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
    PlaceHolderView

    PlaceHolderView

    This library provides advance views for lists and stacks

    PlaceHolderView is an Android library for building advanced lists, expandable collections, infinite feeds, and swipeable card stacks. Some components extend RecyclerView, while others use independent implementations tailored to gesture-driven interfaces. Its annotation-based API reduces adapter and binding boilerplate by generating binding classes during compilation. PlaceHolderView offers a standard list container, an infinite-scrolling variant, and a parent-child expandable view. SwipePlaceHolderView supports Tinder-style card stacks, while SwipeDirectionalView reports swipe directions and touch events. The library includes Java and Kotlin integration paths, although its dependencies and support-library examples reflect an older Android ecosystem.
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  • 2
    A Java library for creation and editing of several playlist formats.
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  • 3
    PluginsIB

    PluginsIB

    Repositori de Plugins per les Aplicacions del KitAnibal

    1) == MOGUT A GITHUB: https://github.com/GovernIB/pluginsib == Repositori de Plugins per les Aplicacions del KitAnibal i qualsevol aplicació que vulgui reutilitzar funcionalitats configurables emprant un plugin. Els plugins que actualment estan implementats són: (1) Generació de Codi de barres (BarCodes): barcode128, pdf417 i qrcode (2) Validació de Certificats Digitals: basic i @firma (3) Conversió de Format de Documents: OpenOffice en mode servei (4) Custòdia de Documents: sistema de fitxers i Custòdia CAIB. (5) Exportació de Dades: exporta una matriu de dades a formats com csv, excel o ods. (6) Escaneig de Documents via Web: Dynamic Web Twain (7) Informació d'usuaris: informació de les dades d'un usuari a partir del seu username o identificador administratiu (NIF) i/o informació de Roles: BBDD o LDAP.
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  • 4

    Poor Man's Timing And Profiling

    Library tools to collect timing in Java, C, C++

    A collection of library code and tools for application execution profiling and performance testing. You can create stopwatches to time select portions of your code. You can measure differences (often to sub-millisecond accuracy) between clocks on different machines. You can log application events in a .csv format for subsequent analysis. You can also generate CPU loading logs in a .csv format.
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  • 5
    Connector to Primavera P6 Project Manager database. Analog Primavera API.
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  • 6
    Programming Accessory Kit

    Programming Accessory Kit

    PAK is a collection of library code to handle the overhead of coding

    PAK is a collection of library code to handle the overhead of coding things like read-write locks, reflective multithreaded programming and simple file io. This is a java library collection, please see my API below...
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  • 7
    ProgressManager

    ProgressManager

    Listen the progress of downloading and uploading in Okhttp

    ProgressManager is an Android networking utility designed to monitor and manage upload and download progress for HTTP requests built with OkHttp. The library simplifies the implementation of progress tracking in Android applications by wrapping request and response bodies with listeners that report transfer status in real time. It is especially useful for applications that handle file uploads, media downloads, or large network transfers where users expect visible progress feedback. The project supports integration with Glide and other Android networking workflows, enabling developers to track image loading and resource downloads without extensive boilerplate code. Its architecture emphasizes minimal intrusion into existing networking stacks while maintaining compatibility with common Android development patterns. ProgressManager is widely used in applications requiring responsive file transfer interfaces and efficient network progress monitoring.
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  • 8
    Qigsaw

    Qigsaw

    Dynamic modularization library which is based on Android App Bundles

    Qigsaw is a dynamic modularization library which is based on Android App Bundles. It supports dynamic delivery for split APK without reinstalling the base one. Qigsaw-gradle-plugin will upload split APKs which require dynamic delivery during compilation, so you have to implement SplitApkUploader to upload split APKs to your own CND server.
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  • 9
    PROJECT MOVED: https://github.com/workplacesystems/queuj Java job queue built for concurrency control, scalability, persistence and resilience,
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  • 10

    QuickSlide

    A tool to generate HTML-based slide shows.

