Browse free open source Java Frameworks and projects below. Use the toggles on the left to filter open source Java Frameworks by OS, license, language, programming language, and project status.

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  • 1
    Whole Platform
    The Whole Platform is a technology for engineering the production of software. We provide an Eclipse based Language Workbench for developing, manipulating and transforming languages using a model driven approach.
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    Downloads: 206 This Week
    Last Update:
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  • 2
    SW Test Automation Framework
    The Software Testing Automation Framework (STAF) is a framework designed to improve the level of reuse and automation in test cases and test environments. The goal of STAF is to provide a complete end-to-end automation solution for testers.
    Downloads: 35 This Week
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  • 3
    reacTIVision
    reacTIVision is a computer vision framework for the fast and robust tracking of markers attached on physical objects, and the creation of multi-touch surfaces. It was designed for the rapid development of table-based tangible user interfaces.
    Downloads: 34 This Week
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  • 4
    Netty

    Netty

    An event-driven asynchronous network application framework

    Netty is an asynchronous, event-driven networking framework for the JVM that simplifies building high-performance clients and servers. It wraps Java NIO with a channel/handler pipeline model, enabling clean composition of codecs, TLS, and application logic with minimal overhead. Its ByteBuf abstractions, buffer pooling, and zero-copy techniques help reduce GC pressure and improve throughput under heavy I/O. Support for common protocols—HTTP/1.1, HTTP/2, WebSocket, and raw TCP/UDP—makes it a foundation for RPC frameworks, proxies, and messaging systems. Pluggable transports and native integrations (like epoll or kqueue where available) allow fine-tuning for different operating systems. With robust resource management, leak detection, and extensive testing, Netty is widely chosen when low latency, scalability, and control over the I/O stack are required.
    Downloads: 7 This Week
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  • 5
    tinylog

    tinylog

    tinylog is a lightweight logging framework for Java, Kotlin, Scala

    Simplify your logging with tinylog. The lightweight logging framework can be used with Java, Kotlin, Scala, and any other JVM language. tinylog is open source and runs wherever Java is used: JVM, GraalVM, and Android.
    Downloads: 7 This Week
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  • 6

    OpenXava

    Automatic frontend engine for Java

    Automatic frontend engine for Java. Write just the domain classes in plain Java. Get a web application ready for production.
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    Downloads: 31 This Week
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  • 7
    Bytecoder

    Bytecoder

    Framework to interpret and transpile JVM bytecode to JavaScript

    Bytecoder is a Rich Domain Model for Java Bytecode and Framework to interpret and transpile it to other languages such as JavaScript, OpenCL or WebAssembly. The JVM Bytecode is parsed and transformed into an intermediate representation. This intermediate representation is passed thru optimizer stages and sent to a backend implementation for target code generation. The JavaScript backend transforms the intermediate representation into JavaScript.
    Downloads: 6 This Week
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  • 8
    CTFcrackTools

    CTFcrackTools

    China's first CTFTools framework

    The first CTF tool framework in China. China's first CTFTools framework designed to help CTFer quickly overcome the CTF problem. Use kotlin and java mixed development. This is probably the first tool framework applied to CTF in China. Built-in current mainstream password, includes but is not limited to Virginia password, Caesar password, fence password. Users can write plugs independently, but only support Python to write plugs. The writing method is also extremely simple. (Due to Jython's own reasons, he was temporarily unable to support Python3) When introducing plugs, remember to confirm that the jython file has been loaded. The project has been enhanced. This replacement only retains some of the core codes and reconstructs UI and optimized codes to make this framework support more functions.
    Downloads: 6 This Week
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  • 9
    Habitica for Android

    Habitica for Android

    Native Android app for Habitica

    Habitica is an open source habit building program which treats your life like a Role Playing Game. Level up as you succeed, lose HP as you fail, earn money to buy weapons and armor. This repository is related to the Android Native Application.
    Downloads: 6 This Week
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  • 10
    Litemall

    Litemall

    litemall = Spring Boot

    Litemall is a lightweight e-commerce system built with Spring Boot, MyBatis, and Vue.js, designed for small and medium-sized online retail platforms. It provides a full-featured backend management interface along with customer-facing mobile and web portals. Litemall supports common e-commerce features such as product catalog, order processing, payment integration, user management, and statistical analysis, making it easy to customize and deploy a standalone online store.
    Downloads: 6 This Week
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  • 11
    Mockito

    Mockito

    Most popular Mocking framework for unit tests written in Java

    Mockito downloads and instructions for setting up Maven, Gradle and other build systems are available from the Central Repository and Bintray. Mockito 3.x requires Java 8, but otherwise doesn’t introduce any breaking changes compared to the 2.x series. Mockito 2.25.0 had an important feature added for anyone using mockito-inline. In particular anyone using Kotlin (which demands using mockito-inline) and PowerMock (which exacerbates the problem even more) will want to add this to all of their test classes to avoid a large memory leak. Fancy getting world-wide visibility and building up an eternal fame of an OSS contributor? Use the latest version! Hack and experiment. Speak up at the mailing list. Mockito is a mocking framework that tastes really good. It lets you write beautiful tests with a clean & simple API. Mockito doesn’t give you hangover because the tests are very readable and they produce clean verification errors.
    Downloads: 6 This Week
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  • 12
    Netty-socketio

