Design patterns implemented in Java

Overview

Design patterns implemented in Java

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Introduction

Design patterns are the best formalized practices a programmer can use to solve common problems when designing an application or system.

Design patterns can speed up the development process by providing tested, proven development paradigms.

Reusing design patterns help prevent subtle issues that cause major problems, and it also improves code readability for coders and architects who are familiar with the patterns.

Getting started

This site showcases Java Design Patterns. The solutions have been developed by experienced programmers and architects from the open source community. The patterns can be browsed by their high level descriptions or by looking at their source code. The source code examples are well commented and can be thought as programming tutorials 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 Software Design Principles.

All designs should be as simple as possible. You should start with KISS, YAGNI, and Do The Simplest Thing That Could Possibly Work principles. Complexity and patterns should only be introduced when they are needed for practical extensibility.

Once you are familiar with these concepts you can start drilling down into the available design patterns by any of the following approaches

  • Search for a specific pattern by name. Can't find one? Please report a new pattern here.
  • Using tags such as Performance, Gang of Four or Data access.
  • Using pattern categories, Creational, Behavioral, and others.

Hopefully you find the object oriented solutions presented on this site useful in your architectures and have as much fun learning them as we had developing them.

How to contribute

If you are willing to contribute to the project you will find the relevant information in our developer wiki. We will help you and answer your questions in the Gitter chatroom.

License

This project is licensed under the terms of the MIT license.

Contributors


Ilkka SeppΓ€lΓ€

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amit1307

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Narendra Pathai

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Jeroen Meulemeester

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Joseph McCarthy

πŸ’»

Thomas

πŸ’»

Anurag Agarwal

πŸ’»

Markus Moser

🎨 πŸ’» πŸ€”

Sabiq Ihab

πŸ’»

Amit Dixit

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Piyush Kailash Chaudhari

πŸ’»

joshzambales

πŸ’»

Kamil Pietruszka

πŸ’»

Zafar Khaydarov

πŸ’» πŸ“–

Paul Campbell

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Argyro Sioziou

πŸ’»

TylerMcConville

πŸ’»

saksham93

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nikhilbarar

πŸ’»

Colin But

πŸ’»

Ruslan

πŸ’»

Juho Kang

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Dheeraj Mummareddy

πŸ’»

Bernardo Sulzbach

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Aleksandar Dudukovic

πŸ’»

Yusuf Aytaş

πŸ’»

MihΓ‘ly Kuprivecz

πŸ’»

Stanislav Kapinus

πŸ’»

GVSharma

πŸ’»

Srđan Paunović

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Petros G. Sideris

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Pramod Gupta

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Amarnath Chandana

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Anurag870

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Wes Gilleland

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Harshraj Thakor

πŸ’»

Martin Vandenbussche

πŸ’»

Alexandru Somai

πŸ’»

Artur Mogozov

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anthony

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Christian Cygnus

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Dima Gubin

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Joshua Jimenez

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Kai Winter

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lbroman

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Przemek

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Prafful Agarwal

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Sanket Panhale

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staillebois

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KrisztiΓ‘n Nagy

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Alexander Ivanov

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Yosfik Alqadri

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AgustΓ­ Becerra MilΓ 

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Juan Manuel SuΓ‘rez

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Luigi Cortese

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Katarzyna Rzepecka

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adamski.pro

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Shengli Bai

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Boris

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Dmitry Avershin

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靳阳

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hoangnam2261

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Arpit Jain

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JΓ³n Ingi SveinbjΓΆrnsson

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Kirill Vlasov

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Mitchell Irvin

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Ranjeet

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PhoenixYip

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M Saif Asif

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kanwarpreet25

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Leon Mak

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Per Wramdemark

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Evan Sia Wai Suan

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AnaghaSasikumar

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Christoffer Hamberg

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Dominik Gruntz

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Hannes

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Leo GutiΓ©rrez RamΓ­rez

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Zhang WH

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Christopher O'Connell

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George Mavroeidis

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Hemant Bothra

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Kevin Peters

πŸ’»

George Aristy

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Mahendran Mookkiah

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Azureyjt

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gans

πŸ’»

Matt

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Gopinath Langote

πŸ’»

