Currently the methods for constructor validation can't be invoked passing Constructor<?>:
Type mismatch: cannot convert from Set<ConstraintViolation<capture#2-of ?>> to Set<ConstraintViolation<?>>
This can be avoided by relaxing the method signatures a bit:
<T> Set<ConstraintViolation<T>> validateConstructorParameters(Constructor<? extends T> constructor, Object[] parameterValues, Class<?>... groups); <T> Set<ConstraintViolation<T>> validateConstructorReturnValue(Constructor<? extends T> constructor, Object[] parameterValues, Class<?>... groups);