CheerpJ
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CheerpJ
  1. Overview
  2. Getting started
    1. Run a Java Application
    2. Run a Java Applet
    3. Run a Java Library
    4. Run a JNLP
  3. Guides
    1. Intercept external commands
    2. Networking
    3. Resource preloading
    4. Basic Server Setup
    5. Debugging CheerpJ
    6. Filesystem
    7. Implementing Native Libraries
    8. Implementing Native Methods
    9. Library mode
  4. Reference
    1. cheerpjInit
    2. cheerpjRunMain
    3. cheerpjRunJar
    4. cheerpjRunLibrary
    5. cheerpjCreateDisplay
    6. cjFileBlob
    7. cheerpOSAddStringFile
    8. cheerpOSRemoveStringFile
    9. cjGetRuntimeResources
    10. cjGetProguardConfiguration
    11. CJ3Library
  5. Tutorials
    1. Run a Java App in the Browser (SwingSet3)
    2. Run a Java Applet in the Browser (FoilSim)
    3. Run JNLP Apps in the Browser
    4. Swing Browser (Networking)
    5. Server-Client (Networking)
    6. Java and JavaScript Interoperability
  6. Explanation
    1. Files and filesystems
    2. Architecture
  7. Frequently Asked Questions
  8. Migration from CheerpJ 2
  9. Changelog
  10. Licensing
  11. Open Source Copyright Notices

Guides

  • Intercept external commands
    How to intercept external system commands that are executed in a Java application
  • Networking
    Networking with CheerpJ
  • Resource preloading
    Improves application startup time
  • Basic Server Setup
    How do serve your own Java application with CheerpJ
  • Debugging CheerpJ
    How to properly debug CheerpJ in the browser
  • Filesystem
    Interacting with the virtual filesystem in CheerpJ
  • Implementing Native Libraries
    Java Native Interface (JNI) with CheerpJ
  • Implementing Native Methods
    Java Native Interface (JNI) with CheerpJ
  • Library mode
    Use Java libraries in JavaScript
Leaning Technologies
UK Business Tech Awards 2022 Finalist National Technology Awards 2022 Winner

Technology

  • Cheerp
  • CheerpJ
  • CheerpX
  • CheerpX for Flash
  • BrowserPod

Browser extensions

  • CheerpJ Applet Runner
  • CheerpJ JNLP Runner

Resources

  • Documentation
  • Blog
  • GitHub
  • Contributing

Company

  • About us
  • News
  • Privacy policy
  • Careers

© 2026 Leaning Technologies . All rights reserved.

Cheerp is a registered trademark of Leaning Technologies. The Cheerp, CheerpJ, and CheerpX logos are based on the HTML5 logo by W3C (license)