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
    RoundCornerProgressBar

    RoundCornerProgressBar

    [Android] Round Corner Progress Bar Library for Android

    Round corner is cool. Let's make your progress bar with round corner. Colorful rounded corner progress bar.
    Downloads: 2 This Week
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  • 2
    TengineKit

    TengineKit

    TengineKit - Free, Fast, Easy, Real-Time Face Detection

    Free, Fast, Easy, Real-Time Face Detection & Face Landmarks & Face Attributes & Hand Detection & Hand Landmarks & Body Detection & Body Landmarks & Iris Landmarks & Yolov5 SDK On Mobile. TengineKit is an easy-to-integrate AI algorithm SDK. At present, it can run on various mobile phones at very low latency. We will continue to update this project for better results and better performance!
    Downloads: 2 This Week
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  • 3
    Testcontainers Java

    Testcontainers Java

    Testcontainers is a Java library that supports JUnit tests

    Testcontainers for Java is a Java library that supports JUnit tests, providing lightweight, throwaway instances of common databases, Selenium web browsers, or anything else that can run in a Docker container. Use a containerized instance of a MySQL, PostgreSQL or Oracle database to test your data access layer code for complete compatibility, but without requiring complex setup on developers' machines and safe in the knowledge that your tests will always start with a known DB state. Any other database type that can be containerized can also be used. For running your application in a short-lived test mode with dependencies, such as databases, message queues or web servers. Use containerized web browsers, compatible with Selenium, for conducting automated UI tests. Each test can get a fresh instance of the browser, with no browser state, plugin variations or automated browser upgrades to worry about. And you get a video recording of each test session.
    Downloads: 2 This Week
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  • 4
    TwelveMonkeys

    TwelveMonkeys

    Additional plug-ins and extensions for Java's ImageIO

    TwelveMonkeys ImageIO provides extended image file format support for the Java platform, through plugins for the javax.imageio. package. The main goal of this project is to provide support for formats not covered by the JRE itself. Support for these formats is important, to be able to read data found "in the wild", as well as to maintain access to data in legacy formats. As there is lots of legacy data out there, we see the need for open implementations of readers for popular formats.
    Downloads: 2 This Week
    Last Update:
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  • 5
    jCasbin

    jCasbin

    An authorization library that supports access control models

    An authorization library that supports access control models like ACL, RBAC, ABAC for Golang, Java, C/C++, Node.js, Javascript, PHP, Laravel, Python, .NET (C#), Delphi, Rust, Ruby, Swift (Objective-C), Lua (OpenResty), Dart (Flutter) and Elixir. In Casbin, an access control model is abstracted into a CONF file based on the PERM metamodel (Policy, Effect, Request, Matchers). So switching or upgrading the authorization mechanism for a project is just as simple as modifying a configuration. Besides memory and file, Casbin policy can be stored into lots of places. Currently, dozens of databases are supported, from MySQL, Postgres, Oracle to MongoDB, Redis, Cassandra, AWS S3. jCasbin is a powerful and efficient open-source access control library for Java projects. It provides support for enforcing authorization based on various access control models.
    Downloads: 2 This Week
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  • 6
    mall-swarm

    mall-swarm

    Microservices edition of the mall e-commerce system

    mall-swarm is the microservices edition of the mall e-commerce system, designed to illustrate how an enterprise-scale e-commerce backend can be built using Spring Cloud Alibaba, Spring Boot 3.x, Sa-Token (authentication), MyBatis, Elasticsearch, Docker and Kubernetes. It includes modules for gateway, auth, search, portal, admin, monitoring, config, registry, and more, and integrates a Vue-based management frontend. The repository is structured to show how cross-service concerns like service registry, configuration center, monitoring, distributed transactions, API gateway and messaging are done in microservice architecture. It is used as a teaching platform to help engineers migrate from monolith to microservices, grasp the patterns, pitfalls and infrastructure considerations (e.g., Nacos, Seata). The documentation includes diagrams of system architecture, business architecture, service organization, and shows how to set up on Kubernetes.
    Downloads: 2 This Week
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  • 7
    springdoc-openapi

    springdoc-openapi

    Library for OpenAPI 3 with spring-boot

    An extended support for springdoc-openapi v1 project is now available for organizations that need support beyond 2023. The springdoc-openapi Java library helps automating the generation of API documentation using Spring Boot projects. springdoc-openapi works by examining an application at runtime to infer API semantics based on Spring configurations, class structure and various annotations. The library automatically generates documentation in JSON/YAML and HTML formatted pages. The generated documentation can be complemented using swagger-api annotations.
    Downloads: 2 This Week
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  • 8
    CSSBox

    CSSBox

    Pure Java HTML / CSS rendering engine

    CSSBox is an (X)HTML/CSS rendering engine written in pure Java. Its primary purpose is to provide a complete information about the rendered page suitable for further processing. However, it also allows displaying the rendered document.
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    Downloads: 11 This Week
    Last Update:
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  • 9
    Javaluator

    Javaluator

    A java infix evaluator based on "Shunting Yard" algorithm.

