Jeena Jeen wrote: Soon I am going to start work on a new project for which some part is in Hibernate. So do you think if I only read about JPA then it should sufficient?
Yup.
There is a diference in using JPA and Hibernate (as implementation only) or using Hibernate only.
With the first you would do all action through the EntityManager, the second you would use the Hibernate Session.
The first advantage is that you will reduce the coupling between your application an the Hibernate ( in cause you want to change the implementation this would be easier ).
Hibernate has a lot of annotations that is not found in the JPA, but to me they are not necessary.
If you want to learn about the Hibernate itself I have no book indications so far, the Pro JPA 2 book talks about JPA with any implementation (like Hibernate, Eclipselink, Batoo).
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