JPA, part of the Java EE EJB 3.0 specification, greatly simplifies Java persistence. It provides an object-relational mapping approach that allows you to declaratively define how to map Java objects to relational database tables in a standard, portable way. JPA works both inside a Java EE application server and outside an EJB container in a Java Standard Edition (Java SE) application.
With OEPE, you can create a persistence layer that uses EJB 3.0 JPA.
For more information, see Object-Relational Mappings Support.