I want multiple return types, I think....

Question

I'm working on a system where I want a factory method that returns AWT Components that implement some interface X. I can't simply use an abstract class Y that extends component and implements X because the components that I want to have implement X subclass things like JLabels and JPanels. Furthermore, I don't really care about a type Y, as it would be meaningless in my system other than being the combination of these two types.
This is a language issue because what I really want my function to look like is:
public {Component, X} createXComponent(...) {
  return new (thing that is both Component and implements X);
}where [Component, X] indicates the return type. Assuming that the abstract class is not an option, is there any way that I can design around this, and if not, might this sort of scenario possibly warrant a future langauge extension? It could come in the form of a type declaration that wasn't a class in itself, but indicated a named combination of 0 or 1 classes and some number of interfaces.
Thoughts?
Ben Kuhn

Answer 1

I think the answer to my question at this point is
that no, there's no convenient alternative design
solution, and I've settled on using a sig. that
returns X (and casting to component as needed), but I
was looking for a more semantically correct solution.That seems like the best way to do it. When needed you can use the instanceof operator to see if the cast will be allowed.
Another option may be to have your interface X include a method called
   public Component getComponent();The implementation in the concrete classes would be something like this:
   public Comonent getComponent() {
      return this;
   }Then if you wanted the Component view of the object you could call getComponent() rather than casting.
Just a thought.