How to justify why an unchecked cast is okay, regarding Copyable getObjectCopy()

Question

(This is a follow-up to my previous question.)

I have an interface called Copyable, which has a single function

Copyable getObjectCopy();


        

Answer 1

We are in Java 5+ world now! User Generics.

You can change the signature of Copyable to something like:

interface Copyable<T extends Copyable> {
    T getObjectCopy();
}

Now your ValidateValue<L> value would be something like:

puvlic class ValidateValue<L> implements Copyable<ValidateValue<L>> {
    ...
}

and everyone (including the compiler) would be happy!