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

    repr

    python's repr() in Java

    This is an attempt to create something akin to python's repr() in Java - a simple utility that you can throw arbitrary objects at and get a string that tells you everything about the object you want to know.
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  • 2
    A Java API for resources loading and resources injection.
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  • 3
    restSQL is an ultra-lightweight data access layer. It provides a simple REST-based HTTP or Java API to access updatable views. It executes in any standard JEE container and interoperates with multiple databases, currently MySQL and PostgreSQL.
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  • 4
    rmisockfactory

    rmisockfactory

    Collection of RMI Socket Factories

    This project contains a collection of RMI socket factories -- for instance gzip-encoded data sent over the wire, NIO-based communication etc.
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  • 5

    rubycollect4j

    Ruby Collections for Java

    The rubycollect4j implements all methods refer to Ruby Array, Hash and Enumerable. For further info, please visit http://ruby-doc.org website. For more documentation, please read JavaDoc. With Java 8: // Sort the characters by its frequency based on the word 'Mississippi' case-insensitively RubyArray<String> word = ra("Mississippi".split("(?!^)")); String result = word.map((c) -> { return c.toLowerCase(); }).sortBy((c) -> { return word.count(c); }).uniq().join(); p(result); // "mpis" With Java 6: // Sort the characters by its frequency based on the word 'Mississippi' case-insensitively final RubyArray<String> word = newRubyArray("Mississippi".split("(?!^)")); String result = word.map(new TransformBlock<String, String>() { public String yield(String c) { return c.toLowerCase(); } }).sortBy(new TransformBlock<String, Integer>() { public Integer yield(String c) { return word.count(c); } }).uniq().join(); p(result); // "mpis"
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  • 6
    The library for generating your DAO classes at runtime.
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  • 7
    sal
    Simple actor library for Java
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  • 8
    Schedule4j is a java library for scheduling jobs easily.
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  • 9
    A base set of libraries. Boilerplate type code and algorithms. Currently skuttil (Java util & parsing code) and searKit (generic Java search framework).
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  • 10
    Slimgrid is a Java library for grid computations which is lighter than other ones (JPPF, Hadoop, ...). The main design goals are: minimalism, simplicity, pervasiveness. If you need to grab something which does not require you to comprehend massive and complex API's, do exhaustive configurations and installations, is robust and reliable, uses just one port for all management and communication, then SlimGrid is the right choice. The SlimGrid is built on top of the Apache's ZooKeeper library for coordination of distributed systems and Apache Curator awesome API simplification. Slimgrid allows also one-way synchronization of grid application folders (from the server to workers). This is useful when the grid app has been updated. Slimgrid is very robust. One of his successful mission was to perform more than 140.000 tasks in the grid with 40+ computers located in three different countries (Norway, Germany, Canada) and behind various firewalls (University labs).
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  • 11

    smslib

    A universal API for sms messaging.

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  • 12
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  • 13
    Declarative event listener support for SpringFramework 2.5. Spring - listener allows you to configure event listeners conforming to JavaBeans specification.
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  • 14
    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.
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  • 15
    sshxcute
    sshxcute is a Java based tool used to execute command or script on remote machine via SSH protocol. sshxcute是Java编写的通过SSH协议远程执行命令或者脚本的工具。
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  • 16

    sudoku

    This a sudoku game using java like the on found in newspaper

    This a sudoku game using java like the on found in newspaper
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  • 17
    This project is a Java library with a set of general utilities designed to help swing developers. Some tools are: easy positioning of containers (windows), help issues on java.io, image backgroundabe components, etc.
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  • 18

    tarte

    Tarte project provides common API libraries among multi-languages.

    Tarte is a project which provides common API libraries among multiple programming languages.
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  • 19
    telescope-cf-library

    telescope-cf-library

    TeleScope-CF XML Content Filtering Library

    Current TeleScope-CF Java library implementation employs XML parsing and specific pattern-matching that provides standard logical operator constructs to construct the query over the values of XML elements and attributes applied to the XML message on the fly as it is provided in the form of a String object. The code base has been adopted from TeleScope CQ XML stream broker code base written in C. C code has been re-factored into Java with minor modifications. This general-purpose library could be used by any Java applications that are involved in the XML message content filtering. Example application scenarios could be intrusion detection, selective rule engines, targeted database insertions during the ETL process and various business logic scenarios. The library could also be used in XML routers and various web services for XML content filtering where XML is a common message passing format.
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  • 20
    Java library offering theory of sets/set theory functionality (complement, intersection, symetric difference, union, cartesian product and powerset). There's also an ant task/ant tasks included that provides the library's functionality
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  • 21
    threadandjuc

    threadandjuc

    High performance three-high-import import system

    threadandjuc is a Java learning repository focused on multithreading, concurrency, and JUC concepts. It is designed to help developers understand how Java concurrent programming works through examples, explanations, and practical project-style demonstrations. The project covers topics such as threads, locks, synchronization, thread pools, concurrent collections, and high-performance data handling. It is especially useful for Java developers preparing for interviews or improving their understanding of production-level concurrency patterns. Some material also explores large-scale import and high-throughput reporting scenarios, connecting theory to real performance problems. Its main value is giving learners a structured way to study Java concurrency beyond isolated code snippets.
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  • 22
    threeddonut

    threeddonut

    3D donut. Example of frojasg1.com libraries usage

    The application shows a 3D donut, that can be rotated with two sliders in both axis. It is a simple example of what can be done with frojasg1.com platform libraries: - Zoom option for components - Multi language - Dark mode option - Automatic Undo-Redo for text components, with popup menu included - Text Search/Replace window prepared to be used. - Base components for auto-completion windows. - Automatic component relocation after redimensioning a window. - Base classes for formating text on the fly in JTextPanes - Improved JFileChooser and other functions: - Basic functions of all kind. - Accurate image resizing. - Function to process images. - Classes to easy the xml file management (without validation) - JDK-17 compatibility You will find more about it at this web site: https://www.frojasg1.com:8443/downloads_web/web/html/donut.html?origin=sourceforge
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  • 23

    tiff4j

    Utility library for manipulating TIFF files in Java

    tiff4j is a Java library providing basic operations with TIFF files: * page count Preparing: * splitting * merging
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  • 24
    Tinybinding is a small framework that allows automated synchronization of values between objects including values of Swing Components.
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  • 25

    trifling

    API that contains collection of some miscellaneous useful classes

    API that contains collection of some miscellaneous useful classes
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