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

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  • 1
    Hover

    Hover

    A floating menu library for Android

    Hover is an open source floating menu framework for Android, developed by Nest Labs (a Google company), designed to help developers integrate interactive, persistent floating menus into their mobile applications. It provides a complete out-of-the-box implementation for overlay menus that can expand, collapse, and dynamically update content without disrupting the main user interface. Hover’s architecture allows developers to easily customize behavior and appearance by extending its base classes such as HoverMenuService, HoverMenu, and HoverView. The framework also includes tools for managing hover menus as foreground services, improving compatibility with Android O and later versions. With support for direct instantiation via code or XML, Hover enables flexible integration into a variety of Android UI structures. While still in beta and subject to API changes, it offers a robust, modular foundation for creating multitasking-style floating interfaces in Android apps.
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  • 2
    This project contains many useful utility classes developed by the fine folks at Hyper9.
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  • 3
    A small set of tools for use with the Wicket web framework
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  • 4
    Hystrix

    Hystrix

    Latency and Fault Tolerance for Distributed Systems

    Defend your app with Hystrix, a latency and fault tolerance library developed by the Netflix API team. It works by isolating points of access to remote systems, services and 3rd party libraries, thereby stopping cascading failure and providing fallback options, and making complex distributed systems more resilient in cases where failure is inevitable. In a distributed environment, failure is simply inevitable for some service dependencies. With Hystrix you can control the interactions between these distributed services and protect your host application. Hystrix also allows you to fail fast and rapidly recover, fallback and gracefully degrade when possible, and monitor and control operations near real-time.
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  • 5
    Light library for easy translation of Java programs using annotations and reflection.
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  • 6

    IBController

    Interactive Brokers TWS / IB Gateway Host Tool

    IBController has MOVED TO GITHUB and is no longer available from this website. From April 29 2014 IBController is no longer hosted at SourceForge. It has been moved to GitHub and renamed to "IBC". The project home page is now at https://github.com/IbcAlpha/IBC You can download the latest version from https://github.com/IbcAlpha/IBC/releases/latest
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  • 7
    This Library provides a java API for firewall logs, connection tracking and rules management.
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  • 8

    Immutable Collections for Java

    Immutable/Persistent Collections Library

    Library providing immutable/persistent collection classes for Java. While collections are immutable they provide methods for adding and removing values by creating new modified copies of themselves. Each copy shares as much as possible of its structure with other copies to minimize memory consumption. The library includes a singly linked (cons/cddr style) list/stack, an integer trie based indexed list, a 2-3 tree based random access indexed list, a 2-3 tree based map, a hash trie based map, and hash and tree based sets, and sparse arrays. All collections provide immutable Cursor as well as standard Iterator classes for looping through all elements. A utility class provides functional style algorithmic processing of Cursors including foldLeft, foldRight, collect, select, and reject. The 2-3 tree and integer trie classes are optimized for performance and can be used alongside java.util Collections when immutability is needed for safe data sharing.
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  • 9

    Impressora Plugin

    Implementação de uso simples para impressoras não fiscais

    Com essa biblioteca você pode implementar de forma simples o uso de mini impressoras não fiscais das marcas mais usadas no mercado
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  • 10
    Incanter

    Incanter

    Clojure-based, R-like statistical computing and graphics environment

    Incanter is a Clojure-based, R-like statistical computing and visualization library running on the JVM. It integrates core numerical libraries like Parallel Colt and JFreeChart to deliver data manipulation, modeling, statistical tests, and charting in a REPL-friendly environment. Start by visiting the Incanter website for an overview, check out the documentation page for a listing of HOW-TOs and examples, and then download either an Incanter executable or a pre-built version of the latest build of Incanter, which includes all the necessary dependencies, and unpack the file (if you would like to build it from source, read Building Incanter). You also might need to install libgfortran3 library, which is required for jblas, which is powering matrix operations (see jblas wiki for more details).
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  • 11
    InfiniteCycleViewPager

    InfiniteCycleViewPager

    Infinite cycle ViewPager with two-way orientation

    Infinite cycle ViewPager with two-way orientation and interactive effect.
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  • 12
    Libaries and plugins for java developpement with Idea IntelliJ
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  • 13
    Interfuse is a workflow framework that joins ("fuses") the services, rules and objects of a traditional application with user-defined workflow. Interfuse is lightweight and designed to be embedded in existing Java-based applications.
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  • 14
    Intrepid 2
    Java RMI replacement. *** Project moved to GitHub *** https://github.com/robeden/intrepid
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  • 15
    IrcAppender

    IrcAppender

    IrcAppender forwards important log4j messages to an IRC channel

    IrcAppender is an appender for the Apache log4j system which forwards important logging event to an IRC channel. Output is controlled by the log4j configuration.
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  • 16
    A framework based on a concept of isolation. The isolation level of each component allow interchanging any of them for other with a similar function
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  • 17
    A Java library whose aim is to help developers to create Iterators. Filtering iterator, Concat iterators, etc... all implementing the new CloseableIterator interface. A persistence package is provided to help the user to create ResultSet iterators.
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  • 18
    A pure java DNS client implementation. Consists of a library and utilities for looking up the Internet domain names. The utilities are also able to fetch an entire domain zone and save it in the standard DNS zone file format.
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  • 19
    This project provides a set of libraries written in Java to easily manipulate Multi-Criteria Decision Aid (MCDA) concepts, especially related to outranking methods, and XMCDA files.
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  • 20

    J-X-Way UNI-TE

    Java library for X-Way and/or UNI-TE communication.

    PROJECT HAS MOVED HERE: https://github.com/Elektordi/x-way-uni-te X-Way and UNI-TE (also used in Unitelway) are communication protocols for old Schneider Electrics PLCs (Programmable Logic Controllers), formerly "Modicon Télémécanique". The aim of this open-source project is to create a Java library to send and receive such data, because there is actually no open-source project at all in this field. Keep in mind that those protocols are old and not maintained anymore by any company, but still used in many old PLCs installations.
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  • 21

    J7Win

    A Java Wrapper for Windows API functions.

    This project is a set of Java wrapper classes for Win32 API functions. There is a parallel project called J7Linux which is the equivalent for Linux/Unix systems.
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  • 22
    JACo Gallery ( java gallery )
    JACo Gallery is a cross platform java image/photo gallery. Features: automatic thumbnails, resizing, automatic initialization from XML files and very easy to use in your java applications as a normal component or in web pages as java applet.
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  • 23
    JACo Image ( java image )
    A collection of utilities to ease the work with images in java programming language.
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  • 24
    Java Swing Loader component used to display the progress of some task.
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  • 25
    JACo Picasa is a handy, tiny component designed to help you working with Picasa Web Gallery.
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