    Netty-socketio

    Socket.IO server implemented on Java

    This project is an open-source Java implementation of Socket.IO server. Based on Netty server framework. Supports 0.7...0.9.16 (netty-socketio 1.6.6) and 1.0+ (netty-socketio latest version) version of Socket.IO-client. Supports distributed broadcast across netty-socketio nodes (Redisson, Hazelcast). Supports OSGi, supports Spring, lock-free and thread-safe implementation, and declarative handler configuration via annotations. YourKit is kindly supporting this open source project with its full-featured Java Profiler. YourKit, LLC is the creator of innovative and intelligent tools for profiling Java and .NET applications. CentOS, 1 CPU, 4GB RAM runned on VM, CPU 10%, Memory 15%, 6000 xhr-long polling sessions or 15000 websockets sessions, 4000 messages per second.
    Downloads: 6 This Week
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  • 13
    Transmittable ThreadLocal

    Transmittable ThreadLocal

    Provides an enhanced InheritableThreadLocal

    TransmittableThreadLocal (TTL), the missing Java™ std lib(simple & 0-dependency) for framework/middleware, provide an enhanced InheritableThreadLocal that transmits values between threads even using thread pooling components. In the case of using thread pools and other execution components that will pool multiple threads, the ThreadLocalvalue transfer function is provided to solve the problem of context transfer during asynchronous execution. A Javastandard library should provide standard capabilities for framework/middleware facility development. ThreadLocalThe demand scenario is TransmittableThreadLocalthe potential demand scenario. If your business needs to "pass ThreadLocalvalues ​​in the case of using thread pools and other execution components that will pool multiple threads ", it is the TransmittableThreadLocaltarget scenario.
    Downloads: 6 This Week
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  • 14
    WebMagic

    WebMagic

    A scalable web crawler framework for Java

    WebMagic is a scalable crawler framework. It covers the whole lifecycle of crawler, downloading, url management, content extraction and persistent. It can simplify the development of a specific crawler. WebMagic is a simple but scalable crawler framework. You can develop a crawler easily based on it. WebMagic has a simple core with high flexibility, a simple API for html extracting. It also provides annotation with POJO to customize a crawler, and no configuration is needed. Some other features include the fact that it is multi-thread and has distribution support. WebMagic is very easy to integrate. Add dependencies to your pom.xml. WebMagic use slf4j with slf4j-log4j12 implementation. If you customized your slf4j implementation, please exclude slf4j-log4j12. You can write a class implementation of PageProcessor.
    Downloads: 6 This Week
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  • 15
    Webcam Capture API

    Webcam Capture API

    Allow integrated or USB-connected webcams to be accessed from Java

    This library allows you to use your built-in or external webcam directly from Java. It's designed to abstract commonly used camera features and support various capturing frameworks. Assume a situation when your code depends on some capturing framework, but suddenly you have to drop it and use a different, maybe newer one (e.g. replace archaic JMF with newest GStreamer). By doing this you will have to rewrite significant piece of your code because these frameworks are completely different and not compatible at all. This is where Webcam Capture API comes to save the world - it was created to remove the burden of such situations so you do not have to rewrite your code ever again, but instead, you can simply switch the driver class to a different one.
    Downloads: 6 This Week
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  • 16
    Prowide Core

    Prowide Core

    Java framework for SWIFT [tm] MT (FIN) messaging

    Prowide Core (previously known as WIFE) is an open source Java framework for managing SWIFT MT messages. The library key features are the comprehensive Java model for all MT message types, along a straight-forward parsing and building API. The project is active since 2006, production ready and commercially supported. For detail information on the support package options please check: https://www.prowidesoftware.com/services SWIFT is a trademark of S.W.I.F.T. SCRL. (www.swift.com) Prowide in GitHub: https://github.com/prowide
    Downloads: 45 This Week
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  • 17
    IKVM.NET is a JVM for the Microsoft .NET Framework and Mono. It can both dynamically run Java classes and can be used to convert Java jars into .NET assemblies. It also includes a port of the OpenJDK class libraries to .NET.
    Downloads: 23 This Week
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  • 18
    Eclipse 4diac

    Eclipse 4diac

    Eclipse 4diac the open source solution for industrial automation

    Eclipse 4diac is an open source PLC environment allowing to implement industrial control solutions in a vendor neutral way. 4diac implements IEC 61499 extending IEC 61131-3 with improved support for controller to controller communication and dynamic reconfiguration. With that 4diac provides the infrastructure for Industrie 4.0 and industrial IoT. Further information and the latest versions can be found here: https://eclipse.dev/4diac/
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    Downloads: 31 This Week
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  • 19
    Codename One

