FrenchAddressListContainer defines @FrenchZipcodeListContainer as a constraint that is validated by FrenchZipcodeConstraintValidator, but that class declares its constraint type parameter as @FrenchZipCode. Because that CV type does not override #init() this presumably works in the RI, and the spec is a bit vague on this point, but the interface definition describes type parameter A as "the annotation type handled by an implementation." The spec section ConstraintValidator resolution algorithm also correlates constraint A to the type parameters of the ConstraintValidators described in the resolution rules. Finally, I don't see anything under "What's new in 2.0" to indicate that this should be a legal constraint definition.