Hi, 

I'm doing some tests with bean validation, and i have some doubts about the behavior of method constraints on inheritance hierarchies.

The specification tells about Liskov substitution, on method constraints within inheritance hierarchies, but i made the test bellow with 

the reference implementation ( hiberante validator 5.1 ), and not understand if this is a bug in implementation or my misunderstanding the specification.

public interface Foo {

     public void doStuff(@NotNull String v);

}

@Named

public class Bar implements Foo {

     public void doStuff(String v) {}

}

Calling bar.doStuff(null), the validation is not fired.

But if i changed Foo interface to an abstract class, and made Bar extends it, the validation is fired and a ConstraintViolationException is propagated.

The test was done with cdi.

What should be the appropriate behavior?