SCJA Sun Certified Java Associate Study Guide (Exam CX-310-019) (Certification Press)

405 Pages·2009·2.94 MB·English

by  Robert Liguori

SCJA Sun® Certified Java™
Associate Study Guide
(Exam CX-310-019)
Robert Liguori
Edward Finegan
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About the Authors
Robert Liguori is a Senior Software Engineer and has been developing, maintaining,
and testing air traffic management systems since 1996. He is currently architecting,
designing, developing, and maintaining Java EE E-business systems and Java-based
air traffic management systems. Mr. Liguori is a Senior Software Engineer with
MetaTec Group, Inc.
Mr. Liguori has a bachelor’s degree in computer science and information technology
from Richard Stockton College of New Jersey. He is the founder and president of
the Atlantic City Java User Group (ACJUG) supporting the southern New Jersey
area (http://acjug.dev.java.net). He is a Sun Certified Java Associate (SCJA) and
Sun Certified Java Programmer (SCJP) and is currently pursuing various other Sun
certifications.
For the better part of 2007, Mr. Liguori spent his free time with his wife co-authoring
a handy Java reference guide: Java Pocket Guide, by Robert and Patricia Liguori
(O’Reilly Media Inc., 2008). It succeeded in capturing Java’s fundamentals in a
companion-size book.
Mr. Liguori enjoys spending time with his family, as well as surf fishing for striped
bass and red drum along the East Coast of the United States.
He can be contacted at [email protected].
Edward Finegan is a Senior Java Software Developer and is currently working in
the casino gaming industry where he designs and implements software for gaming
machines. He has previous experience in air traffic management systems and radar
protocols.
Mr. Finegan has a bachelor’s degree in computer science from Rowan University,
and a master’s degree in computer science from Virginia Commonwealth University.
His thesis was entitled Intelligent Autonomous Data Categorization, which examined the
possibility of using machine-learning algorithms to intelligently and autonomously
categorize data. He is also a Sun Certified Java Professional.
Mr. Finegan is an avid Philadelphia sports fan. He enjoys outdoor activities and
home-improvement projects, as well as tinkering with the latest technologies.
He can be contacted at [email protected].
About the technical editor
Alistair Grieve started his career as a Tandem NonStop COBOL programmer. Since
then, he has worked for more than 20 years as a software developer and database
administrator, primarily in the financial services sector, in the UK, the U.S.A., and
New Zealand. He is also a freelance technical editor.
Mr. Grieve is an engineering science graduate of the University of Oxford. He is a
Sun Certified Java Programmer (SCJP) and Web Component Developer (SCWCD),
as well as an Oracle Certified Professional (OCP) database administrator.
He can be contacted at [email protected].
About LearnKey
LearnKey provides self-paced learning content and multimedia delivery solutions
to enhance personal skills and business productivity. LearnKey claims the largest
library of rich streaming-media training content that engages learners in dynamic
media-rich instruction, complete with video clips, audio, full motion graphics, and
animated illustrations. LearnKey can be found on the Web at www.LearnKey.com.
To Dad, Mom, Michael, Patti Ann, Ashleigh, Joseph, Kara and Tristan
—Robert J. Liguori
To my soon-to-be-wife Shannon for having ample patience during this
endeavor and to my Mom and Dad for their ongoing support.
—Edward G. Finegan
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Contents At A GLAnCe
Part I
Fundamental Java Elements
1 Packaging, Compiling, and Interpreting Java Code . . . . . . . . . . . . . . 3
2 Programming with Java Statements . . . . . . . . . . . . . . . . . . . . . . . . . 41
3 Programming with Java Operators and Strings . . . . . . . . . . . . . . . . . 81
Part II
Object-Oriented Basic Concepts
4 Working with Basic Classes and Variables . . . . . . . . . . . . . . . . . . . . 129
5 Understanding Variable Scope and Class Construction . . . . . . . . . . . 161
6 Working with Classes and Their Relationships . . . . . . . . . . . . . . . . . 187
7 Understanding Class Inheritance . . . . . . . . . . . . . . . . . . . . . . . . . . . 215
8 Understanding Polymorphism . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 259
9 Representing Object-Oriented Concepts with UML . . . . . . . . . . . . . 289
Part III
Java-Related Platforms and Technologies
10 Understanding Java-Related Platforms
and Integration Technologies . . . . . . . . . . . . . . . . . . . . . . . . . . . . 323
11 Understanding Client-Side Technologies . . . . . . . . . . . . . . . . . . . . . 359
