LuaJ - Creating a Lua function in Java

Question

Is there a way to create a Lua function in Java and pass it to Lua to assign it into a variable?

For example:

• In my Java class:

  private class doSomething extends ZeroArgFunction {
      @Override
      public LuaValue call() {
          return "function myFunction() print ('Hello from the other side!'); end" //it is just an example
      }
  }
  

• In my Lua script:

  myVar = myHandler.doSomething();
  myVar();
  

In this case, the output would be: "Hello from the other side!"

Answer 1

Try using Globals.load() to construct a function from a script String, and use LuaValue.set() to set values in your Globals:

static Globals globals = JsePlatform.standardGlobals();

public static class DoSomething extends ZeroArgFunction {
    @Override
    public LuaValue call() {
        // Return a function compiled from an in-line script
        return globals.load("print 'hello from the other side!'");
    }
}

public static void main(String[] args) throws Exception {
    // Load the DoSomething function into the globals
    globals.set("myHandler", new LuaTable());
    globals.get("myHandler").set("doSomething", new DoSomething());

    // Run the function
    String script = 
            "myVar = myHandler.doSomething();"+
            "myVar()";
    LuaValue chunk = globals.load(script);
    chunk.call();
}