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JAVA
Programming

Fundamentals
Problem Solving Through Object
Oriented Analysis and Design

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JAVA
Programming

Fundamentals
Problem Solving Through Object
Oriented Analysis and Design

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Premchand S. Nair

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CRC Press
Taylor & Francis Group
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Boca Raton, FL 33487-2742
© 2009 by Taylor & Francis Group, LLC
CRC Press is an imprint of Taylor & Francis Group, an Informa business
No claim to original U.S. Government works
Printed in the United States of America on acid-free paper
10 9 8 7 6 5 4 3 2 1
International Standard Book Number-13: 978-1-4200-6547-3 (Softcover)
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Trademark Notice: Product or corporate names may be trademarks or registered trademarks, and are used only for
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Library of Congress Cataloging-in-Publication Data
Nair, Premchand S., 1956Java programming fundamentals : problem solving through object oriented analysis and design / by
Premchand S. Nair.
p. cm.
Includes bibliographical references and index.
ISBN-13: 978-1-4200-6547-3
ISBN-10: 1-4200-6547-5
1. Java (Computer program language) 2. Object-oriented programming (Computer science) I. Title.
QA76.73.J38N345 2008
005.1’17--dc22
Visit the Taylor & Francis Web site at

and the CRC Press Web site at


2008017335


Dedication
To five people in my life,
M.K. Krishna Pillai
Grandfather

S. Sukumaran Nair
Dad

Sarada Devi
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Mom

Suseela Nair
Wife

Meera Nair
Daughter

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Contents
Preface

xix

Acknowledgments

xxiii

Author


xxv

CHAPTER 1 Object Model of Computation

1

INTRODUCTION

1

OBJECT MODEL OF COMPUTATION

2

DATA REPRESENTATION

5

HARDWARE OVERVIEW

5

BRIEF HISTORY OF PROGRAMMING LANGUAGES AND
MODELS OF COMPUTATION

6

CREATING AND EXECUTING JAVA PROGRAM

8


Step 1. Create Java Source File

8

Step 2. Compile Source Code into Bytecode

8

Step 3. Execute Java Program

9

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INTRODUCTION TO SOFTWARE ENGINEERING

10

Analysis and Use Case Diagram

12

REVIEW

14

EXERCISES

16


ANSWERS TO SELF-CHECK

17

CHAPTER 2 Class and Java Fundamentals

19

JAVA APPLICATION PROGRAM

20

Identifier

21

vii

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viii



Contents


Reserved Word

24

Comment Lines

24

JAVA GREETINGS PROGRAM

26

Advanced Topic 2.1: Frequently Used Escape Sequences

27

Advanced Topic 2.2: Details on println Method

29

Concatenation and the length of Strings

29

Positional Value of a Character in String

30

DATA TYPES


31

Primitive Data Types

32

boolean Data Type

33

char Data Type

33

Advanced Topic 2.3: Unicode Character Specification

35

Integer Data Type

35

Advanced Topic 2.4: Various Integer Representations

36

Floating Point Data Type

36


Advanced Topic 2.5: Floating Point Notation

37

OPERATIONS ON NUMERIC DATA TYPES

37

Operator Precedence Rules

40

Rules for Evaluating Mixed Expressions

42

Advanced Topic 2.6: Mixed Expressions Involving String

44

NAMED CONSTANTS AND VARIABLES

46

Changing Data Values of Variable

51

Assignment Statement


51

INPUT STATEMENT

55

PACKAGES AND import STATEMENT

57

Single Character Input

58

INTERACTIVE MODE AND PROMPT LINES

60

EXPLICIT DATA–TYPE CONVERSION

61

Advanced Topic 2.7: Increment and Decrement Operators

63

Advanced Topic 2.8: Compound Assignment Operators

65


REVIEW

66

EXERCISES

67

PROGRAMMING EXERCISES

74

ANSWERS TO SELF-CHECK

75

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Contents

CHAPTER 3 Class Design



ix


77

CLASS

77

Attributes

78

Operations

80

METHOD INVOCATION

80

METHOD DEFINITION

82

CATEGORIES OF VARIABLES

84

Syntax Template

85


Initialization

85

Scope

85

Existence

86

return STATEMENT

86

JAVADOC CONVENTION

86

ACCESSOR METHOD

86

MUTATOR METHOD

88

toString METHOD


90

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APPLICATION-SPECIFIC METHODS

