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
    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: 42 This Week
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  • 2
    Arianne RPG

    Arianne RPG

    Arianne is an engine to develop multiplayer online games like Stendhal

    Arianne is a multiplayer online engine to develop turn based and real time games, providing a simple way of creating the game server rules and clients like our MORPG Stendhal. Our engine Marauroa uses Java and SQL for hosting hundreds of players on a solo host. Stendhal is a fun friendly and free multiplayer online adventure game with a huge and rich world. With hundreds of NPCs and different quests, features like the Travel log and achievement system keep track of progress. Thousands of creatures are ready to fight, above and below ground, and as players level up they can compare themselves on a detailed stats website. The engine Marauroa provides a simple way of creating games on a portable and robust server architecture. Marauroa manages the client server communication and provides an object orientated view of the world for game developers. It handles database access in a transparent way to store player accounts, character progress and the state of the world
    Downloads: 43 This Week
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  • 3
    Hawtio

    Hawtio

    Hawtio web console helps you manage your JVM stuff and stay cool

    Hawtio is a lightweight and modular Web console for managing Java applications. Hawtio has plugins such as: Apache Camel and JMX (Logs, Spring Boot, Quartz, and more will be provided soon). You can dynamically extend Hawtio with your own plugins or automatically discover plugins inside the JVM. The only server-side dependency (other than the static HTML/CSS/JS/images) is the excellent Jolokia library which has a small footprint (around 300KB) and is available as a JVM agent or comes embedded as a servlet inside the hawtio-default.war.
    Downloads: 9 This Week
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  • 4
    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: 9 This Week
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  • 5
    jimmer

    jimmer

    A revolutionary ORM framework for both java and kotlin.

    A revolutionary ORM framework for both Java and kotlin and a complete integrated solution. You can view everything from the documentation. Brings dynamism into static language ORM frameworks, achieving flexible capabilities for operating on complex dynamic data structures without compromising the complete compile-time safety checks of static languages, eliminating DTO explosion and unafraid of engineering expansion and changing requirements. Its innovative SQL DSL supports dynamic table joins and native SQL embedding, gracefully handling real-world complexity. Focuses on business and reaping caching gains. CDC solutions decoupled from specific caching technologies are transparent to business code. Requires no special prior knowledge - veterans of any ORM can quickly and painlessly migrate. The learning curve is scientifically friendly, serving as a high-quality reference for new learners of ORM usage.
    Downloads: 9 This Week
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  • 6
    testng

    testng

    TestNG testing framework

    TestNG is a testing framework inspired from JUnit and NUnit but introduces some new functionalities that make it more powerful and easier to use. Run your tests in arbitrarily big thread pools with various policies available (all methods in their own thread, one thread per test class, etc...).
    Downloads: 9 This Week
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  • 7
    Fury

    Fury

    A blazing fast multi-language serialization framework

    Fury is a blazing-fast multi-language serialization framework powered by jit(just-in-time compilation) and zero-copy, providing up to 170x performance and ultimate ease of use. Based on efficient JIT, struct deserialization can get 170x speed up compared to other serialization frameworks. In serialization scenarios, Fury can achieve a 100x speed up compared to traditional serialization frameworks. If you use Java clusters on a large scale, this will save a lot of computing resources.
    Downloads: 6 This Week
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  • 8
    Seata

    Seata

    An easy-to-use, high-performance distributed transaction solution

    Seata, or Simple Extensible Autonomous Transaction Architecture is an open source distributed transaction solution that brings high performance and easy-to-use distributed transaction services under a microservices architecture. It has 3 basic components: a Transaction Coordinator for maintaining the status of global and branch transactions; a Transaction Manager that defines the scope of global transaction; and a Resource Manager that manages resources being worked on by branch transactions, and drives branch transaction commit or rollback. Seata has played a pivotal role of distributed consistency Middleware in Ali economy, and has provided strong support for businesses of all departments. It continues to be used and trusted by dozens of other companies.
    Downloads: 6 This Week
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  • 9
    Spring Batch

    Spring Batch

    Spring Batch is a framework for writing batch applications using Java

    A lightweight, comprehensive batch framework designed to enable the development of robust batch applications vital for the daily operations of enterprise systems. Spring Batch provides reusable functions that are essential in processing large volumes of records, including logging/tracing, transaction management, job processing statistics, job restart, skip, and resource management. It also provides more advanced technical services and features that will enable extremely high-volume and high performance batch jobs through optimization and partitioning techniques. Simple as well as complex, high-volume batch jobs can leverage the framework in a highly scalable manner to process significant volumes of information.
    Downloads: 6 This Week
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  • 10
    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: 36 This Week
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  • 11
    SIGAR (System Information Gatherer and Reporter) is a cross-platform, cross-language library and command-line tool for accessing operating system and hardware level information in Java, Perl and .NET.
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    Downloads: 47 This Week
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  • 12
    Simple Binary Encoding (SBE)

