Java Persistence/What is new in JPA 2.0?

The JPA 2.0 specification adds several enhancements to the JPA 1.0 specification including:

• Extended Map support - Support for maintaining a key column for a Basic, Embeddable, or Entity key value in any collection relationship using a Map.
• Derived Identifiers
• Nested embedding
• New collection mappings - Support for collections of Basic or Embeddable types.
• Undirectional OneToMany
• Ordered List mappings - Support for maintaining an index column in any collection relationship using a List.
• Orphan removal - Automatic deletion of objects removed from relationships.
• Pessimistic Locking
• EntityManager API updates
• Cache APIs
• Standard Properties
• Metadata
• Criteria API
• JPQL enhancements

Resources

• JPA 2.0 Spec
• JPA 2.0 Reference Implementation (EclipseLink)
• Eclipse EclipseLink to be JPA 2.0 Reference Implementation
• JPA 2.0 Examples