JPA 2 was released in December 2009. The release includes the following new features:
- Standardize useful properties (hints, caching)
- Fill in ORM mapping gaps
- Make object modeling more flexible
- Offer simple cache control abstraction
- Allow advanced locking settings
- Provide more hooks for vendor properties
- Add API for better tooling support
- Enhance JP QL query language
- Support Java API based query language
- Integrate with established validation standards
Mike Keith of Oracle has an excellent presentation on the new features of JPA 2. Mike is an authority on subject and is a member of the JPA JCP Expert Group. Mike is also the author of Pro JPA 2: Mastering the Java Persistence API (Apress).