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Why JPA?

A fundamental question for many Java developers is "Why JPA? Why do I need to know how to use this API when object-relational mapping tools like Hibernate and Toplink are already available?" The answer is that JPA is not a new technology; rather, it has collected the best ideas from existing persistence technologies like Hibernate, TopLink, and JDO. The result is a standardized specification that helps you build a persistence layer that is independent of any particular persistence provider.

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