Learn CHEERPJ with Real Code Examples

Updated Nov 25, 2025

Introduction & Fundamentals Setup & Configuration Architecture & Deep Internals Performance & Security Development Workflow Learning & Career Growth Business & Strategy Examples

Monetization

Legacy app migration services

SaaS delivery of Java desktop apps

Enterprise web tools

Education software preservation

Commercial internal dashboards

Future Roadmap

Better performance for Swing

Smaller Wasm payloads

Improved debugging tools

Faster class loading

Enterprise optimizations

When Not To Use

High-performance gaming

Real-time graphics rendering

Apps requiring JVM-level performance tuning

Projects better rewritten in JS/TS

Tiny footprint browser widgets

Final Summary

CheerpJ allows unmodified Java applications to run inside modern browsers.

It converts Java bytecode into WebAssembly and JS.

Strong support for Swing/AWT and enterprise legacy apps.

Ideal for preserving old Java tools and migrating applets.

A practical solution for browser-based JVM compatibility.

Faq

Can CheerpJ run any Java app?

Most - especially Swing, AWT, and console apps.

Does it require rewriting Java?

No - it runs unmodified Java bytecode.

Is performance like a JVM?

No - slower due to browser constraints.

Does it support JavaFX?

Limited - Swing/AWT best supported.

Can it access local files?

Only via virtual filesystem.