Hello,

From what I understood, Hibernate3 can be used as a JPA implementation. But JPA spec seems to be a subset of Hibernate 3 features.

What features in Hib3 are missing from JPA ?
May I code 80% of my application using JPA and the remaining with Hib3 specific features ?
How do I know when I'm coding something standard (i.e. JPA) and when I'm coding sthing specific (Hib3) ?

Thank you

Well, typically, the Criteria API and filters.


I don't see any impossibility to do so. The majority of your code will deal with javax.persistence.EntityManager, while some portion will use a org.hibernate.Session...
However, while 80% of your application will not depend on your ORM, the remaining 20% will.


In order to use Hibernate's JPA implementation, you will have to use the Hibernate Annotations and Hibernate Entity Manager extensions.
When using JPA, you only deal with classes from the ""javax.persistence" package (EntityManager, etc.) and your code is indepedent from the JPA implementation.
Whenever you're using "org.hibernate" classes (Session, etc.), you're in Hibernate.

Hope this helps

A simple means of accessing Hibernates Native API while using JPA is to cast the EntityManager to the HibernatEntityManager to access the Hibernate Session:



Ryan-

Or even easier, use:

Session s = (Session) em.getDelegate();

Even better! Thanks for the tip.

Ryan-