Learn CHEERPJ with Real Code Examples

Java bytecode compiled -> Wasm + JS runtime

CJRE loads classes dynamically

DOM canvas used for Swing/AWT rendering

Browser APIs wrapped for Java I/O

JS bridge manages interop and system calls

Swing widgets mapped to HTML canvas

AWT events translated into JS events

Graphics via browser’s 2D APIs

CJRE handles repaint cycles

UI always sandboxed in DOM layer

Bytecode loader + Wasm VM

Canvas-based UI rendering

Event loop mapped from Java -> JS

Virtual filesystem for Java IO

Hybrid Java/Wasm runtime model

Applets migrated to browser

Legacy AWT dashboards

Scientific visualizers

Java-based business CRUD tools

Enterprise internal tooling

Run Java unmodified on the web

Maintain compatibility with JVM semantics

Provide predictable, stable runtime

Convert bytecode to efficient Wasm/JS

Ensure long-term preservation of Java software

Split huge JARs into modules

Enable CDN caching

Lazy-load large assets

Leverage browser caching for Wasm

Optimize class loading order

Prepare JARs

Verify Swing/AWT code paths

Load app with cheerpjInit

Test rendering in browser

Optimize Wasm payload and caching