CheerpJ 4.0：用于浏览器的 WebAssembly JVM，现在支持 Java 11 和 JNI

CheerpJ 4.0 Overview: Announced today, it's the latest major release of CheerpJ. Supports both Java 8 and Java 11, with Java 17 support planned for CheerpJ 5.0. Comes with improved mobile usability, WebAssembly JNI module support, and performance enhancements.
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What can CheerpJ do:
- Running large-scale Swing / AWT applications: Can run existing Java applications from unmodified JARs without recompilation. Supports AWT and Swing-based applications, and is mobile-ready. Easy to run with just three API calls.
- Using Java libraries as part of Web Applications: Allows using Java libraries from JavaScript using async/await approach (Library Mode). Provides extensive Java access features. Useful for migrating large-scale Java apps to native web apps.
- Running legacy Java Applets and Java Web Start: Built specialized browser extensions (CheerpJ Applet Runner and CheerpJ JNLP Runner) to run these applications without manual integration. Popular with hundreds of thousands of users.
How does CheerpJ work: A Java Virtual Machine in WebAssembly for the browser that JIT-compiles Java bytecode into JavaScript. Has a WebAssembly JVM and JIT compiler, a complete OpenJDK, and a virtualized system layer.
Demo: Unmodified Minecraft in the browser: Created Browsercraft by fetching the original client.jar from Mojang servers and using JNI WebAssembly modules for LWJGL and gl4es. A stress test for CheerpJ with recent performance improvements.
What’s next:
- Support for Java 17 as part of CheerpJ 5.0, with implementation at the prototypical stage.
- Support for JavaFX / SWT using WebAssembly JNI modules and compiling C++ to WebAssembly.
- General availability for JNI headers and libraries.
Licensing: Commercial software. Free for FOSS projects, personal projects, and one-person companies. Affordable and transparent licensing for small businesses. Enterprise licensing and support available with discounts for non-profits and educational institutions.
Try it out and join the community: Extensively documented. Join Discord for questions and support. Hosting the first CheerpJ Hackathon between September and October 2025 with a £500 prize.
About Leaning Technologies: An international team of WebAssembly hackers based in Amsterdam (NL) and Leeds (UK) building CheerpJ with passion. Star CheerpJ on GitHub.