www.traintelco.com www.traintelco.com Beginning Programming with Java ® FOR DUMmIES ‰ 3RD EDITION www.traintelco.com www.traintelco.com by Barry Burd Author of Java 2 For Dummies Beginning Programming with Java ® FOR DUMmIES ‰ 3RD EDITION www.traintelco.com Beginning Programming with Java ® For Dummies ® , 3rd Edition Published by John Wiley & Sons, Inc. 111 River Street Hoboken, NJ 07030-5774 www.wiley.com Copyright © 2012 by John Wiley & Sons, Inc., Hoboken, New Jersey Published by John Wiley & Sons, Inc., Hoboken, New Jersey Published simultaneously in Canada No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, scanning or otherwise, except as permit- ted under Sections 107 or 108 of the 1976 United States Copyright Act, without either the prior written permission of the Publisher, or authorization through payment of the appropriate per-copy fee to the Copyright Clearance Center, 222 Rosewood Drive, Danvers, MA 01923, (978) 750-8400, fax (978) 646-8600. 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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: 2012934909 ISBN 978-0-470-37174-9 (pbk); ISBN 978-1-118-22014-6 (ePDF); ISBN 978-1-118-23384-9 (ePub); ISBN 978-1-118-25852-1 (eMobi) Manufactured in the United States of America 10 9 8 7 6 5 4 3 2 1 www.traintelco.com About the Author Dr. Barry Burd has an M.S. in Computer Science from Rutgers University and a Ph.D. in Mathematics from the University of Illinois. As a teaching assistant in Champaign-Urbana, Illinois, he was elected ve times to the university- wide List of Teachers Ranked as Excellent by their Students. Since 1980, Dr. Burd has been a professor in the Department of Mathematics and Computer Science at Drew University in Madison, New Jersey. When he’s not lecturing at Drew University, Dr. Burd leads training courses for professional programmers in business and industry. He has lectured at conferences in the United States, Europe, Australia, and Asia. He is the author of several articles and books, including Java For Dummies and Android Application Development All-in-One For Dummies, both published by John Wiley & Sons, Inc. Dr. Burd lives in Madison, New Jersey with his wife and two kids (both in their twenties, and mostly on their own). As an avid indoor enthusiast, Dr. Burd enjoys sleeping, talking, and eating. www.traintelco.com www.traintelco.com Dedication For Harriet, Sam and Jennie, Sam and Ruth, Abram and Katie, Benjamin and Jennie Author’s Acknowledgments Author’s To-Do List, February 13, 2012: Item: Send chocolate to Kelly Ewing — the book’s project editor and copy editor. As anyone who reads Chapter 4 learns, chocolate is one of the most precious commodities on earth. So when I give chocolate, I give it thoughtfully and intentionally. Item: Have a plaque erected in honor of Katie Feltman, your acquisitions editor at Wiley. While you worked on other projects, Katie kept on insisting that you write this book’s third edition. (Sure, you wanted a long vacation instead of another book project, but who cares? She was right; you were wrong.) Item: Send a thank-you note to tech editor John Mueller who helped polish your original work and, miraculously, didn’t make a lot of extra work for you. Item: Recommend your agent Neil Salkind to other computer book authors. If it weren’t for Neil, you’d still be roaming the book exhibits and looking needy at the technology conferences. Item: Visit Frank Thornton, Bonnie Averbach, and Herbert Putz at Temple University. Thank them for steering you to a career as a professor. In any other career, you’d have no time left to write. (And by the way, while you’re in Philly, don’t forget to stop for a cheesesteak.) Item: Send e-mail to Gaisi Takeuti at the University of Illinois, and to William Wisdom and Hughes LeBlanc at Temple University. Thank them for teaching you about Symbolic Logic. It’s made your life as a computer scientist and mathematician much richer. Item: Spend more time with your family. (Remind them that you’re the guy who wandered around the house before you started writing books.) Renew your pledge to clean up after yourself. Don’t be so high-strung and nish each sentence that you start. Remember that you can never fully return the love they’ve given you, but you should always keep trying. www.traintelco.com Publisher’s Acknowledgments We’re proud of this book; please send us your comments at http://dummies.custhelp.com. For other comments, please contact our Customer Care Department within the U.S. at 877-762-2974, outside the U.S. at 317-572-3993, or fax 317-572-4002. Some of the people who helped bring this book to market include the following: Acquisitions and Editorial Project Editor: Kelly Ewing Senior Acquisitions Editor: Katie Feltman Technical Editor: John Mueller Editorial Manager: Jodi Jensen Editorial Assistant: Amanda Graham Sr. Editorial Assistant: Cherie Case Cover Photo: © Javier Pierini / Jupiter Images Cartoons: Rich Tennant (www.the5thwave.com) Composition Services Project Coordinator: Sheree Montgomery Layout and Graphics: Carrie A. Cesavice, Corrie Niehaus, Lavonne Roberts Proofreaders: ConText Editorial Services, Inc., Rebecca Denoncour Indexer: Infodex Indexing Services, Inc. Publishing and Editorial for Technology Dummies Richard Swadley, Vice President and Executive Group Publisher Andy Cummings, Vice President and Publisher Mary Bednarek, Executive Acquisitions Director Mary C. Corder, Editorial Director Publishing for Consumer Dummies Kathleen Nebenhaus, Vice President and Executive Publisher Composition Services Debbie Stailey, Director of Composition Services www.traintelco.com [...]