Hoswey

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Amit Pandey

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gwildor28

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η”°ζ΅©

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Stamatis Pitsios

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qza

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Rodolfo Forte

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Ankur Kaushal

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Ovidijus Okinskas

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Robert Kasperczyk

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Tapio Rautonen

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Yuri Orlov

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Varun Upadhyay

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Aditya Pal

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grzesiekkedzior

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Sivasubramani M

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Sami Airaksinen

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Janne Sinivirta

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Boris-Chengbiao Zhou

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Jacob Hein

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Richard Jones

πŸ–‹

Rachel M. Carmena

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Zaerald Denze Lungos

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Lars Kappert

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Mike Liu

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Matt Dolan

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Manan

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Nishant Arora

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Peeyush

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Rakesh

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Wei Seng

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Ashish Trivedi

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ζ΄ͺ月阳

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xdvrx1

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Subhrodip Mohanta

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Bethan Palmer

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Toxic Dreamz

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Edy Cu Tjong

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MichaΕ‚ KrzywaΕ„ski

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Stefan Birkner

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Fedor Skvorcov

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samilAyoub

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Vladislav Golubinov

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Swaraj

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Christoph Flick

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AscΓͺnio

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Domenico Sibilio

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Akash Chandwani

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Pavlo Manannikov

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Eiman

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Rocky

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Ibrahim ali abdelghany

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Girish Kulkarni

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Omar Karazoun

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Jeff Evans

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Vivek Singh

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siavash

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ruchpeanuts

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warp125

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KHADIR Tayeb

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ignite1771

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Halil Demir

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Rohit Singh

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byoungju94

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Moustafa Farhat

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Martel Richard

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va1m

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Noam Greenshtain

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Comments
  • SonarCloud reports issues

    SonarCloud reports issues

    The project is using SonarCloud static code analysis. The latest results are showing that it has found several blockers and critical severity code smells (major, minor, and info level we ignore). In this task, those are fixed or marked as false positives. To mark false positives, SuppressWarnings annotation should be used in code as explained in the linked documentation.

    Links: Blocker and critical severity code smells in SonarCloud Sonar false positives


    Note: When Submitting a PR please provide a hyperlinked list of all the issues that you are issuing a fix for. See this example

    type: bug info: good first issue type: refactoring epic: code quality 
    opened by iluwatar 43
  • Explanation for design patterns

    Explanation for design patterns

    We want to present the design patterns better as the current does not reach its goal of explaining how the pattern works in a simplest possible way. I'm hugely inspired by https://github.com/kamranahmedse/design-patterns-for-humans repository.

    Let's do this by adding 'Explanation' section to the patterns' README.md file. For an example see http://java-design-patterns.com/patterns/bridge/.

    Let's track the issue progress here with the following checklist that indicates the patterns where explanation section is already available.

