EJB 3 entities Tutorial (EJB)
The tutorial introduces the Entity Manager Service which provides methods for persisting, finding, querying, removing and updating entities. It then goes on to show the examples of the EntityManager.persist () and EntityManager.find () methods. The tutorial also introduces the concept of a persistence context, which is the set of managed entity instances. Finally, it states some examples of overriding default rules for mapping entities to relational tables.
