SCJP Sun Certified Programmer for Java 5 Study Guide (Exam 310-055) (Certification Press)

Kathy Sierra

Bert Bates

McGraw-Hill/Osborne

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Acquisitions Editor Timothy Green

Project Editor Jody McKenzie

Acquisitions Coordinator Jennifer Housh

Proofreader Linda Medoff

Indexer Jack Lewis

Composition Bert BatesMidori Batten

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Cover Series Design Peter Grame

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To the Java Community.

Contributors

About the Authors

Kathy Sierra was a lead developer for the SCJP exam for Java 5. Sierra worked as a Sun "master trainer," and in 1997, founded Javaranch.com, the world's largest Java community website. Her bestselling Java books have won multiple Software Development Magazine awards, and she is a founding member of Sun's Java Champions program.

Bert Bates was a lead developer for many of Sun's Java certification exams including the SCJP for Java 5. He is also a forum moderator on Javaranch.com, and has been developing software for more than 20 years. Bert is the co-author of several bestselling Java books, and he's a founding member of Sun's Java Champions program.

About the Technical Review Team

Johannes de Jong has been the leader of our technical review teams for ever and ever. (He has more patience than any three people we know.) For this book, he led our biggest team ever. Our sincere thanks go out to the following volunteers who were knowledgeable, diligent, patient, and picky, picky, picky!

Rob Ross, Nicholas Cheung, Jane Griscti, Ilja Preuss, Vincent Brabant, Kudret Serin, Bill Seipel, Jing Yi, Ginu Jacob George, Radiya, LuAnn Mazza, Anshu Mishra, Anandhi Navaneethakrishnan, Didier Varon, Mary McCartney, Harsha Pherwani, Abhishek Misra, and Suman Das.

About LearnKey

LearnKey provides self-paced learning content and multimedia delivery solutions to enhance personal skills and business productivity. LearnKey claims the largest library of rich streaming-media training content that engages learners in dynamic media-rich instruction complete with video clips, audio, full motion graphics, and animated illustrations. LearnKey can be found on the Web at www.LearnKey.com.

Technical Review Superstars

We don't know who burned the most midnight oil, but we can (and did) count everybody's edits—so in order of most edits made, we proudly present our Superstars.

Our top honors go to Kristin Stromberg—every time you see a semicolon used correctly, tip your hat to Kristin. Next up is Burk Hufnagel who fixed more code than we care to admit. Bill Mietelski and Gian Franco Casula caught every kind of error we threw at them—awesome job, guys! Devender Thareja made sure we didn't use too much slang, and Mark Spritzler kept the humor coming. Mikalai Zaikin and Seema Manivannan made great catches every step of the way, and Marilyn de Queiroz and Valentin Crettaz both put in another stellar performance (saving our butts yet again). Marcelo Ortega, Jef Cumps (another veteran), Andrew Monkhouse, and Jeroen Sterken rounded out our crew of superstars—thanks to you all. Jim Yingst was a member of the Sun exam creation team, and he helped us write and review some of the twistier questions in the book (bwa-ha-ha-ha).

As always, every time you read a clean page, thank our reviewers, and if you do catch an error, it's most certainly because your authors messed up. And oh, one last thanks to Johannes. You rule dude!

Acknowledgements

Kathy and Bert would like to thank the following people:

• All the incredibly hard-working folks at Osborne: Tim Green, Jim Kussow, Jody McKenzie, and Jennifer Housh for all their help, and for being so responsive and patient—well, okay, not all that patient—but so professional and the nicest group of people you could hope to work with.

• To our saviors Solveig Haugland and Midori Batten, for coming to our rescue when we were really in a bind!

• Some of the software professionals and friends who helped us in the early days: Tom Bender, Peter Loerincs, Craig Matthews, Dave Gustafson, Leonard Coyne, Morgan Porter, and Mike Kavenaugh.

• Above all, the wonderful and talented Certification team at Sun Educational Services, Steve ("Goose") Moore, and the most persistent get-it-done person we know, Evelyn Cartagena (congrats on being a new Mom Evelyn).

• Our great friends and gurus, Bryan Basham, Kathy Collina, and Simon Roberts.

• To Eden and Skyler, for being horrified that adults—out of school—would study this hard for an exam.

• To the Javaranch Trail Boss Paul Wheaton, for running the best Java community site on the Web.

• To all the past and present Sun Ed Java instructors for helping to make learning Java a fun experience including (to name only a few): Alan Petersen, Jean Tordella, Georgianna Meagher, Anthony Orapallo, Jacqueline Jones, James Cubeta, Teri Cubeta, Rob Weingruber, John Nyquist, Asok Perumainar, Steve Stelting, Kimberly Bobrow, Keith Ratliff, and the most caring and inspiring Java guy on the planet, Jari Paukku.

• To Darren and Mary, thanks for keeping us sane and for helping us with our new furry friends Andi and Kara.

• Finally, to Eric and Beth Freeman for your continued inspiration.