90

CONSTRUCTOR

91

PUTTING ALL PIECES TOGETHER

92

Advanced Topic 3.1: Representing Class in UML 2

94

TESTING

95

Advanced Topic 3.2: Representing Relationship in UML 2

98

Advanced Topic 3.3: Class Design, Implementation,

and Testing

99

Design

99

Decide on Attributes

100

Decide on Methods

100

Implementation

102

Testing

104

REVIEW

106

EXERCISES


108

PROGRAMMING EXERCISES

111

ANSWERS TO SELF-CHECK

112

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x



Contents

CHAPTER 4 Decision Making

115

CONTROL STRUCTURES

115

LOGICAL EXPRESSION AND OPERATORS


118

LOGICAL OPERATORS

120

RELATIONAL OPERATORS

123

RELATIONAL OPERATORS AND NUMERICAL DATA TYPES

124

RELATIONAL OPERATORS AND CHARACTER DATA TYPES

126

Advanced Topic 4.1: Relational Operators and Objects

127

LEXICOGRAPHICAL ORDERING OF STRINGS

127

Advanced Topic 4.2: Equality Operators and String Class

130


PRECEDENCE RULES

132

Advanced Topic 4.3: Syntax Error Explained

137

Advanced Topic 4.4: Short-Circuit Evaluation

137

Advanced Topic 4.5: Additional Logical Operators

138

Advanced Topic 4.6: Positive Logic

140

SELECTION STRUCTURES

142

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ONE-WAY SELECTION STRUCTURE

142


BLOCK STATEMENT

148

TWO-WAY SELECTION STRUCTURE

151

PRIMITIVE DATA TYPE boolean

156

NESTED STRUCTURES

157

Advanced Topic 4.7: Better Coding Options

161

Advanced Topic 4.8: Order of Logical Expressions

164

Advanced Topic 4.9: Overriding if ... else Pairing Rule

165

Advanced Topic 4.10: Ternary Operator


166

MULTIWAY STRUCTURE switch

167

Advanced Topic 4.11: Sharing Code in a switch Statement

170

Advanced Topic 4.12: Limitations of a switch Statement

173

Advanced Topic 4.13: Enumerated Types

177

CASE STUDY 4.1: PAYROLL FOR A SMALL BUSINESS

180

Specification

180

Input

181


Output

181

Decide on Classes

181

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Contents



xi

Decide on Attributes

181

Decide on Methods

182

Implementation


184

Application Program

193

Testing

196

REVIEW

197

EXERCISES

199

PROGRAMMING EXERCISES

204

ANSWERS TO SELF-CHECK

206

CHAPTER 5 The Power of Repetition

209


CONTROL STRUCTURES

210

USING TEXT FILE FOR INPUT

211

Declaring Exceptions

211

USING FILE FOR OUTPUT

213

Method close

213

REPETITION STRUCTURE: while

215

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Counter-ControlledApago
while Statement

