Browse free open source Java Frameworks and projects below. Use the toggles on the left to filter open source Java Frameworks by OS, license, language, programming language, and project status.

  • Stop vibe-debugging. Icon
    Stop vibe-debugging.

    Plug Claude into your app's actual errors.

    AppSignal's MCP server hands Claude, Cursor, or Zed your real errors, traces, and the deploy that shipped them. AI writes the fix; you review the diff.
    Free 30 days.
  • $300 Free Credits to Build on Google Cloud Icon
    $300 Free Credits to Build on Google Cloud

    New to Google Cloud? Get $300 in credits to explore Compute Engine, BigQuery, Cloud Run, Gemini Enterprise Agent Platform, and more.

    Start your next project with $300 in free Google Cloud credit. Spin up VMs, run containers, query petabytes in BigQuery, or build agents with Gemini Enterprise Agent Platform. Once your credits are used, keep building with 20+ always-free tier products including Compute Engine, Cloud Storage, GKE, and Cloud Run functions. No commitment required—just sign up and start building.
    Claim $300 Free
  • 1
    CoDeK - Java Concurrent Development frameworK is a very simple, open-source, academic java library aimed to help the development of Java multi-threading concurrent applications.
    Downloads: 0 This Week
    Last Update:
    See Project
  • 2

    CoSimA+

    The Co-Simulation Adaptation Platform

    The co-simulation adapation platform serves as programming framework and middleware to enable coupling of distributed, heterogeneous numerical models. The framework facilitates the adaptation and integration of new sub-models into a common simulation platform.
    Downloads: 0 This Week
    Last Update:
    See Project
  • 3
    Downloads: 0 This Week
    Last Update:
    See Project
  • 4
    The management of static code is a universal issue for every enterprise applications, this framework tries to address it with a lightweight and simple solution.
    Downloads: 0 This Week
    Last Update:
    See Project
  • Train ML Models With SQL You Already Know Icon
    Train ML Models With SQL You Already Know

    BigQuery automates data prep, analysis, and predictions with built-in AI assistance.

    Build and deploy ML models using familiar SQL. Automate data prep with built-in Gemini. Query 1 TB and store 10 GB free monthly.
    Try Free
  • 5
    The CodeTime platform covers every aspect of parallel software from authoring, through distribution, to run-time. Its goals are: high programmer productivity; write once, run high performance anywhere; and wide acceptance.
    Downloads: 0 This Week
    Last Update:
    See Project
  • 6
    A flexible code generation framework providing the infrastructure for developers to build their own code generators.
    Downloads: 0 This Week
    Last Update:
    See Project
  • 7
    This framework provides the easiest way to build cross platform installers based on Java technologies. Due to its extensible architecture, it can be easily adjusted to fit your needs and allows nice UI interfaces implemented with Groovy or JavaFX.
    Downloads: 0 This Week
    Last Update:
    See Project
  • 8

    Coherent Logic FRED Client

    Java client API for accessing the FRED web services

    ***** WARNING ***** The delivery of the 1.0.3-RELEASE of this framework will be the final source code commit that will be made on SourceForge; all further updates can be found at the following address: https://bitbucket.org/CoherentLogic/coherent-logic-fred-client/ ***** WARNING ***** The FRED Client is a Java-based internal domain-specific language (DSL) for accessing the Federal Reserve Economic Data (FRED) web services complements of the Federal Reserve Bank of St. Louis. The API is designed to work with The Spring Framework and includes several examples to demonstrate how the components fit together. The domain model includes Java Persistence Annotations (JPA) for projects with requirements to persist FRED data in a database. Also included with this API are data access objects to facilitate various persistence operations.
    Downloads: 0 This Week
    Last Update:
    See Project
  • 9
    Coherent Nucleus is a Java classloader implementation which is used to build executable jar files which contain other jar files that need to be included in the application's classpath via the manifest file's Class-Path attribute.
    Downloads: 0 This Week
    Last Update:
    See Project
  • Build Agents and Models on One Platform Icon
    Build Agents and Models on One Platform

    Everything you need to build production-ready agents and models. Access 200+ Google and third-party AI models and tools.