    Evaluate an arithmetic expression is as simple as: Double result = new DoubleEvaluator().evaluate("(e^3-1)*sin(pi/4)*ln(pi^2)"). But Javaluator provides you with much more ... Key features: - Functions support, including variable argument count. - Constants support: e, pi, etc ... - Variables support: Example sin(x) for x = pi/4. - Highly configurable: Reduce the built-in operator or function sets, define your own brackets. - Extensible: Define your own grammar, or extends the existing one. - Localizable: Define localized names for functions or constants. - Syntax check - Small footprint: 26kB, no additionnal library required. - Fully documented Please visit the project site to learn more : http://javaluator.fathzer.com If you use Javaluator in your product, we will be happy to add a link to your product in the Javaluator web site. Send an email to javaluator@fathzer.com. If you think Javaluator is valuable, vote up below.
    Downloads: 11 This Week
    Last Update:
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  • 10
    The ftp4j library implements a Java full-featured FTP client. With ftp4j embedded in your application you can: transfer files (upload and download), browse the FTP site (directory listing), create, delete, rename and move directories and files.
    Downloads: 11 This Week
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  • 11
    7-Zip-JBinding

    7-Zip-JBinding

    Java wrapper for 7z archiver engine

    Native (JNI) cross-platform library to extract (password protected, multi-part) 7z Zip Rar Tar Split Lzma Iso HFS GZip Cpio BZip2 Z Arj Chm Lhz Cab Nsis Deb Rpm Wim Udf archives and create 7z, Zip, Tar, GZip & BZip2 from Java.
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    Downloads: 10 This Week
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  • 12
    A library help for signing data with PKCS11 token (certificates with SHA1withRSA Sign Algorithm) and create CMS packages. It uses Bouncy Castle Crypto API and SUNPKCS11. Also it verify the signed data and verify signing certificate's OCSP control.
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    Downloads: 35 This Week
    Last Update:
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  • 13

    FSP - File Service Protocol Suite

    UDP File transfer protocol

    FSP - File Service Protocol. FSP is lightweight UDP based protocol for transferring files. It is designed for anonymous transfers over unreliable networks.
    Downloads: 12 This Week
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  • 14
    jni4net

    jni4net

    Fast, object oriented, intraprocess bridge between JVM and CLR

    Fast, object oriented, intraprocess bridge between JVM and CLR
    Downloads: 32 This Week
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  • 15
    Android Debug Database

    Android Debug Database

    A library for debugging android databases and shared preferences

    Android Debug Database allows you to view databases and shared preferences directly in your browser in a very simple way. Android Debug Database is a powerful library for debugging databases and shared preferences in Android applications. Delete database rows and shared preferences. Search in your data. Sort data. Download database. Debug Room inMemory database. As this library is auto-initialize, if you want to get the address log, add the following method and call (we have to do like this to avoid build error in release build as this library will not be included in the release build) using reflection. Using the Android Debug Database with an encrypted database. See all the data in the shared preferences used in your application. Run any sql query on the given database to update and delete your data.
    Downloads: 1 This Week
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  • 16
    Android-Bootstrap

    Android-Bootstrap

    Bootstrap style widgets for Android, with Glyph Icons

    Android Bootstrap is an Android library which provides custom views styled according to the Twitter Bootstrap Specification. This allows you to spend more time on development rather than trying to get a consistent theme across your app, especially if you are already familiar with the Bootstrap Framework. Create buttons that support Glyph icons, and are themeable using Bootstrap Brands. BootstrapButtonGroup Allows BootstrapButtons to be grouped together and their attributes controlled en masse. BootstrapProgressBar Displays progress in a bar from 0-100, and animates updates to the current progress. BootstrapLabel Displays non-clickable text in a widget similar to the BootstrapButton, sizable using H1-H6 elements. BootstrapCircleThumbnail Displays images in a center-cropped Circular View, themed with BootstrapBrand.
    Downloads: 1 This Week
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  • 17
    Android-GoogleDirectionLibrary

