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scalajpype

modify Java/Scala class variables with JPype?

I've been trying to use JPype to interface with Scala, and it's been going well, but I've been having trouble modifying class/object variables. To get the value out of them, you have to invoke them as a function (e.g. myObj.var() might give 5). I haven't been able to figure out how to reassign something to myObj.var, since it is of some JavaBoundMethod type or something like that. Is this possible with JPype?

Solution

  • If the member has really been declared as a var (and not as a val), there should be a method named myObj.var_$eq() which you can invoke.

    This code ...

    class Foo {
  var i: Int = 0
}

    ... ends up like this in the bytecode:

    scala> :javap -s Foo
Compiled from "<console>"
public class Foo {
  public int i();
  public void i_$eq(int);
  public Foo();
}