12 Understanding Server-Side Technologies . . . . . . . . . . . . . . . . . . . . . 387
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viii SCJA Sun Certified Java Associate Study Guide
Part IV
Appendixes
A About the CD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 419
B Exam-Related Packages and Classes . . . . . . . . . . . . . . . . . . . . . . . . . 425
C Unicode Standard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 429
D Bracket Conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 433
Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 435
Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 449
Contents
Acknowledgments ................................................. xvii
Preface ......................................................................... xix
Introduction ................................................................... xxv
Part I
Fundamental Java elements
1 Packaging, Compiling, and Interpreting Java Code .... 3
Understanding Packages .................................................... 4
Package Design ..................................................... 5
package and import Statements .............................. 6
exercise 1-1: Replacing Implicit import Statements
with Explicit import Statements ............................ 9
Understanding Package-Derived Classes .................................. 11
Java Utilities API .................................................. 12
Java Basic Input/Output API ..................................... 14
The Java Networking API ........................................ 14
Java Abstract Window Toolkit API .............................. 15
Java Swing API .................................................... 15
exercise 1-2: Understanding Extended Functionality
of the Java Utilities API ....................................... 17
Compiling and Interpreting Java Code .................................... 19
Java Compiler ...................................................... 19
Java Interpreter ..................................................... 22
exercise 1-3: Compiling and Interpreting
Packaged Software .............................................. 26
3
Two-Minute Drill .................................................. 29
Q&A Self Test ............................................................. 31
Self Test Answers .................................................. 34
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x SCJA Sun Certified Java Associate Study Guide
2 Programming with Java statements ..................... 41
Understanding Fundamental Statements .................................. 43
Assignment Statements ........................................... 44
Conditional Statements ........................................... 46
Iteration Statements ............................................... 54
exercise 2-1: Iterating Through an ArrayList
While Applying Conditions ................................... 58
exercise 2-2: Performing Code Refactoring .................. 60
Implementing Statement-Related Algorithms from Pseudo-code ...... 61
Pseudo-code Algorithms .......................................... 62
exercise 2-3: Knowing Your Statement-Related
Keywords ........................................................ 63
Pseudo-code Algorithms and Java ................................ 65
exercise 2-4: Implementing Pseudo-code Algorithm #1 .... 66
exercise 2-5: Implementing Pseudo-code Algorithm #2 .... 66
exercise 2-6: Implementing Pseudo-code Algorithm #3 .... 67
3
Two-Minute Drill .................................................. 68
Q&A Self Test ............................................................. 70
Self Test Answers .................................................. 74
3 Programming with Java operators and strings ........ 81
Understanding Fundamental Operators ................................... 82
Assignment Operators ............................................. 84
exercise 3-1: Using Compound Assignment Operators ..... 85
Arithmetic Operators .............................................. 87
Relational Operators ............................................... 89
Logical Operators .................................................. 92
Developing with String Objects and Their Methods ..................... 95
Strings ............................................................... 95
The String Concatenation Operator ............................. 97
exercise 3-2: Uncovering Bugs that Your
Compiler May Not Find ....................................... 100
Methods of the String Class .................................... 101
3
Two-Minute Drill .................................................. 109
Q&A Self Test ............................................................. 112
Self Test Answers .................................................. 118