
-# Copyright © 2014-2019 Ilkka Seppälä
+# Copyright © 2014-2021 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
@@ -20,4 +20,5 @@
 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 # THE SOFTWARE.
 #
+
 server.port=51516

aggregator-microservices/inventory-microservice/src/test/java/com/iluwatar/inventory/microservice/InventoryControllerTest.java

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

aggregator-microservices/pom.xml

@@ -2,7 +2,7 @@
 <!--
 
     The MIT License
-    Copyright © 2014-2019 Ilkka Seppälä
+    Copyright © 2014-2021 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
@@ -29,7 +29,7 @@
     <parent>
         <artifactId>java-design-patterns</artifactId>
         <groupId>com.iluwatar</groupId>
-        <version>1.23.0-SNAPSHOT</version>
+        <version>1.24.0-SNAPSHOT</version>
     </parent>
     <modelVersion>4.0.0</modelVersion>
     <artifactId>aggregator-microservices</artifactId>

ambassador/README.md

@@ -10,28 +10,37 @@ tags:
 ---
 
 ## Intent
+
 Provide a helper service instance on a client and offload common functionality away from a shared resource.
 
 ## Explanation
+
 Real world example
 
-> A remote service has many clients accessing a function it provides. The service is a legacy application and is impossible to update. Large numbers of requests from users are causing connectivity issues. New rules for request frequency should be implemented along with latency checks and client-side logging.
+> A remote service has many clients accessing a function it provides. The service is a legacy application and is 
+> impossible to update. Large numbers of requests from users are causing connectivity issues. New rules for request 
+> frequency should be implemented along with latency checks and client-side logging.
 
 In plain words
 
-> Using the ambassador pattern, we can implement less-frequent polling from clients along with latency checks and logging.
+> With the Ambassador pattern, we can implement less-frequent polling from clients along with latency checks and 
+> logging.
 
 Microsoft documentation states
 
-> An ambassador service can be thought of as an out-of-process proxy that is co-located with the client. This pattern can be useful for offloading common client connectivity tasks such as monitoring, logging, routing, security (such as TLS), and resiliency patterns in a language agnostic way. It is often used with legacy applications, or other applications that are difficult to modify, in order to extend their networking capabilities. It can also enable a specialized team to implement those features.
+> An ambassador service can be thought of as an out-of-process proxy which is co-located with the client. This pattern 
+> can be useful for offloading common client connectivity tasks such as monitoring, logging, routing, 
+> security (such as TLS), and resiliency patterns in a language agnostic way. It is often used with legacy applications, 
+> or other applications that are difficult to modify, in order to extend their networking capabilities. It can also 
+> enable a specialized team to implement those features.
 
 **Programmatic Example**
 
-With the above example in mind we will imitate the functionality in a simple manner. We have an interface implemented by the remote service as well as the ambassador service:
+With the above introduction in mind we will imitate the functionality in this example. We have an interface implemented 
+by the remote service as well as the ambassador service:
 
 ```java
 interface RemoteServiceInterface {
-
     long doRemoteFunction(int value) throws Exception;
 }
 ```
@@ -136,7 +145,7 @@ public class Client {
 }
 ```
 
-And here are two clients using the service.
+Here are two clients using the service.
 