    This tool allow the generation of slide shows in HTML format (to run simply in the browser). It can not replace Microsoft Power Point, but, it allows you to create a slide show by writing Java code. The generated slide show can be run easily in the browser so it is platform independent and does not need any additional software installation, even on new installed OS or Smart phones. In this first pre-alpha version, the generated code supports simple text and basic lists only, but, I hope to add more features in the future.
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  • 11

    QwicGUI

    Java GUIs made easy!

    QwicGUI, an easy-to-use open source Java class library developed by Impact Computing (http://www.impact-computing.com/), simplifies Java GUI development and offers out-of-the-box functionality not provided by the standard Java GUI classes.
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  • 12
    this project was moved to http://sourceforge.jp/projects/r42utils/wiki/FrontPage
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  • 13
    RCER is a SAP R/3 Connector for Eclipse Rich Client Platform applications. It wraps up the SAP Java Connector (JCo) in a reusable way and provides additional common functions like connection definition, login dialog and status monitoring.
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  • 14

    RDF P

    RDF Eclipse Plugins

    RDF P (P stands for project or plugin or PIXEL) provides Eclipse plugins for working with RDF data: editors, views, builders, wizards etc. RDF P is based on OpenRDF/Sesame and bundles OWLIM Lite. Currently follwing features are included: * Turtle editor with syntax highlighting * Outline page displaying the RDF contents as table * Graph view displaying RDF as interactive graph * Builder to assemble RDF files into a local repository * SPARQL editor which access the local repository * New Turtle file wizard You can download Tawny which is an Eclipse IDE edition demonstrating RDF P.
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  • 15
    REST Countries

    REST Countries

    Get information about countries via a RESTful API

    Get information about countries via a RESTful API.
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  • 16
    Reporting engine library written in C. Create one XML file and generate PDF, HTML, TXT, and CSV reports based on queries. Has support for MySQL, PostgreSQL, ODBC. Bindings for PHP, Java, Python.
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  • 17
    Easy-to-use Reverse Polish Notation (RPN) Java Library.
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  • 18
    A fast XML pull-parser with constant buffer size. Only a subset of XML 1.0 is supported.
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  • 19
    RRDiagram

    RRDiagram

    Generate railroad diagrams from code or BNF. Generate BNF from code

    RR Diagram allows to generate railroad diagrams (also called syntax diagrams) from code or from BNF notation. The output format is SVG which can be integrated to web pages and where rules can contain links. RR Diagram can also be used to generate BNF notation from a model.
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  • 20
    Raken, web service controller, is based on JSON as a data definition language. it utilizes simple protocol, optional asynchronous interaction, recovery, localization, security, caching, batch, and multi-part messaging.
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  • 21
    RcpFuse application framework or skeleton that integrates Java libraries to help you develop Rich applications quickly and efficiently. With similar design goals as AppFuse; and in fact the first version was an offshoot from AppFuse.
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  • 22
    This project is the implementation of a communication protocol for real time exchange between remote components.
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  • 23
    RecyclerViewHeader

    RecyclerViewHeader

    Super fast and easy way to create header for Android RecyclerView

    Super fast and easy way to create header for Android RecyclerView. Just use a RecyclerView.Adapter that can inflate multiple types of items.
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  • 24

    RedComm

    RedComm is a Java library simplifying communication with a serial port

    RedComm is a lightweight Java library. It simplifies communication over the serial port by providing methods and interfaces, which can be used to read and write to the serial port or over an emulated serial cable by using bluetooth. The major focus is on the ease of use of the library. Besides that the experienced user has the ability to change the reading and writing behaviour of the library. This means the user can easily extend and customize the RedComm library. Internally RedComm uses part of the RxTx Library (http://rxtx.qbang.org/wiki/index.php/Main_Page) for port communication. Thus RedComm helps the unexperienced user using RxTx. RxTx is licensed under the LGPL 2.1 (http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html). RedComm also provides facilities for event based serial communication with the help of threading in order to non-block ie. the gui thread of the corresponding application. RedComm is ideally suited for education e.g at schools.
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  • 25
    RedRoo implements a framework for defining and executing hierarchical state machines. As a Red Kangaroo jumps from place to place, RedRoo will transition your application from state to state feeding on the events you pass to it. So get jumping!
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