Complete Java 2 Certification Study Guide Fifth Edition Copyright ©2005 SYBEX Inc., 1151 Marina Village Parkway, Alameda, CA 94501. www.sybex.com COPYING PROHIBITED © Copyright ©2005 SYBEX Inc., 1151 Marina Village Parkway, Alameda, CA 94501. www.sybex.com COPYING PROHIBITED © Wiley Publishing, Inc. Complete Java ® 2 Certification Study Guide Fifth Edition Philip Heller Simon Roberts Copyright ©2005 SYBEX Inc., 1151 Marina Village Parkway, Alameda, CA 94501. www.sybex.com COPYING PROHIBITED © Publisher: Neil Edde Acquisitions and Developmental Editor: Jeff Kellum Production Editor: Katherine Perry Technical Editor: James Nuzzi Copyeditor: Linda S. Recktenwald Compositor: Laurie Stewart, Happenstance Type-O-Rama Graphic Illustrator: Jeffrey Wilson, Happenstance Type-O-Rama CD Coordinator: Dan Mummert CD Technician: Kevin Ly Proofreaders: Jim Brook, Jennifer Larsen, Nancy Riddiough Indexer: Ted Laux Book Designer: Judy Fung Cover Designer: Archer Design Cover Illustrator/Photographer: Photodisk and Victor Arre Copyright © 2005 by Wiley Publishing, Inc., Indianapolis, Indiana First edition copyright © 1999 SYBEX, Inc. Second edition copyright © 2000 SYBEX, Inc. Third edition copyright © 2002 SYBEX, Inc. Fourth edition copyright © 2003 SYBEX, Inc. 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The author, editors, and technical reviewers have worked hard to ensure that the updated fifth edition of the Complete Java 2 Certification Study Guide you hold in your hands is com- prehensive, in-depth, and pedagogically sound. We’re confident that this book will exceed the demanding standards of the certification marketplace and help you, the Java certification can- didate, succeed in your endeavors. As always, your feedback is important to us. If you believe you’ve identified an error in the book, please visit the Customer Support section of the Wiley web site. And if you have general comments or suggestions, feel free to drop me a line directly at nedde@wiley.com. At Sybex we’re continually striving to meet the needs of individuals preparing for certification exams. Good luck in pursuit of your Java certification! Neil Edde Publisher—Certification Sybex, Inc. 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Copyright ©2005 SYBEX Inc., 1151 Marina Village Parkway, Alameda, CA 94501. www.sybex.com COPYING PROHIBITED © Contents at a Glance Introduction xvii Assessment Test xxiii Chapter 1 Language Fundamentals 3 Chapter 2 Operators and Assignments 37 Chapter 3 Modifiers 71 Chapter 4 Converting and Casting 101 Chapter 5 Flow Control, Assertions, and Exception Handling 129 Chapter 6 Objects and Classes 167 Chapter 7 Threads 213 Chapter 8 The java.lang and java.util Packages 249 Chapter 9 I/O and Streams 311 Chapter 10 About the Developer’s Exam 349 Chapter 11 Swing Components 357 Chapter 12 Layout Managers 395 Chapter 13 Object Streams and RMI 435 Chapter 14 Putting It All Together 461 Appendix A Practice Exam 475 Glossary 499 Index 509 Copyright ©2005 SYBEX Inc., 1151 Marina Village Parkway, Alameda, CA 94501. www.sybex.com COPYING PROHIBITED © Contents Introduction xvii Assessment Test xxiii Chapter 1 Language Fundamentals 3 Source Files 4 Keywords and Identifiers 5 Primitive Data Types 7 Literals 9 String Literals 11 Arrays 11 Importing 15 Class Fundamentals 19 Class Paths 19 The main() Method 19 Variables and Initialization 20 Argument Passing: By Reference or by Value 22 Garbage Collection 24 Summary 26 Exam Essentials 27 Review Questions 29 Answers to Review Questions 34 Chapter 2 Operators and Assignments 37 Overview of the Java Operators 38 Evaluation Order 39 The Unary Operators 40 The Increment and Decrement Operators: ++ and 40 The Unary Plus and Minus Operators: + and - 41 The Bitwise Inversion Operator: ~ 41 The Boolean Complement Operator: ! 41 The Cast Operator: (type) 42 The Arithmetic Operators 43 The Multiplication and Division Operators: * and / 43 The Modulo Operator: % 45 The Addition and Subtraction Operators: + and - 46 Arithmetic Error Conditions 48 Arithmetic Promotion of Operands 49 Copyright ©2005 SYBEX Inc., 1151 Marina Village Parkway, Alameda, CA 94501. www.sybex.com COPYING PROHIBITED © [...]