Java Data Objects (JDO) is a specification from Sun Microsystems for the transparent persistence of Java objects to any transactional data store. This document provides an overview of JDO. The information presented applies to all JDO implementations, unless otherwise noted.
This document is intended for developers who want to learn about JDO in order to use it in their applications. It assumes that you have a strong knowledge of Java and object-oriented concepts, and a familiarity with the eXtensible Markup Language (XML). This document does not, however, assume any experience with database programming or the manipulation of persistent data in general.
If your goal is to understand every nuance of JDO, then you should skip this document and go directly to the official JDO specification, available from Sun Microsystems.