Introduction to the Solution

Apache OpenJPA is an open-source implementation of the Java Persistence API (JPA) specification. Both OpenJPA and EclipseLink implement standard JPA and also extend it to provide additional features. To migrate an OpenJPA application to EclipseLink, you must switch the persitence provider to EclipseLink and make certain modifications to the application, to account for the differences in OpenJPA and EclipseLink APIs.

Reasons to Migrate

Reasons why you would want to migrate from Hibernate to EclipseLink include:

• Performance and scalability: EclipseLink's caching architecture allows you to minimize object creation and share instances. EclipseLink's caching supports single-node and clustered deployments.

• Support for leading relation databases: EclipseLink continues to support all leading relational databases with extensions specific to each. EclipseLink is also the best ORM solution for Oracle Database.

• A comprehensive persistence solution: While EclipseLink offers industry leading object-relational support, EclipseLink also uses its core mapping functionality to deliver Object-XML (JAXB), Service Data Object (SDO), and Database Web Services (DBWS). Depending on your requirements, you can use one or more of the persistence services based on the same core persistence engine.

• JPA Support: As the JPA 1.0 specification co-leads, Oracle and the EclipseLink/EclipseLink team have been focused on delivering a JPA-compliant solution with supporting integration with Oracle JDeveloper, Oracle ADF, Spring, and the Eclipse IDE (Dali project). Oracle delivered the JPA 1.0 reference implementation and EclipseLink delivers the JPA 2.0 reference implementation.