    Codename One

    Cross-platform framework for building truly native mobile apps

    An open-source mobile-first toolkit for building high-quality, cross-platform native apps for Android, iOS, Desktop & Web. Rapid cross-platform app development using Java or Kotlin with 100% code reuse. Apps are compiled down to native code for maximum performance and a smooth user experience. Write, debug, and test apps all inside your IDE (IntelliJ, Eclipse, VSCode or NetBeans) using the Codename One simulator. One-click for app-store-ready device builds, without the headache of maintaining native SDKs. Build beautiful UI with Codename One’s rich set of widgets, specifically designed for mobile apps. Native look and feel out of the box, but fully themeable using CSS to provide your own unique look. Compiles Java or Kotlin into native code for iOS, UWP (Universal Windows Platform), Android and even JavaScript (with seamless PWA and Thread support) Changes you make in your Java/Kotlin source code will be applied immediately to your already-running app in the simulator.
    Downloads: 5 This Week
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  • 20
    Talon for Twitter

    Talon for Twitter

    The Holo version of my popular Android Talon for Twitter app

    This is the complete version of the Twitter client that I created for Android. It is 100% open source, the only thing that you will have to do plug in is your own API keys. Feel free to use this as a resource for those kinds of thing, that's one of the reasons I wanted to open source it in the first place. Lots to learn from a big project like this, and I think that is pretty important with the ever changing world of Android.
    Downloads: 5 This Week
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  • 21
    Vaadin Framework

    Vaadin Framework

    Vaadin 6, 7, 8 is a Java framework for modern Java web applications

    Vaadin is a web app development framework for Java that includes a large library of UI components. It helps you build reliable web apps and a great UX faster than before. Building an enterprise web app involves a lot of moving pieces. Vaadin simplifies the process with an integrated web app development platform for Java backends. Vaadin comes with all the UI components, frameworks, and tools you need to build a reliable, secure, app with great UX. Research shows that good user experience (UX) increases employee engagement, helps digital transformations to succeed, and avoids costly mistakes. The Vaadin Design System provides UI components and UX patterns that help you build consistently good user experiences in every app. Better yet, you can use it to build a custom design system for your organization. Vaadin comes with 45+ UI components that help you build consistent UIs fast. The theme can be customized to match your brand.
    Downloads: 5 This Week
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  • 22
    Development of this library has been moved to https://github.com/kordamp/json-lib/ Json-lib is a java library for transforming beans, maps, collections, java arrays and XML to JSON and back again to beans and DynaBeans. It is based on the work by Douglas Crockford in http://www.json.org/java.
    Downloads: 26 This Week
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  • 23
    Discovery

    Discovery

    Nepxion Discovery is a solution for Spring Cloud

    Nepxion Discovery is a solution for Spring Cloud with blue green, gray, route, blacklist, limitation, circuit breaker, degrade, isolation, monitor, tracing, dye, failover, async agent. Only one or more services are upgraded at a time, the upgrade is completed and monitored and observed, and this process is performed continuously until all the old versions in the cluster are upgraded to the new version. In the process of stopping the old version, it is impossible to accurately calculate whether the old version has completed the work it is performing, and it needs to be judged by the business itself. Full-link custom gateways, service filters, and load balancing strategies trigger blue-green grayscale release. Full link local and remote, local and global non-parameterized rule-driven strategy. Full-link blue-green-gray release scheduling modeling and traffic detection.
    Downloads: 4 This Week
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  • 24
    Eclipse Collections

    Eclipse Collections

    Eclipse Collections is a collections framework for Java

    Eclipse Collections is the best Java collections framework ever that brings happiness to your Java development. Integrate it to your codebase today with your favorite build tools! Maximize the power of Java 8 Lambda expressions and method references with rich APIs directly available on your collections. Many container types include immutable collections, primitive collections, bimaps, multimaps and bags. You can make use of various container types, leveraging handy factory methods for instantiation. Eclipse Collections provides a memory-efficient implementation of Sets and Maps as well as primitive collections. Check out the Eclipse Collections Kata, a fun way to help you learn idiomatic Eclipse Collections usage. This particular kata is set up as a series of unit tests that fail. Your task is to make them pass, using Eclipse Collections.
    Downloads: 4 This Week
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  • 25
    JetCache

    JetCache

    JetCache is a Java cache framework

    JetCache is a Java cache abstraction that provides uniform usage for different caching solutions. It provides more powerful annotations than those in Spring Cache. The annotations in JetCache support native TTL, two-level caching, and automatically refresh in distributed environments, also you can manipulate Cache instances by your code. Currently, there are four implementations: RedisCache, TairCache(not open source on github), CaffeineCache (in memory) and a simple LinkedHashMapCache (in memory).
    Downloads: 4 This Week
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