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
    Aliucord

    Aliucord

    A modification for the Discord Android App

    Aliucord is a modification for the Android Discord app.
    Downloads: 9 This Week
    Last Update:
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  • 2
    PSI Probe

    PSI Probe

    Advanced manager and monitor for Apache Tomcat

    Advanced manager and monitor for Apache Tomcat, forked from Lambda Probe. Generally supported versions for third-party tomcat providers align with their support but earlier versions may still work. It is advisable in every case to use only supported tomcat releases per specific vendor. Our support will only be against non-CVE releases.
    Downloads: 9 This Week
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  • 3
    QR Code generator library

    QR Code generator library

    High-quality QR Code generator library in Java, TypeScript/JavaScript

    This project aims to be the best, clearest library for generating QR Codes. My primary goals are flexible options and absolute correctness. The secondary goals are compact implementation size and good documentation comments. This work is an independent implementation based on reading the official ISO specification documents. I believe that my library has a more intuitive API and shorter code length than competing libraries out there. The library is designed first in Java and then ported to TypeScript, Python, Rust, C++, and C. It is open source under the MIT License. For each language, the codebase is roughly 1000 lines of code and has no dependencies other than the respective language’s standard library.
    Downloads: 9 This Week
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  • 4
    WebDriverManager

    WebDriverManager

    Automated driver management and helper features for Selenium WebDriver

    WebDriverManager is an open-source Java library that carries out the management (i.e., download, setup, and maintenance) of the drivers required by Selenium WebDriver (e.g., chromedriver, geckodriver, msedgedriver, etc.) in a fully automated manner. In addition, WebDriverManager provides other relevant features, such as the capability to discover browsers installed in the local system, building WebDriver objects (such as ChromeDriver, FirefoxDriver, EdgeDriver, etc.), and running browsers in Docker containers seamlessly. The primary use of WebDriverManager is the automation of driver management. For using this feature, you need to select a given manager in the WebDriverManager API (e.g., chromedriver() for Chrome) and invoke the method setup(). The following example shows the skeleton of a test case using JUnit 5, Selenium WebDriver, and WebDriverManager.
    Downloads: 9 This Week
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  • 5
    jclasslib bytecode editor

    jclasslib bytecode editor

    Visualizes all aspects of compiled Java class files

    jclasslib bytecode editor is a tool that visualizes all aspects of compiled Java class files and the contained bytecode. Many aspects of class files can be edited in the UI. In addition, it contains a library that enables developers to read and write Java class files and bytecode. All constant pool entries can be edited. Referenced constant pool entries can directly be edited from the context menu that is shown by the "Edit" button of attributes and constant pool entries. Bytecode instructions can be edited from the context menu.
    Downloads: 9 This Week
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  • 6
    red5-server

    red5-server

    Red5 Server core

    Red5 is an Open Source Flash Server written in Java that supports streaming Video (FLV, F4V, MP4, 3GP). Streaming Audio (MP3, F4A, M4A, AAC) Recording Client Streams (FLV and AVC+AAC in FLV container) Shared objects, live stream publishing, remoting, and protocols: RTMP, RTMPT, RTMPS, and RTMPE.
    Downloads: 9 This Week
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  • 7
    A Java JNA wrapper for Tesseract OCR API
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    Downloads: 45 This Week
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  • 8
    OpenAPI Generator

    OpenAPI Generator

    OpenAPI Generator allows generation of API client libraries

    With 50+ client generators, you can easily generate code to interact with any server which exposes an OpenAPI document. Maintainers of APIs may also automatically generate and distribute clients as part of official SDKs. Each client supports different options and features, but all templates can be replaced with your own Mustache-based templates. Getting started with server development can be tough, especially if you're evaluating technologies. We can reduce the burden when you bring your own OpenAPI document. Some generators support Inversion of Control, allowing you to iterate on design via your OpenAPI document without worrying about blowing away your entire domain layer when you regenerate code. Ever wanted to iteratively design a MySQL database, but writing table declarations was too tedious? OpenAPI documents allow you to convert the metadata about your API into some other format.
    Downloads: 7 This Week
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  • 9
    RoaringBitmap

