I highly recommend this book.
Positioned as a layer between the application and the database, Hibernate is a powerful object/relational persistence and query service for Java. It takes care of automating a tedious task: the manual bridging of the gap between object oriented code and the relational database. Hibernate Quickly gives you all you need to start working with Hibernate now.
The book focuses on the 20% you need 80% of the time. The pages saved are used to introduce you to the Hibernate "ecosystem": how Hibernate can work with other common development tools and frameworks like XDoclet, Struts, Webwork, Spring, and Tapestry.
The book builds its code examples incrementally, introducing new concepts as it goes. It covers Hibernate's many, useful configuration and design options, breaking a complex subject into digestible pieces. With a gradual "crawl-walk-run" approach, the book teaches you what Hibernate is, what it can do, and how you can work with it effectively.
Patrick Peak is the CTO of a firm that emphasizes open source frameworks and tools for competitive advantage. He lives in Arlington, Virginia.
Nick Heudecker has large scale development experience with projects for Fortune 500 clients, the media, and government. He lives in Chicago, Illinois.