    • [x] abstract-document
    • [x] abstract-factory
    • [x] active-object
    • [x] acyclic-visitor
    • [x] adapter
    • [x] aggregator-microservices
    • [x] ambassador
    • [x] api-gateway
    • [x] arrange-act-assert
    • [x] async-method-invocation
    • [x] balking
    • [x] bridge
    • [x] builder
    • [x] business-delegate
    • [x] bytecode
    • [x] caching
    • [x] callback
    • [x] chain
    • [x] circuit-breaker
    • [x] cloud-static-content-hosting
    • [ ] collection-pipeline
    • [ ] combinator
    • [x] command
    • [ ] commander
    • [x] composite
    • [x] composite-entity
    • [x] converter
    • [ ] cqrs
    • [x] dao
    • [ ] data-bus
    • [ ] data-locality
    • [ ] data-mapper
    • [x] data-transfer-object
    • [x] decorator
    • [ ] delegation
    • [x] dependency-injection
    • [ ] dirty-flag
    • [ ] double-buffer
    • [ ] double-checked-locking
    • [ ] double-dispatch
    • [ ] eip-aggregator
    • [ ] eip-message-channel
    • [ ] eip-publish-subscribe
    • [ ] eip-splitter
    • [ ] eip-wire-tap
    • [ ] event-aggregator
    • [ ] event-based-asynchronous
    • [ ] event-driven-architecture
    • [ ] event-queue
    • [ ] event-sourcing
    • [x] execute-around
    • [ ] extension-objects
    • [x] facade
    • [x] factory
    • [ ] factory-kit
    • [x] factory-method
    • [ ] fan-out-fan-in
    • [ ] feature-toggle
    • [x] filterer
    • [x] fluentinterface
    • [ ] flux
    • [x] flyweight
    • [ ] front-controller
    • [x] game-loop
    • [ ] guarded-suspension
    • [ ] half-sync-half-async
    • [ ] hexagonal
    • [ ] intercepting-filter
    • [x] interpreter
    • [x] iterator
    • [x] layers
    • [ ] lazy-loading
    • [ ] leader-election
    • [ ] leader-followers
    • [x] lockable-object
    • [ ] marker-interface
    • [ ] master-worker
    • [x] mediator
    • [x] memento
    • [ ] model-view-controller
    • [ ] model-view-presenter
    • [x] model-view-viewmodel
    • [ ] module
    • [ ] monad
    • [ ] monostate
    • [x] multiton
    • [ ] mute-idiom
    • [ ] naked-objects
    • [x] null-object
    • [ ] object-mother
    • [x] object-pool
    • [x] observer
    • [ ] page-object
    • [x] parameter-object
    • [ ] partial-response
    • [x] pipeline
    • [x] poison-pill
    • [x] presentation-model
    • [x] priority-queue
    • [x] private-class-data
    • [ ] producer-consumer
    • [x] promise
    • [ ] property
    • [x] prototype
    • [x] proxy
    • [ ] queue-based-load-leveling
    • [ ] reactor
    • [ ] reader-writer-lock
    • [x] registry
    • [x] repository
    • [ ] resource-acquisition-is-initialization
    • [x] retry
    • [ ] role-object
    • [ ] saga
    • [ ] semaphore
    • [x] separated-interface
    • [ ] servant
    • [ ] serverless
    • [ ] service-layer
    • [ ] service-locator
    • [ ] sharding
    • [x] singleton
    • [x] spatial-partition
    • [x] special-case
    • [x] specification
    • [x] state
    • [ ] step-builder
    • [ ] strangler
    • [x] strategy
    • [ ] subclass-sandbox
    • [x] table-module
    • [x] template-method
    • [x] thread-pool
    • [x] throttling
    • [ ] thread-local-storage
    • [x] tolerant-reader
    • [x] trampoline
    • [x] transaction-script
    • [x] twin
    • [ ] type-object
    • [x] unit-of-work
    • [ ] update-method
    • [ ] value-object
    • [x] version-number
    • [x] visitor
    info: help wanted epic: pattern type: enhancement epic: web site info: good first issue info: needs splitting epic: design 
    opened by iluwatar 40
  • Translation to other languages

    Translation to other languages

    #I think this is a very nice repo to learn java design patterns.But as I see, there still no translations for other languages.So I want to join this repo and translate this into chinese if It's possible.(I' m a Chinese)

    epic: web site info: needs splitting epic: architecture type: feature 
    opened by xiaod-dev 30
  • Attach tutorial links to patterns

    Attach tutorial links to patterns

    In the pattern template there is section for Tutorials. Here we should list tutorials explaining the pattern. One example is here http://java-design-patterns.com/patterns/hexagonal/.

    epic: pattern type: enhancement info: good first issue 
    opened by iluwatar 29
  • Checkstyle reports warnings

    Checkstyle reports warnings

    In issue https://github.com/iluwatar/java-design-patterns/issues/1016 we switched using Checkstyle's builtin google_checks.xml. The new ruleset finds over 6k warnings. In this issue we try fix those gradually, one pattern at a time. If you want to help, please comment on the issue which patterns will you be working on. We will follow the progress using the following table.

