[1] NPA is based on the Java Persistence API (JPA), which is the standard persistence API in the Java world.
NPA follows JPA by providing a complete persistence API and a rich set of ORM features.
To use NPA an implementation of the specification is required.
Persistence and ORM vendors can provide their own implementations of NPA.
First implementation, NPA for NHibernate, was released in December 2011.