Using and Understanding Java Data Objects

DAVID EZZIO

Copyright 2003 by David Ezzio

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ISBN (pbk): 1-59059-043-0

Printed and bound in the United States of America 12345678910

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Technical Reviewers: Regis Le Brettevillois, John Mitchell, Abe White

Editorial Directors: Dan Appleman, Gary Cornell, Martin Streicher, Karen Watterson, John Zukowski

Assistant Publisher: Grace Wong

Project Manager: Tracy Brown Collins

Copy Editor: Ami Knox

Production Editor: Julianna Scott Fein

Composition: Susan Glinert

Indexer: Valerie Robbins

Proofreader: Elizabeth Berry

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The source code for this book is available to readers at http://www.apress.com in the Downloads section.

This book is dedicated to my wife, Theresa, and our daughters, Pearly and Sarah.

A man is a fish who swims in the sea of a woman's love.

About the Author

David Ezzio wrote his first application, which analyzed French elections, for a college professor in the sixties. After a detour through philosophy and other pursuits, he has worked with software teams building desktop applications, character recognition software, and Internet-related software. He has worked exclusively with Java since 1997 and is a Sun Certified Java Developer. Dave founded his consulting practice, Yankee Software, in 1988 and helped found MaineJUG in 2001. He is a member of the JDO 1.0 maintenance group.

Dave holds a bachelor's degree in mathematical logic from Yale University and a master's degree in philosophy from the University of Chicago. In his free time, Dave hikes, rides his bicycle, reads history, and sails his Laser Tippity. An occasional cook, he currently takes pride in his popovers. He lives in Maine. His e-mail address is <[e-mail]>.

About the Technical Reviewers

Regis Le Brettevillois has cofounded LIBeLIS (Paris, France), one of the JDO vendors, where he is acting as CTO. Before founding LIBeLIS, he was senior consultant for Versant, an ODBMS vendor. He has been in charge of Java/Database architecture for customers like Banque Nationale de Paris and France Telecom. Before this, he was consultant and R&D engineer for LM Informatique (Paris), OTI (Ottawa, Canada), and Andersen Informatique (Paris). Regis has been involved in various Java and Smalltalk projects in which object distribution and persistence technologies were strategic. Regis has a postgraduate diploma in computer science from the University of Nantes.

John Mitchell is the founder of Non.net—a Technological Business Risk Management™ consulting practice. Along with developing and rescuing distributed enterprise systems, John advises investors and executives on technology and high-tech companies. Over the past 15 years, John has been the CTO of ElasticMedia, HealthLogic.com, jGuru, and the MageLang Institute. He cowrote Making Sense of Java: A Guide for Managers and the Rest of Us and created the "Q&A" and "Tips & Tricks" columns at JavaWorld. John is writing books on distributed systems, software development, and technological risk management.

Abe White is a senior software architect at SolarMetric (http://www.solarmetric.com) and is the original author of Kodo JDO (http://www.solarmetric.com/Software/Kodo_JDO/). He became interested in JDO while working in research and development at TechTrader, where he specialized in object/relational mapping, object/XML mapping, and Java Enterprise technologies. Abe also has extensive experience with Java byte code manipulation, and is the creator of the open source Serp Bytecode Toolkit (http://serp.sourceforge.net). Abe was a founder of The Basement, a nonprofit entity based at Dartmouth College, his alma mater. The Basement creates Web-based solutions for academia. Abe is a member of the JDO Expert Group.

Acknowledgments

A lot of people had a hand in making this book. I thank all the folks at Apress who pulled everything together. Particular thanks to Ami Knox, the copy editor; Tracy Brown Collins and Sofia Marchant, the tag-team project managers; John Zukowski, the Java editor and Visio wizard; and Gary Cornell, the publisher.

I thank Craig Russell, the JDO specification lead, and the other members of the JDO maintenance group for answering my questions and responding to my suggestions.

I thank my technical reviewers, Abe White, Regis Le Brettevillois, and John D. Mitchell. They labored long and hard, and their many comments made this book better than it would otherwise have been.

For an author, a book is more than a business proposition. It is a labor of love and passion. I thank all those who encouraged me in my work. In particular, I thank my children, Pearly and Sarah, who frequently gave me impromptu encouragement. Their love of books inspired me. I thank my father, James Ezzio, and his wife, Mary, for their kind words and generous deeds. Finally, I thank my wife, Theresa. Her confidence in my abilities made the book possible.