    [x] abstract-document [x] abstract-factory [x] acyclic-visitor [x] adapter [x] aggregator-microservices [x] ambassador [x] api-gateway [x] async-method-invocation [x] balking [x] bridge [x] builder [x] business-delegate [x] bytecode [x] caching [x] callback [x] chain [x] circuit breaker [x] collection-pipeline [x] command [x] commander [x] composite [x] converter [x] cqrs [x] dao [x] data-bus [x] data-locality [x] data-mapper [x] data-transfer-object [x] decorator [x] delegation [x] dependency-injection [x] dirty-flag [x] double-checked-locking [x] double-dispatch [x] eip-aggregator [x] eip-message-channel [x] eip-publish-subscribe [x] eip-splitter [x] eip-wire-tap [x] event-aggregator [x] event-asynchronous [x] event-driven-architecture [x] event-queue [x] event-sourcing [x] execute-around [x] extension-objects [x] facade [x] factory-kit [x] factory-method [x] feature-toggle [x] fluentinterface [x] flux [x] flyweight [x] front-controller [x] guarded-suspension [x] half-sync-half-async [x] hexagonal [x] intercepting-filter [x] interpreter [x] iterator [x] layers [x] lazy-loading [x] leader-election [x] marker [x] master-worker-pattern [x] mediator [x] memento [x] model-view-controller [x] model-view-presenter [x] module [x] monad [x] monostate [x] multiton [x] mute-idiom [x] mutex [x] naked-objects [x] null-object [x] object-mother [x] object-pool [x] observer [x] page-object [x] partial-response [x] pipeline [x] poison-pill [x] priority-queue [x] private-class-data [x] producer-consumer [x] promise [x] property [x] prototype [x] proxy [x] queue-load-leveling [x] reactor [x] reader-writer-lock [x] repository [x] resource-acquisition-is-initialization [x] retry [x] semaphore [x] servant [x] serverless [x] service-layer [x] service-locator [x] singleton [x] spatial-partition [x] specification [x] state [x] step-builder [x] strategy [x] template-method [x] thread-pool [x] throttling [x] tls [x] tolerant-reader [x] trampoline [x] twin [x] typeobjectpattern [x] unit-of-work [x] value-object [x] visitor

    Links: https://github.com/checkstyle/checkstyle/blob/master/src/main/resources/google_checks.xml https://google.github.io/styleguide/javaguide.html

    info: help wanted info: good first issue type: refactoring epic: code quality 
    opened by iluwatar 28
  • Accepting presentations for the design patterns

    Accepting presentations for the design patterns

    @iluwatar What do u think if we create presentations for these nice collections of design patterns. Either one for each for one for all. Something based on impress.js or similar would be great I think. Happy to contribute. Kiitos

    info: help wanted type: enhancement info: needs splitting resolution: won't fix 
    opened by zafarella 26
  • Java 11 support: Utilize new methods

    Java 11 support: Utilize new methods

    This task is part of the Java 11 transition plan https://github.com/iluwatar/java-design-patterns/wiki/16.-Java-11-Transition

    This is a refactoring ticket where we start to utilize new Java 11 functionality.

    1. Collecting to unmodifiable collections is possible using the new Collector for Streams operations to put the results into an immutable collection (see https://www.infoq.com/articles/upgrading-java-8-to-12/)

    2. Predicate::not provides an easy way to negate predicate lambdas or method references, again reducing the boilerplate in our code (see https://www.infoq.com/articles/upgrading-java-8-to-12/)

    3. New methods on Optional give even more options for coding in a functional style when using an Optional instead of having to use clumsy if statements (see https://winterbe.com/posts/2018/09/24/java-11-tutorial/)

    4. Streams have new methods ofNullable, dropWhile, takeWhile (see https://winterbe.com/posts/2018/09/24/java-11-tutorial/)

    5. String has new helper methods (see https://winterbe.com/posts/2018/09/24/java-11-tutorial/)

    6. InputStream finally gets a super useful method to transfer data to an OutputStream (see https://winterbe.com/posts/2018/09/24/java-11-tutorial/)

    7. Convenience Factory Methods for Collections make it significantly easier to create collections like lists, maps and sets (see https://winterbe.com/posts/2018/09/24/java-11-tutorial/)

    It's a huge task to do this for all the patterns at once so it is possible to create pull requests for individual patterns. This way we can complete the task gradually. The following checklist tracks which patterns have already been refactored.

