Run a Java library

Use Java classes in JavaScript

1. Include CheerpJ on your page

<script src="https://cjrtnc.leaningtech.com/3.0/cj3loader.js"></script>

2. Initialize CheerpJ and load your Java library

await cheerpjInit();
const cj = await cheerpjRunLibrary("/app/library.jar");

Don’t forget to use the /app/ prefix

It is common for first-time users to forget to add the prefix “/app/” when passing the JAR location to cheerpJRunLibrary().

This will load library.jar from the root of your web server.

3. Call Java from JavaScript

const MyClass = await cj.com.library.MyClass;
const obj = await new MyClass();
await obj.myMethod();

Further reading

• cheerpjRunLibrary reference