OCA Java SE 8 Programmer I Exam Guide

427 Pages·2017·50.61 MB·English

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CONTRIBUTORS
About the Authors
Kathy Sierra was a lead developer for the SCJP exam for Java 5 and Java 6. Kathy worked as a Sun
“master trainer,” and in 1997, founded JavaRanch.com (now named Coderanch.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 Oracle’s Java Champions program.
These days, Kathy is developing advanced training programs in a variety of domains (from
horsemanship to computer programming), but the thread that ties all her projects together is helping
learners reduce cognitive load.
Bert Bates was a lead developer for many of Sun’s Java certification exams, including the SCJP for Java
5 and Java 6. Bert was also one of the lead developers for Oracle’s OCA 7 and OCP 7 exams and a
contributor on Oracle’s OCA 8 and OCP 8 exams. He is a forum moderator on Coderanch.com (formerly
JavaRanch.com) and has been developing software for more than 30 years (argh!). Bert is the co-author of
several bestselling Java books, and he’s a founding member of Oracle’s Java Champions program. Now
that the book is done, Bert plans to go whack a few tennis balls around and once again start riding his
beautiful Icelandic horse, Eyrraros fra Gufudal-Fremri.
About the Technical Review Team
This is the fifth edition of the book that we’ve cooked up. The first version we worked on was for Java 2.
Then we updated the book for the SCJP 5, again for the SCJP 6, again for the OCA 7 and OCP 7 exams,
and now for the OCA 8. Every step of the way, we were unbelievably fortunate to have fantastic,
JavaRanch.com-centric technical review teams at our sides. Over the course of the last 14 years, we’ve
been “evolving” the book more than rewriting it. Many sections from our original work on the Java 2
book are still intact. On the following pages, we’d like to acknowledge the members of the various
technical review teams who have saved our bacon over the years.
About the Java 2 Technical Review Team
Johannes de Jong has been the leader of our technical review teams forever and ever. (He has more
patience than any three people we know.) For the Java 2 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 the SCJP 5 Technical Review Team
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!
About the SCJP 6 Technical Review Team
Since the upgrade to the Java 6 exam was like a small surgical strike we decided that the technical
review team for this update to the book needed to be similarly fashioned. To that end we hand-picked an
elite crew of JavaRanch’s top gurus to perform the review for the Java 6 exam.
Our endless gratitude goes to Mikalai Zaikin. Mikalai played a huge role in the Java 5 book, and he
returned to help us out again for this Java 6 edition. We need to thank Volha, Anastasia, and Daria for
letting us borrow Mikalai. His comments and edits helped us make huge improvements to the book.
Thanks, Mikalai!
Marc Peabody gets special kudos for helping us out on a double header! In addition to helping us with
Sun’s new SCWCD exam, Marc pitched in with a great set of edits for this book—you saved our bacon
this winter, Marc! (BTW, we didn’t learn until late in the game that Marc, Bryan Basham, and Bert all
share a passion for ultimate Frisbee!)
Like several of our reviewers, not only does Fred Rosenberger volunteer copious amounts of his time
moderating at JavaRanch, he also found time to help us out with this book. Stacey and Olivia, you have
our thanks for loaning us Fred for a while.
Marc Weber moderates at some of JavaRanch’s busiest forums. Marc knows his stuff and uncovered
some really sneaky problems that were buried in the book. While we really appreciate Marc’s help, we
need to warn you all to watch out—he’s got a Phaser!
Finally, we send our thanks to Christophe Verre—if we can find him. It appears that Christophe
performs his JavaRanch moderation duties from various locations around the globe, including France,
Wales, and most recently Tokyo. On more than one occasion Christophe protected us from our own lack of
organization. Thanks for your patience, Christophe! It’s important to know that these guys all donated their
reviewer honorariums to JavaRanch! The JavaRanch community is in your debt.
The OCA 7 and OCP 7 Team
Contributing Authors
The OCA 7 exam is primarily a useful repackaging of some of the objectives from the SCJP 6 exam. On
the other hand, the OCP 7 exam introduced a vast array of brand-new topics. We enlisted several talented
Java gurus to help us cover some of the new topics on the OCP 7 exam. Thanks and kudos to Tom
McGinn for his fantastic work in creating the massive JDBC chapter. Several reviewers told us that Tom
did an amazing job channeling the informal tone we use throughout the book. Next, thanks to Jeanne
Boyarsky. Jeanne was truly a renaissance woman on this project. She contributed to several OCP
chapters; she wrote some questions for the master exams; she performed some project management
activities; and as if that wasn’t enough, she was one of our most energetic technical reviewers. Jeanne, we
can’t thank you enough. Our thanks go to Matt Heimer for his excellent work on the Concurrent chapter.
A really tough topic nicely handled! Finally, Roel De Nijs and Roberto Perillo made some nice
contributions to the book and helped out on the technical review team—thanks, guys!
Technical Review Team
Roel, what can we say? Your work as a technical reviewer is unparalleled. Roel caught so many
technical errors, it made our heads spin. Between the printed book and all the material on the CD, we
estimate that there are over 1,500 pages of “stuff” here. It’s huge! Roel grinded through page after page,
never lost his focus, and made this book better in countless ways. Thank you, Roel!
In addition to her other contributions, Jeanne provided one of the most thorough technical reviews we
received. (We think she enlisted her team of killer robots to help her!)
It seems like no K&B book would be complete without help from our old friend Mikalai Zaikin.
Somehow, between earning 812 different Java certifications, being a husband and father (thanks to Volha,
Anastasia, Daria, and Ivan), and being a “theoretical fisherman” [sic], Mikalai made substantial
contributions to the quality of the book; we’re honored that you helped us again, Mikalai.
Next up, we’d like to thank Vijitha Kumara, JavaRanch moderator and tech reviewer extraordinaire.
We had many reviewers help out during the long course of writing this book, but Vijitha was one of the
few who stuck with us from Chapter 1 all the way through the master exams and on to Chapter 15. Vijitha,
thank you for your help and persistence!
Finally, thanks to the rest of our review team: Roberto Perillo (who also wrote some killer exam
questions), Jim Yingst (was this your fourth time?), other repeat offenders: Fred Rosenberger,
Christophe Verre, Devaka Cooray, Marc Peabody, and newcomer Amit Ghorpade—thanks, guys!
About the OCA 8 Technical Review Team
Due to “pilot error” on your authors’ part, the members of the review team for this book were asked to
work under a tighter-than-ideal schedule. We owe a huge thanks to our six reviewers for this book, who
leapt to action on short notice and once again made numerous fine contributions to the quality of the book.
As has become “the norm,” all our reviewers are moderators at the finest Java community website in the
whole universe, Coderanch.com.
Our first mention goes to Campbell Ritchie, long-time Coderanch moderator, hiker of steep hills, and,
by our count, most prolific reviewer for this edition. In other words, Campbell found the most errors.
Among other pursuits, Campbell is an expert in both pathology and programming, because…why not?
Every time you read an error-free page, think of Campbell and thank him.
In a virtual tie for second place in the “errors found” competition, we present Paweł Baczyński and
Fritz Walraven. Paweł calls Poland his home and is most proud of his wife, Ania, and kids, Szymek and