    [x] abstract-document [x] abstract-factory [x] acyclic-visitor [x] adapter [x] aggregator-microservices [x] ambassador [x] api-gateway [x] async-method-invocation [x] balking [x] bridge [x] builder [x] business-delegate [x] bytecode [x] caching [x] callback [x] chain [x] circuit-breaker [x] collection-pipeline [x] command [x] commander [x] composite [x] converter [x] cqrs [x] dao [x] data-bus [x] data-locality [x] data-mapper [x] data-transfer-object [x] decorator [x] delegation [x] dependency-injection [x] dirty-flag [x] double-checked-locking [x] double-dispatch [x] eip-aggregator [x] eip-message-channel [x] eip-publish-subscribe [x] eip-splitter [x] eip-wire-tap [x] event-aggregator [x] event-asynchronous [x] event-driven-architecture [x] event-queue [x] event-sourcing [x] execute-around [x] extension-objects [x] facade [x] factory-kit [x] factory-method [x] faq.md [x] feature-toggle [x] fluentinterface [x] flux [x] flyweight [x] front-controller [x] guarded-suspension [x] half-sync-half-async [x] hexagonal [x] intercepting-filter [x] interpreter [x] iterator [x] layers [x] lazy-loading [x] leader-election [x] marker [x] master-worker-pattern [x] mediator [x] memento [x] model-view-controller [x] model-view-presenter [x] module [x] monad [x] monostate [x] multiton [x] mute-idiom [x] mutex [x] naked-objects [x] null-object [x] object-mother [x] object-pool [x] observer [x] page-object [x] partial-response [x] pipeline [x] poison-pill [x] priority-queue [x] private-class-data [x] producer-consumer [x] promise [x] property [x] prototype [x] proxy [x] queue-load-leveling [x] reactor [x] reader-writer-lock [x] repository [x] resource-acquisition-is-initialization [x] retry [x] semaphore [x] servant [x] serverless [x] service-layer [x] service-locator [x] singleton [x] spatial-partition [x] specification [x] state [x] step-builder [x] strategy [x] template-method [x] thread-pool [x] throttling [x] tls [x] tolerant-reader [x] trampoline [x] twin [x] typeobjectpattern [x] unit-of-work [x] value-object [x] visitor

    type: enhancement info: good first issue type: refactoring 
    opened by iluwatar 25
  • Lock Pattern #71: Added mutex and semaphore modules to demonstrate locks

    Lock Pattern #71: Added mutex and semaphore modules to demonstrate locks

    Added two modules to demonstrate locks.

    Mutex demonstrates a simple mutual exclusion lock. This is a binary lock which only allows one thread at a time to access the resource. See: Locks on Wikipedia

    Semaphore demonstrates a semaphore for controlling access to a pool of resources. See Semaphores on Wikipedia

    The main class of both programs is App.java.

    I haven't created any documentation yet. Let me know if you want any changes or need some explanations of the code, etc.

    status: under review 
    opened by gwildor28 25
  • Java 11 support: Start using var

    Java 11 support: Start using var

    This task is part of the Java 11 transition plan https://github.com/iluwatar/java-design-patterns/wiki/16.-Java-11-Transition

    Start using local-variable type inference (var). It is a nice example of syntactic sugar that helps reduce boilerplate code (see https://www.infoq.com/articles/upgrading-java-8-to-12/ and https://winterbe.com/posts/2018/09/24/java-11-tutorial/)

    It's a huge task to do this for all the patterns at once so it is possible to create pull requests for individual patterns. This way we can complete the task gradually. The following checklist tracks which patterns have already been refactored.

    [x] abstract-document [x] abstract-factory [x] acyclic-visitor [x] adapter [x] aggregator-microservices [x] ambassador [x] api-gateway [x] async-method-invocation [x] balking [x] bridge [x] builder [x] business-delegate [x] bytecode [x] caching [x] callback [x] chain [x] circuit-breaker [x] collection-pipeline [x] command [x] commander [x] composite [x] converter [x] cqrs [x] dao [x] data-bus [x] data-locality [x] data-mapper [x] data-transfer-object [x] decorator [x] delegation [x] dependency-injection [x] dirty-flag [x] double-checked-locking [x] double-dispatch [x] eip-aggregator [x] eip-message-channel [x] eip-publish-subscribe [x] eip-splitter [x] eip-wire-tap [x] event-aggregator [x] event-asynchronous [x] event-driven-architecture [x] event-queue [x] event-sourcing [x] execute-around [x] extension-objects [x] facade [x] factory-kit [x] factory-method [x] feature-toggle [x] fluentinterface [x] flux [x] flyweight [x] front-controller [x] guarded-suspension [x] half-sync-half-async [x] hexagonal [x] intercepting-filter [x] interpreter [x] iterator [x] layers [x] lazy-loading [x] leader-election [x] marker [x] master-worker-pattern [x] mediator [x] memento [x] model-view-controller [x] model-view-presenter [x] module [x] monad [x] monostate [x] multiton [x] mute-idiom [x] mutex [x] naked-objects [x] null-object [x] object-mother [x] object-pool [x] observer [x] page-object [x] partial-response [x] pipeline [x] poison-pill [x] priority-queue [x] private-class-data [x] producer-consumer [x] promise [x] property [x] prototype [x] proxy [x] queue-load-leveling [x] reactor [x] reader-writer-lock [x] repository [x] resource-acquisition-is-initialization [x] retry [x] role-object [x] semaphore [x] servant [x] serverless [x] service-layer [x] service-locator [x] singleton [x] spatial-partition [x] specification [x] state [x] step-builder [x] strategy [x] template-method [x] thread-pool [x] throttling [x] tls [x] tolerant-reader [x] trampoline [x] twin [x] typeobjectpattern [x] unit-of-work [x] value-object [x] visitor

    type: enhancement info: good first issue 
    opened by iluwatar 24
  • SonarQube reports code smells

