ai-agent

Java Design Patterns

Name: Java Design Patterns
Author: iluwatar

Design patterns implemented in Java

94,595 stars27,410 forksJavaUpdated 7/31/2026100% free · open source

What it does

Provides a comprehensive collection of Java design patterns, allowing developers to learn and implement proven solutions to common software design problems

Install / run

git clone https://github.com/iluwatar/java-design-patterns.git

When to use it

•When building complex software systems and wanting to apply well-established design principles
•When trying to solve a specific software design problem and looking for a proven solution
•When learning Java and wanting to understand how to apply design patterns in real-world applications

Quick start

1Explore the `design-patterns` directory to see the different patterns implemented, such as `creational`, `structural`, and `behavioral`
2Open the `README.md` file to see an overview of the project and its contents
3Run the `mvn clean install` command to build and install the project
4Use an IDE like Eclipse or IntelliJ to import the project and start exploring the code
5Start with the `src/main/java/com/iluwatar/designpatterns` package to see the implementation of different design patterns

Ready-to-paste prompt

Explore the `FactoryMethodPattern` class in the `com/iluwatar/designpatterns/creational/factorymethod` package to see how to implement the Factory Method design pattern

Heads up: Make sure you have Maven installed and configured properly on your system, as the project uses Maven for build and dependency management

Saves to your device

Topics

awesome-list

design-patterns

hacktoberfest

java

principles

snippets

snippets-collection

snippets-library

How Java Design Patterns works

Codeflow

Free to inspect

Java Design Patterns is a very large Java project (~87k lines across 1357 code files, plus 637 test files). It is a full software project: use it through its install path rather than reading it end to end. Last commit this month, Other license, has a test suite.

Size

Very large codebase

~87k lines · 1357 code files · days to read — use, don't read

Setup

Developer setup

A real software project. Use it via its install path; don't expect to read it all.

Runs on

Java/JVM

No API keys detected

Java 99%

What happens, step by step

Design patterns implemented in Java