Could use docs on how to implement a Java interface or class from JavaScript about graaljs HOT 4 OPEN

You can do this with Java.extend (which works similarly to Nashorn), e.g.:

var R = Java.extend(Java.type("java.lang.Runnable"));
var r = new R(function(){print("hello");});
r.run();

or:

var C = Java.extend(Java.type("some.AbstractClass"));
var c = new C({
  someMethod: function() {/*...*/},
  otherMethod: function() {/*...*/},
  toString() {return "MyClass";}
});
c.someMethod();

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Thanks! Could Java interop be extended to do this automatically when the parameter type of the invoked method could be satisfied this way?

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@mikehearn for interfaces that should already be the case, but unfortunately not for classes. We'll consider extending Java interop to do this in the future.

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You're right - I tried it with a simpler case and it worked. It's only the case where there are multiple overloads that doesn't seem to work yet.

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