    SonarQube reports code smells

    Java Design Patterns is analyzed with SonarQube.com static analysis. The analysis shows some blocker level code smells that should be fixed:

    https://sonarqube.com/component_issues/index?id=com.iluwatar%3Ajava-design-patterns#resolved=false|severities=BLOCKER|types=CODE_SMELL

    type: bug info: good first issue 
    opened by iluwatar 23
  • Hexagonal blog

    Hexagonal blog

    This is a pull request for a blog post about Hexagonal Architecture. The code samples have been embedded using gist-it. Looking forward to your comments.

    status: under review 
    opened by iluwatar 23
  • Event-carried state transfer pattern

    Event-carried state transfer pattern

    Event-carried state transfer (ECST) is a software design pattern that allows communication between different components or services in a distributed system by transferring state information along with events. It is often used in event-driven architectures, where events are generated by one component and consumed by another.

    In ECST, the state of a system is represented by the data that is carried with an event as it is transmitted from one component to another. When a component generates an event, it includes the current state of the system in the event payload. The consuming component can then use this state information to update its own internal state and process the event. This allows different components to communicate and share state information without the need for explicit requests or responses.

    ECST can be a useful pattern for building scalable and resilient distributed systems, as it allows components to operate independently and asynchronously. It can also make it easier to add new components or services to a system, as they can simply consume and process events without needing to be directly connected to other components.

    Links:

    • http://www.nicodewet.com/2019/03/20/name-your-event-driven-architecture-design-patterns.html
    • https://www.youtube.com/watch?v=gX0DUO171jc

    Acceptance criteria

    • ECST pattern example implemented
    info: help wanted epic: pattern type: feature 
    opened by javatlacati 0
  • build(deps): bump spring-boot-dependencies from 2.7.5 to 3.0.1

    build(deps): bump spring-boot-dependencies from 2.7.5 to 3.0.1

    Bumps spring-boot-dependencies from 2.7.5 to 3.0.1.

    Release notes

    Sourced from spring-boot-dependencies's releases.

    v3.0.1

    :lady_beetle: Bug Fixes

    • Fix typo in LocalDevToolsAutoConfiguration logging #33615
    • No warning is given when <springProfile> is used in a Logback <root> block #33610
    • Auto-configure PropagationWebGraphQlInterceptor for tracing propagation #33542
    • WebClient instrumentation fails with IllegalArgumentException when adapting to WebClientExchangeTagsProvider #33483
    • Reactive observation auto-configuration does not declare order for WebFilter #33444
    • Web server fails to start due to "Resource location must not be null" when attempting to use a PKCS 11 KeyStore #33433
    • Actuator health endpoint for neo4j throws NoSuchElementException and always returns Status.DOWN #33428
    • Anchors in YAML configuration files throw UnsupportedOperationException #33404
    • ZipkinRestTemplateSender is not customizable #33399
    • AOT doesn't work with Logstash Logback Encoder #33387
    • Maven process-aot goal fails when release version is set in Maven compiler plugin #33382
    • DependsOnDatabaseInitializationPostProcessor re-declares bean dependencies at native image runtime #33374
    • @SpringBootTest now throws a NullPointerException rather than a helpful IllegalStateException when @SpringBootConfiguration is not found #33371
    • bootBuildImage always trys to create a native image due to bootJar always adding a META-INF/native-image/argfile to the jar #33363

    :notebook_with_decorative_cover: Documentation

    • Improve gradle plugin tags documentation #33617
    • Improve maven plugin tags documentation #33616
    • Fix typo in tomcat accesslog checkExists doc #33512
    • Documented Java compiler level is wrong #33505
    • Fix typo in documentation #33453
    • Update instead of replace environment in bootBuildImage documentation #33424
    • Update the reference docs to document the need to declare the native-maven-plugin when using buildpacks to create a native image #33422
    • Document that the shutdown endpoint is not intended for use when deploying a war to a servlet container #33410
    • Reinstate GraphQL testing documentaion #33407
    • Description of NEVER in Sanitize Sensitive Values isn't formatted correctly #33398