... statement .291 A closer look at the do statement 291 Repeating with Predetermined Values (Java s Enhanced for Statement) 293 Creating an enhanced for loop 293 Nesting the enhanced for loops 295 www.traintelco.com xvi Beginning Programming with Java For Dummies, 3rd Edition Part IV: Using Program Units 301 Chapter 16: Using Loops and Arrays ... Your Code with Tutorials .408 Finding Help on Newsgroups 408 Reading Documentation with Commentary 408 Listen! 409 Opinions and Advocacy .409 Looking for Java Jobs 409 Finding Out More about Other Programming Languages .410 Everyone’s Favorite Sites 410 www.traintelco.com xviii Beginning Programming with Java For Dummies, 3rd Edition. .. every technical book starts with a little typeface legend, and Beginning Programming with Java For Dummies, 3rd Edition is no exception What follows is a brief explanation of the typefaces used in this book: ✓ New terms are set in italics ✓ When I want you to type something short or perform a step, I use bold ✓ You’ll also see this computerese font I use the computerese font for Java code, filenames, web... comparing characters 159 The Remaining Primitive Types 166 www.traintelco.com xiv Beginning Programming with Java For Dummies, 3rd Edition Part III: Controlling the Flow 169 Chapter 9: Forks in the Road 171 Decisions, Decisions! 171 Making Decisions (Java if Statements) 173 Looking carefully at if statements 173 A complete program... your own I even get to tell a few funny stories www.traintelco.com 2 Beginning Programming with Java For Dummies, 3rd Edition How to Use This Book I wish I could say, “Open to a random page of this book and start writing Java code Just fill in the blanks and don’t look back.” In a sense, this is true You can’t break anything by writing Java code, so you’re always free to experiment But I have to be honest... Environment .35 Downloading Eclipse .35 Installing Eclipse 37 Running Eclipse for the first time 38 What’s Next? 46 www.traintelco.com xii Beginning Programming with Java For Dummies, 3rd Edition Chapter 3: Running Programs 47 Running a Canned Java Program 47 Typing and Running Your Own Code .52 Separating your programs... www.traintelco.com 5 6 Beginning Programming with Java For Dummies, 3rd Edition Of course, in print, you can’t see me twisting my head I need some other way of setting a side thought in a corner by itself I do it with icons When you see a Tip icon or a Remember icon, you know that I’m taking a quick detour Here’s a list of icons that I use in this book: A tip is an extra piece of information — something... prepared to skim Chapters 6 through 8 Dive fully into Chapter 9 and see whether it feels comfortable (If so, then read on If not, re-skim Chapters 6, 7, and 8.) ✓ If you feel comfortable writing programs in a language other than Java, then this book isn’t for you Keep this book as a memento and buy my Java For Dummies, 5th Edition, also published by John Wiley & Sons, Inc If you want to skip the sidebars and... mouse www.traintelco.com 3 4 Beginning Programming with Java For Dummies, 3rd Edition On those rare occasions when you need to drag and drop, cut and paste, or plug and play, I guide you carefully through the steps But your computer may be configured in any of several billion ways, and my instructions may not quite fit your special situation So when you reach one of these platform-specific tasks, try following... and all kinds of interesting goodies I added an appendix on this book’s website to help you feel comfortable with Java s documentation I can’t write programs without my Java programming documentation In fact, no Java programmer can write programs without those all-important docs These docs are in web page format, so they’re easy to find and easy to navigate But if you’re not used to all the terminology, . www.traintelco.com www.traintelco.com Beginning Programming with Java ® FOR DUMmIES ‰ 3RD EDITION www.traintelco.com www.traintelco.com by Barry Burd Author of Java 2 For Dummies Beginning Programming with Java ® FOR DUMmIES ‰ 3RD. Dummies Beginning Programming with Java ® FOR DUMmIES ‰ 3RD EDITION www.traintelco.com Beginning Programming with Java ® For Dummies ® , 3rd Edition Published by John Wiley & Sons, Inc. 111. 37 Running Eclipse for the rst time 38 What’s Next? 46 www.traintelco.com Beginning Programming with Java For Dummies, 3rd Edition xii Chapter 3: Running Programs 47 Running a Canned Java Program