® Java SE 8 Programmer Scott Selikoff Jeanne Boyarsky Senior Acquisitions Editor: Kenyon Brown Development Editor: David Clark Technical Editors: Janeice DelVecchio, Elena Felder Production Editor: Rebecca Anderson Copy Editor: Judy Flynn Editorial Manager: Mary Beth Wakefield Production Manager: Kathleen Wisor Executive Editor: Jim Minatel Book Designer: Judy Fung and Bill Gibson Proofreader: Nancy Carrasco Indexer: Ted Laux Project Coordinator, Cover: Brent Savage Cover Designer: Wiley Cover Image: ©Getty Images Inc./Jeremy Woodhouse Copyright © 2017 by John Wiley & Sons, Inc., Indianapolis, Indiana Published simultaneously in Canada ISBN: 978-1-119-36339-2 ISBN: 978-1-119-36336-1 (ebk.) ISBN: 978-1-119-36340-8 (ebk.) 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If this book refers to media such as a CD or DVD that is not included in the version you purchased, you may download this material at http://booksupport.wiley.com. For more information about Wiley products, visit www.wiley.com. Library of Congress Control Number: 2017931099 TRADEMARKS: Wiley, the Wiley logo, and the Sybex logo are trademarks or registered trademarks of John Wiley & Sons, Inc. and/or its affiliates, in the United States and other countries, and may not be used without written permission. Java is a registered trademark of Oracle America, Inc. All other trademarks are the property of their respective owners. John Wiley & Sons, Inc. is not associated with any product or vendor mentioned in this book. To the new little bundle of joy my wife is carrying. — Scott Remembering Einstein and CV in same year. Congrats 694! — Jeanne Acknowledgments Scott and Jeanne would like to thank numerous individuals for their contribution to this book. Thank you to David Clark for guiding us through the process and making the book better in so many ways. Thank you to Janeice DelVecchio for being our technical editor as we wrote this book. Janeice pointed out many subtle errors in addition to the big ones. And thank you to Elena Felder for being our technical proofreader and finding the errors that we managed to sneak by Janeice. This book also wouldn’t be possible without many people at Wiley, including Kenyon Brown, Rebecca Anderson, Judy Flynn, Nancy Carrasco, and so many others. Scott could not have reached this point without the help of a small army of people, led by his perpetually understanding wife, Patti, the most wonderful mother their twin daughters, Olivia and Sophia, could ask for. Professors Johannes Gehrke and John H. Hubbard of Cornell University always believed in him and knew he would excel in his career. Scott would like to extend his gratitude to his wonderfully patient co-author Jeanne, on this their third book. “I don’t know how she puts up with me, but I’m glad she does and thrilled at the quality of books we produce.” A big thanks to Matt Dalen, who has been a great friend, sounding board, and caring father to the wonderfully sweet Olivia Dalen. Joel McNary introduced Scott to CodeRanch.com and encouraged him to post regularly, a step that changed his life. Finally, Scott would like to thank his mother and retired teacher, Barbara Selikoff, for teaching him the value of education and his father, Mark Selikoff, for instilling in him the benefits of working hard. Jeanne would personally like to thank everyone at CodeRanch.com who asked and responded to OCA and OCP questions and comments about our first two books. Having dialog with the readers made this book even stronger. Jeanne would like to thank the members of FIRST robotics FRC team 694 in addition to FTC teams 310 and 479 for their support. Your questions make it so she can never forget what new learners are thinking. Go StuyPulse! Jeanne would also like to thank Onur Otlu and Thomas Campos for the feedback on some localization questions. Finally, Jeanne would like to thank Scott for being a great co-author and “not getting tired of me.” Last but not least, both Scott and Jeanne would like to give a big thank you to the readers of our OCA 8 and OCP 8 books. Hearing from all of you who enjoyed the book and passed the exam is a great feeling. We’d also like to thank those who pointed out errors and made suggestions for improvements in our OCP book. As of December 2016, the top three were Guillaume Bailly, Thalita Vergilio, and Sébastien Canonica. We also would like to thank Olivier Chalet, Mihaela Hetea, Peter Deak, Anton Shaikin, Ramya R, Tim Moroz, Aurelien Gamet, Javid Azimli, Salim Rahal, and Sander Wamelink. About