    :hammer: Dependency Upgrades

    • Upgrade to AspectJ 1.9.19 #33586
    • Upgrade to Byte Buddy 1.12.20 #33587
    • Upgrade to Couchbase Client 3.4.1 #33588
    • Upgrade to Dropwizard Metrics 4.2.14 #33589
    • Upgrade to Elasticsearch Client 8.5.3 #33590
    • Upgrade to Hibernate 6.1.6.Final #33591
    • Upgrade to HttpClient 4.5.14 #33592
    • Upgrade to HttpCore 4.4.16 #33593
    • Upgrade to Infinispan 14.0.4.Final #33594
    • Upgrade to Jaybird 4.0.8.java11 #33595
    • Upgrade to Jetty 11.0.13 #33596
    • Upgrade to jOOQ 3.17.6 #33597
    • Upgrade to Kotlin 1.7.22 #33598
    • Upgrade to Lettuce 6.2.2.RELEASE #33599
    • Upgrade to MongoDB 4.8.1 #33600
    • Upgrade to MSSQL JDBC 11.2.2.jre17 #33601
    • Upgrade to Native Build Tools Plugin 0.9.19 #33602

    ... (truncated)

    Commits
    • 837947c Release v3.0.1
    • 5929d95 Merge branch '2.7.x'
    • b10b788 Next development version (v2.7.8-SNAPSHOT)
    • f588793 Update copyright year of changed files
    • 0254619 Merge branch '2.7.x'
    • e4772cf Update copyright year of changed files
    • 2e7ca6f Warning if <springProfile> is used in phase 2 model elements
    • 2ed512d Use model.deepMarkAsSkipped in SpringProfileModelHandler
    • 532fed3 Increase couchbase connection timeout for tests
    • 9562a2c Merge branch '2.7.x'
    • Additional commits viewable in compare view

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    epic: dependencies 
    opened by dependabot[bot] 1
  • Upgrade to Spring Boot 3.x

    Upgrade to Spring Boot 3.x

    Spring Boot has recently released 3.x. In this task we are going to upgrade the dependency. There is a helpful migration guide available here: https://github.com/spring-projects/spring-boot/wiki/Spring-Boot-3.0-Migration-Guide

    Acceptance criteria

    • Spring Boot upgraded to 3.x
    epic: dependencies 
    opened by iluwatar 2
  • Code snippet of **_<org.apache.commons.logging.LogFactory: org.apache.commons.logging.LogFactory getFactory()>_** in _**org.slf4j:jcl-over-slf4j:jar:1.7.16:compile**_ (loaded version):

    Code snippet of **__** in _**org.slf4j:jcl-over-slf4j:jar:1.7.16:compile**_ (loaded version):

        Code snippet of **_<org.apache.commons.logging.LogFactory: org.apache.commons.logging.LogFactory getFactory()>_** in _**org.slf4j:jcl-over-slf4j:jar:1.7.16:compile**_ (loaded version):
    

    01

    Code snippet of <org.apache.commons.logging.LogFactory: org.apache.commons.logging.LogFactory getFactory()> in commons-logging:commons-logging:jar:1.2:compile (shadowed but expected to invoke method): 02 .......

    As a result, these conflicting method included in commons-logging:commons-logging:jar:1.2:compile deals with different cases, which changes the control flows and data flows. So being forced to use these methods in org.slf4j:jcl-over-slf4j:jar:1.7.16:compile may lead to inconsisitent semantic behaviors.

    Originally posted by @HelloCoCooo in https://github.com/iluwatar/java-design-patterns/issues/868#issuecomment-480587255

    epic: dependencies type: refactoring 
    opened by vangirja 3
  • Java 17: Start using records

    Java 17: Start using records

    Available since Java 16, we can now use the record type for immutable classes. It's well described at https://dzone.com/articles/what-are-java-records

    Acceptance criteria

    • The repository code has been refactored to use the record type
    info: help wanted type: refactoring epic: code quality 
    opened by iluwatar 1
Owner
Ilkka SeppΓ€lΓ€
Ilkka SeppΓ€lΓ€
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