    RoaringBitmap

    A better compressed bitset in Java

    Bitsets, also called bitmaps, are commonly used as fast data structures. Unfortunately, they can use too much memory. To compensate, we often use compressed bitmaps. Roaring bitmaps are compressed bitmaps which tend to outperform conventional compressed bitmaps such as WAH, EWAH or Concise. In some instances, roaring bitmaps can be hundreds of times faster and they often offer significantly better compression. They can even be faster than uncompressed bitmaps.
    Downloads: 7 This Week
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  • 10
    Svix

    Svix

    The enterprise-ready webhooks service

    Build a secure, reliable, and scalable webhook platform in minutes using the Svix webhook service. Webhooks require a lot more engineering time, resources and ongoing maintenance than you would first expect. Building a secure, reliable, and scalable webhook service is hard and time-consuming. We built it so you can focus on what matters most, your business. Customer endpoints fail or hang more often than you think. You need automatic retries to ensure deliverability. You need to monitor the deliverability of your webhooks to different endpoints, disable failing ones and notify your customers. Webhooks come with a myriad of security implications, such as SSRF, replay attacks and unauthenticated webhook events. You would need to build a UI for your users to add and remove endpoints, inspect logs and get ongoing reports. Offer your users a great developer experience, including the ability to test, inspect and replay their webhooks.
    Downloads: 7 This Week
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  • 11
    ta4j

    ta4j

    A Java library for technical analysis

    Ta4j is an open-source Java library for technical analysis. It provides the basic components for the creation, evaluation, and execution of trading strategies. Ta4j is available on Maven Central. You can also download example code from the maven central repository. The wiki is the best place to start learning about ta4j. For more detailed questions, please use the issues tracker. We can calculate indicators over this bar series, in order to forecast the direction of prices through the study of past market data. Then we have to build our trading strategy. It is made of two trading rules, one for entry, the other for exit. Ta4j comes with a set of basic trading rules/strategies which can be combined using boolean operators. Trading strategies can be easily compared according to a set of analysis criteria. Ta4j can also be used for live trading with more complicated strategies.
    Downloads: 7 This Week
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  • 12
    Importer library to import assets from different common 3D file formats such as Collada, Blend, Obj, X, 3DS, LWO, MD5, MD2, MD3, MDL, MS3D and a lot of other formats. The data is stored in an own in-memory data-format, which can be easily processed. www.open3mod.com/ is a 3D model viewer and exporter based on Assimp that is also Open Source.
    Downloads: 30 This Week
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  • 13
    A library for identifying URLs in content and checking their validity on the internet
    Downloads: 90 This Week
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  • 14
    AnLinux

    AnLinux

    AnLinux allow you to run Linux on Android without root access

    AnLinux allow you to run Linux on Android without root access. The bash script downloads the image over the internet, then decompresses the image, and then mounts it using PRoot.
    Downloads: 6 This Week
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  • 15
    ImGui Java

    ImGui Java

    JNI based binding for Dear ImGui

    imgui-java is a comprehensive Java binding for Dear ImGui, the popular immediate-mode GUI library used for real-time tools and debug interfaces. This binding allows Java applications—including those using LWJGL or JOGL—to leverage ImGui’s fast and flexible GUI features without switching languages. With support for native backends and OpenGL rendering, imgui-java is perfect for game engines, development tools, and editors that need an intuitive GUI system. It includes integrations for multiple platforms and rendering contexts, with regular updates to match upstream ImGui releases.
    Downloads: 6 This Week
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  • 16
    Infinity For Reddit

    Infinity For Reddit

    A Reddit client for Android

    A Reddit client on Android written in Java. It does not have any ads and it features a clean UI and smooth browsing experience. Infinity is a beautiful, feature-rich app that offers a smooth Reddit browsing experience. It is completely free and ad-less; you can browse Reddit without interruptions or distractions. Built by a passionate university student, Infinity is open source.
    Downloads: 6 This Week
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  • 17
    mvnd

    mvnd

    Apache Maven Daemon

    Apache Maven is a software project management and comprehension tool. Based on the concept of a project object model (POM), Maven can manage a project's build, reporting and documentation from a central piece of information.
    Downloads: 6 This Week
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  • 18

    ConcatPDF

    PDF Concatenation Tool

    ConcatPDF is the tool to concatenate PDF files. It can concatenate, extract, encrypt, decrypt, configure PDF files, convert image files to PDF. GUI version and CUI version are both available. iText.NET is iText porting on .NET Framework by J#. This library allows you to generate PDF, (X)HTML, XML, RTF files on Microsoft.NET Framework including ASP.NET.
    Downloads: 39 This Week
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  • 19
    Glide

