title: Possible to have immutable JPA entities?
body: <p>In our hibernate project, the entities are coded using the java beans pattern.  There's quite a few spots in our code where someone has forgotten a to set a mutator and we get an exception due to a NOT NULL field.  </p>
  
  <p>Is anyone using a builder to construct their entities or making them immutable?</p>
  
  <p>I'm trying to find an effective pattern that is not in the style of the java beans pattern.</p>
  
  <p>Thanks</p>