    Gemini Enterprise Agent Platform is Google Cloud's comprehensive platform for developers to build, scale, govern, and optimize agents and models. Choose from Google's most advanced models and third-party models like Anthropic's Claude Model Family.
    Try It Free
  • 10
    Coherent MK is a Java based microkernel framework.
    Downloads: 0 This Week
    Last Update:
    See Project
  • 11
    The Collaborative Editing Framework for XML (CEFX) is a software framework that targets developers who want to either extend an existing or create new XML collaborative real-time editing software easily.
    Downloads: 0 This Week
    Last Update:
    See Project
  • 12
    Combean is a Java framework for mathematical structures and optimization algorithms. Through a set of Java interfaces and JavaBeans-based config, Combean glues optimization codes together - leading to more interoperable, adaptable and flexible solutions.
    Downloads: 0 This Week
    Last Update:
    See Project
  • 13
    This project provides a highly adaptive and easy to use command line option parser for Java applications. Apache CLI Command Line Parser was not satisfiable, so this API was intended to be more "complete" and easier to use than other known libraries.
    Downloads: 0 This Week
    Last Update:
    See Project
  • 14
    Collection of common and utilitarian code for mobile application (J2ME) developers.
    Downloads: 0 This Week
    Last Update:
    See Project
  • 15
    This is a community based open source. These are api sets which can be used for any community applications
    Downloads: 0 This Week
    Last Update:
    See Project
  • 16
    An open-source implementation of a self-contained Java-based component model called CompUnit. CompUnit introduces users to the software component lifecycle without requiring proprietary technology or being dependent upon a number of external projects.
    Downloads: 0 This Week
    Last Update:
    See Project
  • 17
    Developed in KBQuest Ltd, Compass framework is an architectural pattern for web application. It provides guidelines for developers to avoid misuse of frameworks.
    Downloads: 0 This Week
    Last Update:
    See Project
  • 18
    Compiere MFG+SCM Manufacturing Extended System (MES). Include Shop Floor Control, Supply chain management, Quality management, modbus interface, iReport barcode extension etc. Support batch and on demand manufacturing. Works alone or connected to ERP.
    Downloads: 0 This Week
    Last Update:
    See Project
  • 19
    JavaSever Faces. The ComplexDataTable component JSF component that extends the datatable component. It provides additional feature such as: · A sorting mechanism (Sorting works on any data type) · In-line edit · In-line delete · Add record · Scrolla
    Downloads: 0 This Week
    Last Update:
    See Project
  • 20
    Component

    Component

    A powerful componentized framework

    A powerful componentized framework. A powerful, 100% compatible, AndroidX, Kotlin support and flexible componentized framework. Component 2.x will all use Kotlin, and the annotation driver will be developed using ksp. The workload is huge. Therefore, the official 2.x version will have routine maintenance bugs in 1.9.x after a long time, please rest assured. Early adopters can use it 2.x, please use 1.9.x for stability. Choosing a better, more comprehensive, more stable and more promising framework is what your technical team or technical leader has to do! A powerful componentized framework that pays great attention to the user experience and brings you a different enjoyment in use. The whole design is close to the original, and there is very little invasion of the original code, and the original code is preserved as much as possible.
    Downloads: 0 This Week
    Last Update:
    See Project
  • 21
    Components is a very fast and easy java web framework. The main features are: very strict separation between presentation and controller layers (no more JSP!), ease of use, very fast page rendering, zero-configuration paradigm.
    Downloads: 0 This Week
    Last Update:
    See Project
  • 22
    Components 4 Java
    Components 4 Java is a development tool for Java. It provides a framework to organize different parts of code in loosely coupled components. Those will be sticked together graphically to larger compositions and distributed among Java Archives.
    Downloads: 0 This Week
    Last Update:
    See Project
  • 23
    Comtor commons libs, includes: Logs, Exception handling, number printing, configuration files handling, TCP/UDP Server skel.
    Downloads: 0 This Week
    Last Update:
    See Project
  • 24
    A subset of the TestCon project, ConAn builds on Roast to provide a testing framework for concurrent Java components. For more details on the development of ConAn and TestCon/Crom, see http://longbrothers.net/brad/papers/thesis.pdf
    Downloads: 0 This Week
    Last Update:
    See Project
  • 25

    Concept Framework

    Dynamic Knowledge Repository

    Downloads: 0 This Week
    Last Update:
    See Project