    Android-GoogleDirectionLibrary

    Library for Google Direction API for Google Maps Android API v2

    Library for Google Direction API for Google Maps Android API v2.
    Downloads: 1 This Week
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  • 18
    EasyDeviceInfo

    EasyDeviceInfo

    [Android Library] Get device information in a super easy way

    Android library to get device information in a super easy way. The library is built for simplicity and approachability. It not only eliminates most boilerplate code for dealing with device information but also provides an easy and simple API to retrieve them. EasyDeviceInfo is split into multiple module-libraries, v2.2.0 onwards. Use the appropriate one as per your requirement.
    Downloads: 1 This Week
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  • 19

    EventBus

    The no.1 event library for Android

    EventBus is an open-source library for Android and Java that uses the publisher/subscriber pattern for loose coupling, enabling central communication to decoupled classes with just a few lines of code. It simplifies communication between Activities, Threads, Services and other components while also simplifying code, eliminating dependencies, and overall improving app development speed and quality. EventBus offers several advanced features, such as jump start, delivery threads, subscriber priorities, and many others. It is specifically optimized for high performance and is small at just ~60k jar. It's been proven by numerous apps with more than a billion total installs.
    Downloads: 1 This Week
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  • 20
    Heritrix

    Heritrix

    Internet Archive's open-source, web-scale, web crawler project

    Heritrix is the Internet Archive's open-source, extensible, web-scale, archival-quality web crawler project. Heritrix (sometimes spelled heretrix, or misspelled or missaid as heratrix/heritix/heretix/heratix) is an archaic word for heiress (woman who inherits). Since our crawler seeks to collect and preserve the digital artifacts of our culture for the benefit of future researchers and generations, this name seemed apt. Heritrix is designed to respect the robots.txt exclusion directives† and META nofollow tags. Please consider the load your crawl will place on seed sites and set politeness policies accordingly. Also, always identify your crawl with contact information in the User-Agent so sites that may be adversely affected by your crawl can contact you or adapt their server behavior accordingly.
    Downloads: 1 This Week
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  • 21
    Hutool

    Hutool

    A set of tools that keep Java sweet

    Hutool is a small but comprehensive Java tool class library. Through static method encapsulation, it reduces the learning cost of related APIs, improves work efficiency, makes Java as elegant as a functional language, and makes the Java language "sweet". The tools and methods in Hutool come from each user's meticulous attention to detail. It covers all aspects of the underlying code of Java development. It is not only a sharp tool to solve small problems in large-scale project development, but also an efficiency responsibility in small-scale projects. Hutool is a friendly replacement for the "util" package in the project. It saves developers the time of encapsulating public classes and public tool methods in the project, allowing developers to focus on business while avoiding bugs caused by imperfect encapsulation to the greatest extent.
    Downloads: 1 This Week
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  • 22
    Instacapture 2.0

    Instacapture 2.0

    Android library to capture screenshot from your app

    Android library to capture screenshots from your app.
    Downloads: 1 This Week
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  • 23
    JSqlParser

    JSqlParser

    JSqlParser parses an SQL statement and translate it into a hierarchy

    JSqlParser is a SQL statement parser. It translates SQLs in a traversable hierarchy of Java classes. JSqlParser is not limited to one database but provides support for a lot of specials of Oracle, SqlServer, MySQL, PostgreSQL. To name some, it has support for Oracles join syntax using (+), PostgreSQLs cast syntax using ::, relational operators like != and so on. Then the result can be accessed in a structured way. The generated Java class hierarchy can be navigated using the Visitor Pattern.
    Downloads: 1 This Week
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  • 24
    JTS Topology Suite

    JTS Topology Suite

    Java library for creating and manipulating vector geometry.

    The JTS Topology Suite is a Java library for creating and manipulating vector geometry. It also provides a comprehensive set of geometry test cases, and the TestBuilder GUI application for working with and visualizing geometry and JTS functions.
    Downloads: 1 This Week
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  • 25
    JaCoCo Java Code Coverage Library

    JaCoCo Java Code Coverage Library

    Java Code Coverage Library

    JaCoCo is a free code coverage library for Java, which has been created by the EclEmma team based on the lessons learned from using and integrating existing libraries for many years.
    Downloads: 1 This Week
    Last Update:
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