the Authors Scott Selikoff is a professional software consultant, author, and owner of Selikoff Solutions, LLC, which provides software development solutions to businesses in the tri- state New York City area. Skilled in a plethora of software languages and platforms, Scott specializes in full-stack database-driven systems, cloud-based applications, and service- oriented architectures. A native of Toms River, New Jersey, Scott achieved his Bachelor of Arts from Cornell University in Mathematics and Computer Science in 2002, after three years of study. In 2003, he received his Masters of Engineering in Computer Science, also from Cornell University. As someone with a deep love of education, Scott has always enjoyed teaching others new concepts. He’s given lectures at Cornell University and Rutgers University, as well as conferences including the Server Side Java Symposium. Scott lives in New Jersey with his loving wife, Patti; amazing twin toddler daughters, Olivia and Sophia; and two very playful dogs, Webby and Georgette. You can find out more about Scott at http://www.linkedin.com/in/selikoff. Jeanne Boyarsky has worked as a Java developer for over 14 years at a bank in New York City where she develops, mentors, and conducts training. Besides being a senior moderator at CodeRanch.com in her free time, she works on the forum’s code base. Jeanne also mentors the programming division of a FIRST robotics team, where she works with students just getting started with Java. Jeanne got her Bachelor of Arts degree in 2002 in Computer Science and her Masters in Computer Information Technology in 2005. She enjoyed getting her Masters degree in an online program while working full time. This was before online education was cool! Jeanne is also a Distinguished Toastmaster and a Scrum Master. You can find out more about Jeanne at https://coderanch.com/wiki/660334. Scott and Jeanne are both moderators on the CodeRanch.com forums, and they can be reached there for questions and comments. They also co-author a technical blog called Down Home Country Coding at http://www.selikoff.net. In addition to this book, Scott and Jeanne are also the authors of OCA Oracle Certified Associate Java SE 8 Programmer I Study Guide (Sybex, 2015) and OCP Oracle Certified Professional Java SE 8 Programmer II Study Guide (Sybex, 2016). More recently, these two books have been combined into the single release OCA / OCP Java SE 8 Programmer Certification Kit: Exam 1Z0-808 and Exam 1Z0-809 (Sybex 2016). Contents Acknowledgments About the Authors Introduction Choosing an Exam Who Should Buy This Book How This Book Is Organized Reviewing Exam Changes Ready to Take the Exam Need More Help Preparing? Bonus Contents Part I OCA Chapter 1 Java Basics Chapter 2 Working with Java Data Types Chapter 3 Using Operators and Decision Constructs Chapter 4 Creating and Using Arrays Chapter 5 Using Loop Constructs Chapter 6 Working with Methods and Encapsulation Chapter 7 Working with Inheritance Chapter 8 Handling Exceptions Chapter 9 Working with Selected Classes from the Java API Chapter 10 OCA Practice Exam Part II OCP Chapter 11 Java Class Design Chapter 12 Advanced Java Class Design Chapter 13 Generics and Collections Chapter 14 Lambda Built-in Functional Interfaces Chapter 15 Java Stream API Chapter 16 Exceptions and Assertions Chapter 17 Use Java SE 8 Date/Time API Chapter 18 Java I/O Fundamentals Chapter 19 Java File I/O (NIO.2) Chapter 20 Java Concurrency Chapter 21 Building Database Applications with JDBC Chapter 22 Localization Chapter 23 OCP Practice Exam Appendix Answers to Review Questions Chapter 1: Java Basics Chapter 2: Working with Java Data Types Chapter 3: Using Operators and Decision Constructs Chapter 4: Creating and Using Arrays Chapter 5: Using Loop Constructs Chapter 6: Working with Methods and Encapsulation Chapter 7: Working with Inheritance Chapter 8: Handling Exceptions Chapter 9: Working with Selected Classes from the Java API Chapter 10: OCA Practice Exam Chapter 11: Java Class Design Chapter 12: Advanced Java Class Design Chapter 13: Generics and Collections Chapter 14: Lambda Built-in Functional Interfaces Chapter 15: Java Stream API Chapter 16: Exceptions and Assertions Chapter 17: Use Java SE 8 Date/Time API Chapter 18: Java I/O Fundamentals Chapter 19: Java File I/O (NIO.2) Chapter 20: Java Concurrency Chapter 21: Building Database Applications with JDBC Chapter 22: Localization Chapter 23: OCP Practice Exam Advert EULA List of Tables Introduction Table I.1 Table I.2 Table I.3