 ```java
 public class App {
@@ -149,13 +158,29 @@ public class App {
 }
 ```
 
+Here's the output for running the example:
+
+```java
+Time taken (ms): 111
+Service result: 120
+Time taken (ms): 931
+Failed to reach remote: (1)
+Time taken (ms): 665
+Failed to reach remote: (2)
+Time taken (ms): 538
+Failed to reach remote: (3)
+Service result: -1
+```
+
 ## Class diagram
+
 ![alt text](./etc/ambassador.urm.png "Ambassador class diagram")
 
 ## Applicability
-Ambassador is applicable when working with a legacy remote service that cannot
-be modified or would be extremely difficult to modify. Connectivity features can
-be implemented on the client avoiding the need for changes on the remote service.
+
+Ambassador is applicable when working with a legacy remote service which cannot be modified or would be extremely 
+difficult to modify. Connectivity features can be implemented on the client avoiding the need for changes on the remote 
+service.
 
 * Ambassador provides a local interface for a remote service.
 * Ambassador provides logging, circuit breaking, retries and security on the client.
@@ -168,10 +193,14 @@ be implemented on the client avoiding the need for changes on the remote service
 * Offload remote service tasks
 * Facilitate network connection
 
-## Real world examples
+## Known uses
 
 * [Kubernetes-native API gateway for microservices](https://github.com/datawire/ambassador)
 
+## Related patterns
+
+* [Proxy](https://java-design-patterns.com/patterns/proxy/)
+
 ## Credits
 
 * [Ambassador pattern](https://docs.microsoft.com/en-us/azure/architecture/patterns/ambassador)

ambassador/pom.xml

@@ -1,26 +1,35 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<!-- 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. -->
+<!--
+
+    The MIT License
+    Copyright © 2014-2021 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>java-design-patterns</artifactId>
 		<groupId>com.iluwatar</groupId>
-		<version>1.23.0-SNAPSHOT</version>
+		<version>1.24.0-SNAPSHOT</version>
 	</parent>
 	<modelVersion>4.0.0</modelVersion>
 	<artifactId>ambassador</artifactId>

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

ambassador/src/main/java/com/iluwatar/ambassador/Client.java

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

ambassador/src/main/java/com/iluwatar/ambassador/RemoteService.java

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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
@@ -62,7 +62,7 @@ public class RemoteService implements RemoteServiceInterface {
    *
    * @param value integer value to be multiplied.
    * @return if waitTime is less than {@link RemoteService#THRESHOLD}, it returns value * 10,
-   *     otherwise {@link RemoteServiceInterface#FAILURE}.
+   *     otherwise {@link RemoteServiceStatus#FAILURE}.
    */
   @Override
   public long doRemoteFunction(int value) {
@@ -74,6 +74,7 @@ public class RemoteService implements RemoteServiceInterface {
     } catch (InterruptedException e) {
       LOGGER.error("Thread sleep state interrupted", e);
     }
-    return waitTime <= THRESHOLD ? value * 10 : FAILURE;
+    return waitTime <= THRESHOLD ? value * 10
+            : RemoteServiceStatus.FAILURE.getRemoteServiceStatusValue();
   }
 }

ambassador/src/main/java/com/iluwatar/ambassador/RemoteServiceInterface.java

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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
@@ -27,7 +27,6 @@ package com.iluwatar.ambassador;
  * Interface shared by ({@link RemoteService}) and ({@link ServiceAmbassador}).
  */
 interface RemoteServiceInterface {
-  int FAILURE = -1;
 
-  long doRemoteFunction(int value) throws Exception;
+  long doRemoteFunction(int value);
 }

ambassador/src/main/java/com/iluwatar/ambassador/RemoteServiceStatus.java

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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
@@ -21,37 +21,28 @@
  * THE SOFTWARE.
  */
 
-package com.iluwatar.command;
+package com.iluwatar.ambassador;
 
 /**
- * InvisibilitySpell is a concrete command.
+ * Holds information regarding the status of the Remote Service.
+ *
+ * <p> This Enum replaces the integer value previously
+ * stored in {@link RemoteServiceInterface} as SonarCloud was identifying
+ * it as an issue. All test cases have been checked after changes,
+ * without failures. </p>
  */
-public class InvisibilitySpell extends Command {
 
-  private Target target;
+public enum RemoteServiceStatus {
+  FAILURE(-1)
+  ;
 
-  @Override
-  public void execute(Target target) {
-    target.setVisibility(Visibility.INVISIBLE);
-    this.target = target;
+  private final long remoteServiceStatusValue;
+
+  RemoteServiceStatus(long remoteServiceStatusValue) {
+    this.remoteServiceStatusValue = remoteServiceStatusValue;
   }
 
-  @Override
-  public void undo() {
-    if (target != null) {
-      target.setVisibility(Visibility.VISIBLE);
-    }
-  }
-
-  @Override
-  public void redo() {
-    if (target != null) {
-      target.setVisibility(Visibility.INVISIBLE);
-    }
-  }
-
-  @Override
-  public String toString() {
-    return "Invisibility spell";
+  public long getRemoteServiceStatusValue() {
+    return remoteServiceStatusValue;
   }
 }

ambassador/src/main/java/com/iluwatar/ambassador/ServiceAmbassador.java

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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
@@ -23,6 +23,7 @@
 
 package com.iluwatar.ambassador;
 
+import static com.iluwatar.ambassador.RemoteServiceStatus.FAILURE;
 import static java.lang.Thread.sleep;
 
 import org.slf4j.Logger;
@@ -58,14 +59,14 @@ public class ServiceAmbassador implements RemoteServiceInterface {
 
   private long safeCall(int value) {
     var retries = 0;
-    var result = (long) FAILURE;
+    var result = FAILURE.getRemoteServiceStatusValue();
 
     for (int i = 0; i < RETRIES; i++) {
       if (retries >= RETRIES) {
-        return FAILURE;
+        return FAILURE.getRemoteServiceStatusValue();
       }
 
-      if ((result = checkLatency(value)) == FAILURE) {
+      if ((result = checkLatency(value)) == FAILURE.getRemoteServiceStatusValue()) {
         LOGGER.info("Failed to reach remote: (" + (i + 1) + ")");
         retries++;
         try {

ambassador/src/main/java/com/iluwatar/ambassador/util/RandomProvider.java

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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

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

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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
@@ -25,13 +25,23 @@ package com.iluwatar.ambassador;
 
 import org.junit.jupiter.api.Test;
 
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
+
 /**
  * Application test
  */
 class AppTest {
 
+  /**
+   * Issue: Add at least one assertion to this test case.
+   *
+   * Solution: Inserted assertion to check whether the execution of the main method in {@link App}
+   * throws an exception.
+   */
+
   @Test
-  void test() {
-    App.main(new String[]{});
+  void shouldExecuteApplicationWithoutException() {
+
+    assertDoesNotThrow(() -> App.main(new String[]{}));
   }
 }

ambassador/src/test/java/com/iluwatar/ambassador/ClientTest.java

@@ -1,6 +1,6 @@
 /*
  * The MIT License
- * Copyright © 2014-2019 Ilkka Seppälä
+ * Copyright © 2014-2021 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
@@ -37,6 +37,6 @@ class ClientTest {
     Client client = new Client();
     var result = client.useService(10);
 
-    assertTrue(result == 100 || result == RemoteService.FAILURE);
+    assertTrue(result == 100 || result == RemoteServiceStatus.FAILURE.getRemoteServiceStatusValue());
   }
 }