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
    Java library that generates banners made of characters. It can use internal bitmap small fonts or JVM system TTF fonts.
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  • 2
    Similar to StringTokenizer already in the Java standard library, but capable of discerning different types of data as tokens (e.g. "a=1" will yield 3 tokens) as it doesn't rely on whitespaces or some single delimiter (as StringTokenizer does).
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  • 3
    A complete cross-platform Java USB Library
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  • 4
    This project has moved to http://github.com/alexcoppo/jautl
    Downloads: 0 This Week
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  • 5

    Java Utilities Library Samples

    Samples for the JAUTL library

    This project has moved to http://github.com/alexcoppo/jautl_samples
    Downloads: 0 This Week
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  • 6

    Java Validation Framework

    Java validation framework (not JSR-303 implementation).

    This framework allows to modify (correct) test values; supports validation of localized values; allows to convert values into and from text representation; formats error messages, depending on the context; supports metadata, which allows to check any entity types (not only Java Beans or POJOs) and more. Also this framework has long list of predefined validation components.
    Downloads: 0 This Week
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  • 7
    Java and Spring Tutorials

    Java and Spring Tutorials

    Getting Started with Spring Boot 3

    Java and Spring Tutorials is a large-scale educational codebase that provides practical examples and tutorials covering a wide range of software development topics, primarily focused on Java and related ecosystems. It serves as a companion resource for Baeldung articles, offering real-world code implementations that demonstrate concepts such as Spring Boot, persistence frameworks, REST APIs, security, testing, and more. The repository is organized into multiple modules, each targeting specific technologies or frameworks, making it easy for developers to explore topics independently. It emphasizes best practices, clean code structure, and production-ready patterns, allowing learners to not only understand theoretical concepts but also apply them in real applications. The project is continuously updated to reflect modern development trends and evolving technologies, ensuring relevance for both beginners and experienced developers.
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  • 8
    Java ORM liblary for fast and easy creations of ORM objects and tables.
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  • 9
    JDOM extention to manage huge (big) xml file. Make able to have a persisted Document Object Model (DOM).
    Downloads: 0 This Week
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  • 10
    Java utility classes

    Java utility classes

    Utility classes for Java

    This is a set of Java classes and static methods for: - System process management on a machine, e.g. starting a process, starting a process via PowerShell; getting process PID, waiting, destroying, getting all processes, etc. - Buffered file reader for both text (ASCII) and binary files, specifically useful for parallel file parsing and/or for large files. - Async. timer with a variable precision. - Very easy HTTP GET request sender and data retriever. _____________ - All compiled Java classes are in org.engitex.utils package. - Package com.company contains corresponding examples showing how to use the main classes and methods from org.engitex.utils. - Files readme.md, blas.F, Wrench_3dstudio.3ds, nut.stl are used in BufferedFileReaderExample.
    Downloads: 0 This Week
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  • 11
    A library for cross-platform vector graphics cut and paste in java. It allows one to draw graphics which can the be pasted into word or openoffice. It handles Graphics2D, but not bitmap picture inclusion nor transparencies.
    Downloads: 0 This Week
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  • 12
    Java2RDB

    Java2RDB

    Projekt serializacji Java2RDB

    Projekt Serializacji Java2RDB
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  • 13
    JavaEETest

    JavaEETest

    Spring, SpringMVC, MyBatis, Spring Boot cases

    JavaEETest is a comprehensive example repository showcasing Java web development using key technologies like Spring, Spring MVC, MyBatis, and Spring Boot. The project contains many small self-contained demo modules that demonstrate specific concepts such as dependency injection, MVC routing, ORM mapping, transaction management, caching, security configuration, and database interaction. It provides ready-to-run code that learners can inspect to understand how Java web apps are structured and how these frameworks collaborate under the hood. Tutorials and example code include working with REST APIs, session management, dynamic SQL with MyBatis, annotation-driven Spring configuration, and more advanced features like caching and Spring Security. Because it includes numerous cases, from beginner-level to more sophisticated scenarios, it’s widely used as a reference for both students and practicing developers refining their skills.
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  • 14

    JavaGimmicks

    Utility classes, APIs and tools for Java

    A set of helper and utility classes, APIs and tools for the Java Programming Language. For more details - pleas visit the project homepage.
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  • 15

    JavaJsonWrapping

    Simplified reading/writing/manipulation of Json with Java

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  • 16

    JavaLambdaCompose

    Utility methods for composing functional lambda expressions

    Provides for composing functional lambda instances to improve run-time efficiency and flexibility. The composition avoids excessive call stacking when processing multiple Predicate or Consumer instances, and can avoid the processing overhead of Collection.stream().filter().forEach() by replacing with Collection.forEach() using a composed Consumer from a Predicate and Consumer. Includes utility methods for composing an Iterable or array of Predicate instances into a single Predicate instance for testing for all, any, or none of the Predicate results. Includes utility methods for composing an Iterable or array of Consumer instances into a single Consumer instance. Includes utility methods for composing an Iterable or array of Predicate instances with an Iterable or array of Consumer instances into a single Consumer that tests for all, any, or none of the Predicate results. Includes a utility method for using streams to split a Collection according to comparators.
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  • 17

    JavaMutex

    Provides 100% pure Java mutual exclusion.

    Freely redistributable open source 100% pure Java for mutual exclusion. Read-write and read-only reentrant lock, condition variable, atomic wraps for Boolean, Integer, Long, and Reference. Cell pool with optional locking, object exchanger, Intersect.
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  • 18
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  • 19
    JavaRTMP is a Java library for interacting with Adobe Flash Player and Adobe Air applications via the RTMP protocol
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  • 20
    The Java Teamspeak 3 Server Query Software Development Kit is a Java Library that provides Classes to access the Teamspeak Server Query for easy integreating TSSQ into Java Desktop- or Web-Applications.
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  • 21
    JavaTutorial

    JavaTutorial

    Ten years of experience as a veteran driver in Java technology

    Java Tutorial is a large Chinese-language knowledge base built from years of practical Java development experience. It connects core Java material with Java EE, web applications, servers, build systems, testing, monitoring, and deployment tools. The web section covers Servlets, JSP, filters, listeners, cookies, sessions, Tomcat, Jetty, and Nginx. Development tooling includes Maven, Ant, major IDEs, serializers, template engines, logging libraries, and testing utilities. Framework and middleware coverage includes MyBatis, Spring, Spring Boot, security tools, messaging systems, caches, and distributed services. The repository also links related tutorials and ebook pages, making it a navigable roadmap for learners and working Java engineers.
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  • 22
    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.
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  • 23
    Jaxil (Java XML interface library) is a project for connecting programs together.
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  • 24
    Provides low level classes to facilitate the usage of JDBC and a basic persistence API with no reflection, no cast, thread safe less 'synchronized' blocks and the control of object allocations.
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  • 25
    This project provides an interface to Java expression evaluator software. It does not itself provide expression capabilities but instead provides a common interface.
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