Can I prevent an interface from being implemented?

Question

I have the following Situation:

public interface A {
    void doSomethingCool();
}

public interface B extends A {
    void doSomethingVeryBCool();
}
public inte         


        

Answer 1

You cannot directly enforce the interface not being implemented, however you can make the interface package-local:

interface A {...} //no public

This way classes outside that package cannot see the interface.

EDIT: however, this does mean that you cannot do something like

A a = getA();

outside the package because A cannot be resolved.