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eclipsercpnashorn

Make Eclipse RCP package from other bundle available in JavaScript

I have an Eclipse RCP application with the facility to evaluate a JavaScript text on the Nashorn JVM.

Bundle A implements the evaluation of the JS.

The JS script is referencing classes in Bundle B, eg. a enum class. But this Bundle B is not known by Bundle A. And Bundle B loads the classes dynamically by reading an external jar file.

Now when i use importPackage or Java.type i get an ClassNotFoundException.

In Bundle A, i can get retrieve an object from Bundle B from the JAR. With it's classloader i can also access other classes from the JAR.

getBundleBObj().getClass().getClassLoader().loadClass( "my.ClassEnum" );

This succeeds.
Can I use this somehow, to make the package 'my.*' (from Bundle B) be available in the JS?

Solution

  • If you have a java.lang.Class instance, you could expose it as a global variable to script and use "static" property on it.

    In Java:

    // Class yourClassObject = ...

// expose Class object as variable to your script
// "engine" is nashorn engine instance

engine.put("MyClass", yourClassObject);

    In JavaScript:

    var M = MyClass.static;
var obj = new M(); // create object
M.func(); // call static method