How do I make a Class extend Observable when it has extended another class too?

Question

I am learning Java and I want to make my class into an observable class.

However I already have it extending another class.

What should I do?

Answer 1

Java doesn't allow multiple inheritance, so there is no direct way to do it. You should consider using a delegate pattern having your main object that delegates his observer behaviour to an another object..

class YourObject extends ItsAncestorClass
{
      private Observer includedObserver;

      public Observer getHisObserver(..)
}

Another approach would be turning the object from which your class is extending to an interface, then you'll be allowed to extend from Observer.