Automatic delegation in Java

I want to add some functionality to the objects that will be generated at run time However, the interface of this object is very large (and not under my control) I want to wrap the object in my own class, which adds the functions I want and delegates the standard interface functions to the original object - is there a way to do this in Java without creating a line of copy and paste methods in the delegate method interface for each?

What I want to avoid:

class MyFoo implements Foo {
  Foo wrapped;

  void myMethod() { ... }

  void interfaceMethod1() wrapped.interfaceMethod1();
  int interfaceMethod2() wrapped.interfaceMethod2();
  // etc etc ...
}

What do I prefer:

class MyFoo implements Foo {
  Foo wrapped;

  void myMethod() { ... }

  // automatically delegate undefined methods to wrapped object
}

Solution

It sounds like you need a dynamic proxy and only intercept the methods you want to override

(my focus)

By implementing invocationhandler, you only need to create a method that receives every call on the object (in fact, you have described it above)