    Glide

    Android image loading & caching library focused on smooth scrolling

    Glide is a fast and efficient open source image loading and caching library for Android that focuses on smooth scrolling. It supports fetching, decoding and displaying images, video stills as well as animated GIFs, with a simple and easy to use interface and API. Glide offers a performant and extensible resource decoding pipeline and automatic resource pooling, and a flexible API that allows developers to plug in to just about any network stack. It is primarily focused on making any type of a list of images as smooth and fast as possible, and is able to achieve this through smart and automatic downsampling and caching, aggressive re-use of resources and deep lifecycle integration. Apart from smooth and speedy scrolling, it’s also good for any case where fetching, resizing, and displaying of a remote image is needed.
    Downloads: 5 This Week
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  • 20
    GraphHopper Routing Engine

    GraphHopper Routing Engine

    Open source routing engine for OpenStreetMap

    GraphHopper invests in an active open source community. Our flagships are the GraphHopper routing engine and jsprit, the toolkit for solving rich vehicle routing problems. We promote a fair & diverse mindset. jsprit is a Java based toolkit for solving rich traveling salesman problems (TSP) and vehicle routing problems (VRP). It is lightweight, flexible, easy-to-use, and based on a single all-purpose meta-heuristic. The GraphHopper routing engine is fast and memory-efficient, using Java. It runs server side, offline on Android and iOS. It uses OpenStreetMap data, but can import other data sources as well. GraphHopper is a fast and memory-efficient routing engine released under Apache License 2.0. It can be used as a Java library or standalone web server to calculate the distance, time, turn-by-turn instructions and many road attributes for a route between two or more points. Beyond this "A-to-B" routing it supports "snap to road", Isochrone calculation, mobile navigation and more.
    Downloads: 5 This Week
    Last Update:
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  • 21
    Spring Integration

    Spring Integration

    Provides an extension of the Spring programming model

    Extends the Spring programming model to support the well-known Enterprise Integration Patterns. Spring Integration enables lightweight messaging within Spring-based applications and supports integration with external systems via declarative adapters. Those adapters provide a higher-level of abstraction over Spring’s support for remoting, messaging, and scheduling. Spring Integration’s primary goal is to provide a simple model for building enterprise integration solutions while maintaining the separation of concerns that is essential for producing maintainable, testable code.
    Downloads: 5 This Week
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  • 22
    jsoup

    jsoup

    Java library for working with real-world HTML

    jsoup is a Java library for working with real-world HTML. It provides a very convenient API for fetching URLs and extracting and manipulating data, using the best of HTML5 DOM methods and CSS selectors. jsoup implements the WHATWG HTML5 specification, and parses HTML to the same DOM as modern browsers do. jsoup is designed to deal with all varieties of HTML found in the wild; from pristine and validating, to invalid tag-soup; jsoup will create a sensible parse tree. The parser will make every attempt to create a clean parse from the HTML you provide, regardless of whether the HTML is well-formed or not. You have HTML in a Java String, and you want to parse that HTML to get at its contents, or to make sure it's well formed, or to modify it. The String may have come from user input, a file, or from the web.
    Downloads: 5 This Week
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  • 23
    syncthing-android

    syncthing-android

    Wrapper of syncthing for Android

    Syncthing is a continuous file synchronization program. It synchronizes files between two or more computers in real time, safely protected from prying eyes. Your data is your data alone and you deserve to choose where it is stored, whether it is shared with some third party, and how it’s transmitted over the internet. None of your data is ever stored anywhere else other than on your computers. There is no central server that might be compromised, legally or illegally. All communication is secured using TLS. The encryption used includes perfect forward secrecy to prevent any eavesdropper from ever gaining access to your data. Every device is identified by a strong cryptographic certificate. Only devices you have explicitly allowed can connect to your other devices.
    Downloads: 5 This Week
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  • 24
    Moved to https://github.com/DANS-KNAW/dans-dbf-lib.
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    Downloads: 42 This Week
    Last Update:
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  • 25
    Java Neural Network Framework Neuroph
    Neuroph is lightweight Java Neural Network Framework which can be used to develop common neural network architectures. Small number of basic classes which correspond to basic NN concepts, and GUI editor makes it easy to learn and use.
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    Downloads: 19 This Week
    Last Update:
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