title: How much business logic should Value objects contain?
body: <p>One mentor I respect suggests that a simple bean is a waste of time - that value objects 'MUST' contain some business logic to be useful. </p>
  
  <p>Another says such code is difficult to maintain and that all business logic must be externalized. </p>
  
  <p>I realize this question is subjective. Asking anyway - want to know answers from more perspectives.</p>