title: Validation is skipped when constraints are only in parent class
body: <p>I am using MOXy as JAXB provider along with Bean Validation. </p>
  
  <p>I'm trying to validate a class where only parent fields are annotated with constraints.</p>
  
  <p>I can see that MOXy is skipping validation for this class, probably it is not looking into the parent class.</p>
  
  <p>Can you advise on how to overcome this?</p>