Java Java

Open-source Java projects categorized as Java

Top 23 Java Java Projects

  • GitHub repo JavaGuide

    「Java学习+面试指南」一份涵盖大部分 Java 程序员所需要掌握的核心知识。准备 Java 面试,首选 JavaGuide!

    Project mention: Top 10 Developer Trends, Sun Oct 11 2020 | | 2020-10-11

    Snailclimb / JavaGuide

  • GitHub repo Design Patterns

    Design patterns implemented in Java

    Project mention: What is dependency injection? | | 2021-03-26

    Now, when I first saw the DI principle it didn't make any sense to me, so let's look at an example with a short trip to Middle Earth, using the same example found in this repository of Java design patterns.

  • GitHub repo Elasticsearch

    Free and Open, Distributed, RESTful Search Engine

    Project mention: Rsyslog kafka and elk | | 2021-04-04

    ## Default Elasticsearch configuration from Elasticsearch base image. ## # "docker-cluster" ## X-Pack settings ## see # xpack.license.self_generated.type: trial true xpack.monitoring.collection.enabled: true

  • GitHub repo Spring Boot

    Spring Boot

    Project mention: Steps to upgrade spring-boot 1.x to 2.x | | 2021-04-13

    Spring-boot-2 related properties changes

  • GitHub repo advanced-java

    😮 Core Interview Questions & Answers For Experienced Java(Backend) Developers | 互联网 Java 工程师进阶知识完全扫盲:涵盖高并发、分布式、高可用、微服务、海量数据处理等领域知识

    Project mention: Top 10 Developer Trends, Mon Oct 12 2020 | | 2020-10-12

    doocs / advanced-java

  • GitHub repo interviews

    Everything you need to know to get the job. (by kdn251)

    Project mention: Free Computer Science Resources with Interview Prep and much more... | | 2021-03-29


  • GitHub repo RxJava

    RxJava – Reactive Extensions for the JVM – a library for composing asynchronous and event-based programs using observable sequences for the Java VM.

    Project mention: MVVM Architecture On HarmonyOS Using Retrofit And RxJava | | 2021-03-29
  • GitHub repo Guava

    Google core libraries for Java

    Project mention: Ask HN: 30 years old attempting a career change, advice needed | | 2021-04-11

    I haven’t written Java in my day-to-day for quite some time now, but the first thing that came to mind for a good open source Java codebase is Guava by Google:

    It’s a collection of core libraries for Java that I believe should have a lot of useful patterns/concepts to learn from.

    I also highly recommend Effective Java by Joshua Bloch ( An incredible text for any kind of programmer, and even better if you’re specifically interested in Java.

    Good luck!

  • GitHub repo OkHttp

    Square’s meticulous HTTP client for the JVM, Android, and GraalVM.

    Project mention: Spring boot | | 2021-03-20

    There are 3rd party HTTP clients like Apache HttpClient and OkHttp ( and

  • GitHub repo Retrofit

    A type-safe HTTP client for Android and the JVM

    Project mention: MVVM Architecture On HarmonyOS Using Retrofit And RxJava | | 2021-03-29


  • GitHub repo Java

    All Algorithms implemented in Java

    Project mention: Any beginner-friendly tutorials on hashing +salting strings? | | 2021-03-27

    here you can use of the ciphers

  • GitHub repo MPAndroidChart

    A powerful 🚀 Android chart view / graph view library, supporting line- bar- pie- radar- bubble- and candlestick charts as well as scaling, panning and animations.

    Project mention: Android UI templates for displaying charts of data coming from sensors? | | 2021-03-22
  • GitHub repo ZXing

    ZXing ("Zebra Crossing") barcode scanning library for Java, Android

    Project mention: Is there any way to use an object reference to fetch the object itself? | | 2021-03-24

    Have a look at ZXing or QRGen.

  • GitHub repo jadx

    Dex to Java decompiler

    Project mention: Task >[Run Shell] Action, Commands > Service. | | 2021-03-18

    There are ways, but for me, I find it easy to use the JADX since I can search anything and instantly go to the class it implements or use. It's really confusing to be honest haha. They use other classes to do this and that.

