Topic: Java Data Objects

O'Reilly Network articles about this topic:

Simple Object Persistence with the db4o Object Database (ONJava.com)
Mapping Java objects to relational databases is a difficult task, fraught with perils and gotchas. db4o dodges the issue entirely by providing an object-oriented persistence mechanism that is small, lightweight and efficient. Jim Paterson shows how it works.

Hibernate Your Data (ONJava.com)
Hibernate can persist any kind of Java object, manipulate a hierarchy of objects, handle collections, and work with transactions. Davor Cengija shows you how.

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