    Simple Binary Encoding (SBE)

    Simple Binary Encoding (SBE) - High Performance Message Codec

    SBE is an OSI layer 6 presentation for encoding and decoding binary application messages for low-latency financial applications. This repository contains the reference implementations in Java, C++, Golang, C#, and Rust. More details on the design and usage of SBE can be found on the Wiki. An XSD for SBE specs can be found here. Please address questions about the specification to the SBE FIX community. For the latest version information and changes see the Change Log with downloads at Maven Central. The Java and C++ SBE implementations work very efficiently with the Aeron messaging system for low-latency and high-throughput communications. The Java SBE implementation has a dependency on Agrona for its buffer implementations.
    Downloads: 5 This Week
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  • 13
    jooby

    jooby

    The modular web framework for Java and Kotlin

    Jooby is a modern, performant and easy to use web framework for Java and Kotlin built on top of your favorite web server.
    Downloads: 5 This Week
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  • 14
    WebHarvest - web data extraction tool
    Web data extraction (web data mining, web scraping) tool. It leverages well proved XML and text processing techologies in order to easely extract useful data from arbitrary web pages.
    Downloads: 30 This Week
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  • 15

    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: 19 This Week
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  • 16
    Besu Ethereum Client

    Besu Ethereum Client

    An enterprise-grade Java-based, Apache 2.0 licensed Ethereum client

    You can use Besu to develop enterprise applications requiring secure, high-performance transaction processing in a private network. A private network is a network not connected to Ethereum Mainnet or an Ethereum testnet. Private networks typically use a different chain ID and proof of authority consensus (QBFT, IBFT 2.0, or Clique). You can also create a local development network using proof of work (Ethash). Instructions for how to get started with developing on the Besu codebase. Please also read the wiki for more details on how to submit a pull request (PR). Besu is an Apache 2.0 licensed, MainNet compatible, Ethereum client written in Java. Participation in private networks is typically restricted in some way, so the volume of traffic is much lower than on Mainnet, resulting in lower system requirements. Depending on your environment and network setup, the minimum Java Virtual Machine (JVM) memory requirement for private networks is 4 GB.
    Downloads: 4 This Week
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  • 17
    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: 4 This Week
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  • 18
    OfficeFloor

    OfficeFloor

    inversion of coupling control

    OfficeFloor provides inversion of coupling control, with its: - dependency injection - continuation injection - thread injection For more information visit the OfficeFloor web site ( http://officefloor.net )
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    Downloads: 103 This Week
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  • 19
    Niagara AX Community Modules
    A library of modules for the Tridium Niagara AX platform. AX programmers are encouraged to use and expand the library.
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    Downloads: 34 This Week
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  • 20
    Colorer Library
    Colorer provides source text syntax highlighting services. It colorizes source codes in editor systems (more than 200 syntaxes). Uses powerful HRC format(XML, RE, context free grammas), allowing to support any language. Available as Eclipse plugin.
    Downloads: 21 This Week
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  • 21
    SoundHelix

    SoundHelix

    Versatile algorithmic random music generation software written in Java

    SoundHelix is a free versatile Java framework for algorithmic random music composition. SoundHelix can generate random songs, play them (for example, on any number of MIDI devices or MIDI-capable software synthesizers) and is highly customizable using XML configuration. SoundHelix also allows writing the generated music as MIDI files. SoundHelix produces music that is actually enjoyable to listen to.
    Downloads: 23 This Week
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  • 22
    Apache Shiro

    Apache Shiro

    Apache Shiro

    Apache Shiro is a powerful and easy-to-use Java security framework that performs authentication, authorization, cryptography, and session management. With Shiro’s easy-to-understand API, you can quickly and easily secure any application, from the smallest mobile applications to the largest web and enterprise applications.
    Downloads: 3 This Week
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  • 23
    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: 3 This Week
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  • 24
    FolioReader

    FolioReader

    A Java ePub reader and parser framework for Android

    FolioReader-Android is an EPUB reader written in Java and Kotlin.
    Downloads: 3 This Week
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  • 25
    JBot

    JBot

    Make Slack and Facebook Bots in Java

    JBot is a java framework (inspired by Howdyai's Botkit) to make Slack and Facebook bots in minutes. It provides all the boilerplate code needed so that you can make your bot live right away. Provides you with all the boilerplate code which handles underlying WebSocket connections and other complexities. Supports extra events in addition to all the events supported by Slack/Facebook which makes your work a lot easier. Receiving & sending messages is as easy as defining a @Controller and calling reply(). The conversation feature of JBoss makes talking to your bot a breeze. This feature makes JBot different from than rest of the Java frameworks out there.
    Downloads: 3 This Week
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