  • GitHub repo Arthas

    Alibaba Java Diagnostic Tool Arthas/Alibaba Java诊断利器Arthas

  • GitHub repo fastjson

    A fast JSON parser/generator for Java.

  • GitHub repo spring-boot-demo

    该项目已成功集成 actuator(监控)、admin(可视化监控)、logback(日志)、aopLog(通过AOP记录web请求日志)、统一异常处理(json级别和页面级别)、freemarker(模板引擎)、thymeleaf(模板引擎)、Beetl(模板引擎)、Enjoy(模板引擎)、JdbcTemplate(通用JDBC操作数据库)、JPA(强大的ORM框架)、mybatis(强大的ORM框架)、通用Mapper(快速操作Mybatis)、PageHelper(通用的Mybatis分页插件)、mybatis-plus(快速操作Mybatis)、BeetlSQL(强大的ORM框架)、upload(本地文件上传和七牛云文件上传)、redis(缓存)、ehcache(缓存)、email(发送各种类型邮件)、task(基础定时任务)、quartz(动态管理定时任务)、xxl-job(分布式定时任务)、swagger(API接口管理测试)、security(基于RBAC的动态权限认证)、SpringSession(Session共享)、Zookeeper(结合AOP实现分布式锁)、Ra

    Project mention: Top 10 Developer Trends, Sun Oct 11 2020 | | 2020-10-11

    xkcoding / spring-boot-demo

  • GitHub repo Selenium WebDriver

    A browser automation framework and ecosystem.

    Project mention: How would I go about creating a web scraper that returns info from the browser's console? | | 2021-04-07

    This should be doable with Selenium

  • GitHub repo libGDX

    Desktop/Android/HTML5/iOS Java game development framework

    Project mention: Some examples which use the minimalist 3D Game Engine Kotlin Multiplatform game engine I'm building: MiniGDX. I can deploy a game for the JVM, the Web and Android. | | 2021-04-11
  • GitHub repo Exoplayer

    An extensible media player for Android

    Project mention: Plex for Android v8.14.0 Released | | 2021-03-11

    As long as you provide a way to re-link a LGPL library upon request (statically linked or not), it's fine. GPL, AFAIK, won't allow this. Though honestly I'm very surprised the Plex clients are no longer open source. It's incredibly unfortunate. People would jump to improve it because we are tired of waiting. This was done with ExoPlayer, yet now it seems even when ExoPlayer supports the feature entirely, Plex on android will lag behind for several years.

  • GitHub repo Jenkins

    Jenkins automation server

    Project mention: Software developer wanting to dabble in homelabs. | | 2021-04-07

    Seems an application called Jenkins is used for the build server.

  • GitHub repo Redisson

    Redisson - Redis Java client with features of In-Memory Data Grid. Over 50 Redis based Java objects and services: Set, Multimap, SortedSet, Map, List, Queue, Deque, Semaphore, Lock, AtomicLong, Map Reduce, Publish / Subscribe, Bloom filter, Spring Cache, Tomcat, Scheduler, JCache API, Hibernate, MyBatis, RPC, local cache ...

NOTE: The open source projects on this list are ordered by number of github stars. The number of mentions indicates repo mentiontions in the last 12 Months or since we started tracking (Dec 2020). The latest post mention was on 2021-04-13.


What are some of the best open-source Java projects in Java? This list will help you:

Project Stars
1 JavaGuide 101,467
2 Design Patterns 65,037
3 Elasticsearch 54,416
4 Spring Boot 54,391
5 advanced-java 53,319
6 interviews 50,896
7 RxJava 44,431
8 Guava 40,770
9 OkHttp 39,729
10 Retrofit 37,849
11 Java 36,343
12 MPAndroidChart 33,072
13 ZXing 27,524
14 jadx 25,626
15 Arthas 25,304
16 fastjson 23,185
17 spring-boot-demo 21,229
18 Selenium WebDriver 20,498
19 libGDX 18,268
20 Exoplayer 17,509
21 Jenkins 17,133
22 Redisson 16,147
23 Apache Flink 15,920