How do I compile in debug mode? (netbeans, java, maven)

Question

I am facing annotation/persistence errors in a project and the persistence library throws a

NullPointerException when trying to resolve the entitie

Answer 1

You would need to set your breakpoints in the org.eclipse.persistence.internal.jpa.metadata.accessors.classes.EntityAccessor class, and that should stop during the start up of your server (which you would need to start in debug mode). This is not really compilation, but just JPA loading its metadata from class annotations. Because your JPA provider's code is not something you can understand easily or modify, I would suggest that instead of debugging you try searching for your specific error on the net and see if somebody else has experienced it (i.e. might be a bug on Eclipse Link), it's common for these libraries to throw uninformative exceptions like a Null Pointer when your entities are not annotated correctly.