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OCP Oracle® Certified Professional Java® SE 11 Developer Practice Tests
Exam 1Z0‐819 and Upgrade Exam 1Z0‐817
Scott Selikoff
Jeanne Boyarsky
Copyright © 2021 by John Wiley & Sons, Inc., Indianapolis, Indiana
Published simultaneously in Canada
ISBN: 978‐1‐119‐69613‐1
ISBN: 978‐1‐119‐69617‐9 (ebk.)
ISBN: 978‐1‐119‐69614‐8 (ebk.)
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For my wife Patti—you put up with me.
—Scott
To Chris for being the first person on earth who knew I'd write a book or seven.
—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, Pete Gaughan, Christine O'Connor, Saravanan Dakshinamurthy, Kim Wimpsett, Evelyn Wellborn, and so many others.
Scott could not have reached this point without his wife, Patti, and family, whose love and support make this book possible. He would like to thank his twin daughters, Olivia and Sophia, and youngest daughter, Elysia, for their patience and understanding, especially when it was “time for Daddy to work in his office!” Scott would like to extend his gratitude to his wonderfully patient co‐author, Jeanne, on this, their seventh book. He doesn't know how she's able to work with him for months at a time, but he's 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 Olivia, Adeline, and newborn Henry. 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 who kept her sane during the COVID‐19 pandemic, especially Dani, Elena, Janeice, Norm, Rodridgo, Scott, and Wendy. Scott was a great co‐author, improving everything Jeanne wrote while writing his own chapters. A big thank‐you to everyone at CodeRanch.com who asked and responded to questions and comments about our books. Another big thank‐you to the NYJavaSig as it transitioned to online. Finally, Jeanne would like to thank all of the new programmers at CodeRanch.com and FIRST robotics teams FRC 694, FTC 310, FTC 479, and FTC 8365 for the reminders of how new programmers and technologists think.
Scott and Jeanne would like to give a big thank‐you to the readers of all our 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