title: Eclipse JPA structure view, detail view, and persistence.xml editor not working?
body: <p>Eclipse has pretty cool JPA Structure and JPA Detail views along with a persistence.xml editor and a JPA perspective.  However, I cannot seem to get them to "turn on".  I had them all working several months ago, but something must have changed.</p>
  
  <p>Any tips as to what secret sauce is needed to get them working again?</p>