Java Data Objects (JDO): What It Is and Why It Matters by Ron
Hitchens, Ronsoft Technologies.
JDO is a new standard Java Extension recently finalized by the Java Community
Process or JCP*. JDO is a standardized object persistence API.
With JDO, almost any standard object ( Java class) can be made persistent –
without making any code changes to the class. JDO provides a datastore-agnostic
API for persisting objects. Objects may be stored in a relational database, an
object database, flat file, or other media. The implementation detail of how
object data are stored no longer need concern the object designer (or at least
far less so).
A Persistent Manager is used to maintain the object’s cache and also to
control the store access. There is always a possibility of collision when
more than one persistent manager’s try to grab the same object at the same
For further information on JDO please refer to http://www.jdocentral.com/
* JCP, originally created by Sun Micro Systems,
is an open organization of international Java developers and licensees whose
charter is to develop and revise Java technology specifications, reference
implementations, and technology compatibility kits.