... Lists Sets Maps Copyright 20 05 SYBEX Inc., 1151 Marina Village Parkway, Alameda, CA 94501 xiii 195 20 0 20 1 20 3 21 0 21 3 21 4 21 4 21 7 21 7 21 9 21 9 22 0 22 0 22 2 22 2 22 3 22 4 22 5 22 7 22 9 23 4 23 4 23 6 23 8 23 9 24 0 24 1 24 6 24 9 25 1 25 3 25 4 25 4 25 8 26 0 26 2 26 8 26 9 27 1 27 2 27 5 www.sybex.com © xiv COPYING PROHIBITED Contents Support Classes Collections and Code Maintenance Generic Collections Generics and the API Pages... Questions Chapter 10 About the Developer’s Exam 27 7 27 9 28 5 28 8 28 9 29 0 29 1 29 4 3 02 3 02 304 309 311 3 12 313 313 317 321 321 323 327 330 3 32 338 338 339 345 349 Are You Ready? Formalities of the Exam The Project Assignment The Essay Exam Grading Chapter 11 350 351 3 52 353 354 Swing Components 357 A Strategy for Designing the GUI Step 1: Identify Needed Components Step 2: Isolate Regions of Behavior Step 3: Sketch... The java. lang and java. util Packages The Object Class The Math Class Strings The String Class The StringBuffer and StringBuilder Classes String Concatenation the Easy Way The Wrapper Classes The Collections Framework The Collection Superinterface and Iteration Lists Sets Maps Copyright 20 05 SYBEX Inc., 1151 Marina Village Parkway, Alameda, CA 94501 xiii 195 20 0 20 1 20 3 21 0 21 3 21 4 21 4 21 7 21 7 21 9 21 9... Invocation Remote References RMI Step by Step Summary Copyright 20 05 SYBEX Inc., 1151 Marina Village Parkway, Alameda, CA 94501 xv 3 62 3 62 3 62 3 62 363 363 363 364 367 376 377 3 82 387 389 389 391 3 92 395 396 399 401 401 404 405 4 12 417 433 434 435 436 436 437 437 440 443 447 4 52 4 52 453 459 www.sybex.com © xvi COPYING PROHIBITED Contents Chapter 14 461 Javadoc Thread Issues Extra Credit RMI or Object Streams?... Specialized certifications are the best way to stand out from the crowd In this age of technology certifications, you will find hundreds of thousands of administrators who have successfully completed the Microsoft and Cisco certification tracks To set yourself apart from the crowd, you need a little bit more The Java Programmer Certification is the most basic Java certification and the Developer Certification. .. void main(String [] a) { int [] b = [1 ,2, 3,4,5,6,7,8,9,0]; System.out.println("a [2] =" + a [2] ); } } A The code compiles but does not output anything B “a [2] =3” is printed out to the console C “a [2] =2 is printed out to the console D The code does not compile E None of the above 12 What is the value of x after the following operation is performed? x = 23 % 4; A 23 B 4 C 5.3 D 3 E 5 13 Given the following... 30 = 1) Once this is completed, the final equation is executed as 32 * 1, which equals 32 See Chapter 2 for more information 21 A The StringBuilder class is compatible with StringBuffer but is not threadsafe and is generally faster See Chapter 8 for more information 22 D The sizes of the primitives are as follows: byte, 8 bits; char, 16 bits; short, 16 bits; int, 32 bits; float, 32 bits; long, 64 bits;... False 22 Select the list of primitives ordered in smallest to largest bit size representation A boolean, char, byte, double B byte, int, float, char C char, short, long, float D char, int, float, long E None of the above 23 Which class provides locale-sensitive text formatting for date and time information? A java. util.TimeFormat B java. util.DateFormat C java. text.TimeFormat D java. text.DateFormat 24 ... Conversion Object Method-Call Conversion Object Reference Casting Summary Exam Essentials Review Questions Answers to Review Questions Copyright 20 05 SYBEX Inc., 1151 Marina Village Parkway, Alameda, CA 94501 49 101 1 02 103 103 107 108 109 1 12 1 12 115 115 120 120 121 127 www.sybex.com © xii COPYING PROHIBITED Contents Chapter 5 Flow Control, Assertions, and Exception Handling The Loop Constructs The while()... COPYING PROHIBITED Introduction We believe you’ll find this book particularly helpful because it was written by Java instructors and practitioners who have also taken part in the writing of the Java certification exams Why Become Java 2 Certified? There are a number of reasons for becoming Java 2 certified: It provides proof of professional achievement It increases your marketability It provides greater . written by Java instruc- tors and practitioners who have also taken part in the writing of the Java certification exams. Why Become Java 2 Certified? There are a number of reasons for becoming Java. and in-depth knowledge of programming Java. How to Become a Sun Certified Java Programmer for the Java 2 Platform 5.0 You can take the Sun Certified Java Programmer Exam whenever you like by. Sun Certified Java Developer for the Java 2 Platform 5.0 The Sun Certified Java Developer Exam costs $250. You aren’t allowed to register for this exam unless you are a certified Java programmer.