218


Advanced Topic 5.1: Use of Counter inside Counter-Controlled
while Statement

222

Advanced Topic 5.2: Event-Controlled while Statement

224

Advanced Topic 5.3: Data-Controlled while Statement

227

Data Validation

227

Sentinel Data

227

REPETITION STRUCTURE: for

229

Advanced Topic 5.4: Use of Counter inside for Statement

234

Advanced Topic 5.5: Repetition Statement : do … while


235

Advanced Topic 5.6: Guidelines for Choosing Repetition Structure

238

NESTING OF CONTROL STRUCTURES

239

Advanced Topic 5.7: Statements break and continue

245

Statements break and continue with Optional Label

249

CASE STUDY 5.1: PAYROLL FOR SMALL BUSINESS: REVISITED

252

Specification

252

Input

252


Output

252

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xii



Contents

Application Program

252

Testing

256

REVIEW

256

EXERCISES


257

PROGRAMMING EXERCISES

263

ANSWERS TO SELF-CHECK

266

CHAPTER 6 Methods and Constructors

267

CLASSIFICATION OF METHODS

267

Math Class

270

Character Class

272

String Class

272


METHOD INVOCATION

274

USER-DEFINED METHODS

281

Formal Parameter List

282

Signature of a Method

282

Parameter Passing Apago PDF Enhancer

284

CONSTRUCTORS

297

Copy Constructor

305

Self-Reference


308

Advanced Topic 6.1: Common Methods

309

copy Method

309

equals Method

313

Advanced Topic 6.2: Finalizer and Garbage Collection

316

Advanced Topic 6.3: Class Variable

318

static Methods

321

Advanced Topic 6.4: Creating and Using Packages

328


Option 1

328

Option 2

329

Step 1

329

Step 2

330

Step 3

330

Step 4

331

Step 5

331

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Contents



xiii

CASE STUDY 6.1: FRACTION CALCULATOR

331

REVIEW

344

EXERCISES

345

PROGRAMMING EXERCISES

351

ANSWERS TO SELF-CHECK

353

CHAPTER 7 Object-Oriented Software Design


355

OBJECTS

355

Data-Centric View

356

Attribute

356

Operation

356

Client–Server View

357

Soft ware Design View

359

SUBCLASS

359


Inheritance

361

Creating Subclass

363

Invoking Method ofApago
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365

Accessing Private Attribute of Superclass

366

Invoking Constructor of Superclass

366

Subclass Objects as Superclass Instance

376

Polymorphic Behavior

377


Advanced Topic 7.1: instanceof Operator

381

Advanced Topic 7.2: Use of protected Attributes

381

Advanced Topic 7.3: Design Options

386

protected Operations

386

package Access

386

Modifier final

386

ABSTRACT CLASSES AND METHODS

387

Advanced Topic 7.4: Object Class


403

Advanced Topic 7.5: Composition

403

Accessor and Mutator Methods

404

Constructor

405

Application-Specific Services

406

INTERFACE

412

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xiv




Contents

CASE STUDY 7.1: PAYROLL FOR SMALL BUSINESS: REDESIGNED

412

REVIEW

427

EXERCISES

429

PROGRAMMING EXERCISES

432

ANSWERS TO SELF-CHECK

433

CHAPTER 8 GUI Applications, Applets, and Graphics

435

COMMON THEME BEHIND ALL GUI APPLICATION PROGRAMS

436


CREATING APPLICATION WINDOW

437

Creating New Application Class

438

Invoking Constructor of Superclass

440

Define Size of JFrame

440

Make JFrame Visible

441

Provide Graceful Way to Exit Application

441

Get Reference of Content Pane

444

Create and Place GUI Components in Content Pane


445

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Component creation

445

Component placement

448

EVENT-DRIVEN PROGRAMMING

450

Event-Driven Model of Computation

451

Implementing Listener interface

452

Registering Listener interface

454

METRIC CONVERSION HELPER


458

Advanced Topic 8.1: Programming Options for Implementing
Event Listeners

466

Option B

467

Option C

470

Option D

471

Advanced Topic 8.2: Applets

472

Creating Applet from GUI Application

473

Advanced Topic 8.3: Applet and GUI Application


483

Advanced Topic 8.4: Graphics

490

Advanced Topic 8.5: Color

494

Advanced Topic 8.6: Font

500

Advanced Topic 8.7: Drawing Services

503

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Contents



xv

REVIEW


505

EXERCISES

506

PROGRAMMING EXERCISES

508

ANSWERS TO SELF-CHECK

510

CHAPTER 9 Simple Data Structures

513

ONE-DIMENSIONAL ARRAY

514

Declaring Array

514

Instantiating Array

515


Advanced Topic 9.1: Programming Option

518

Advanced Topic 9.2: Alternate Syntax

519

Attribute length

519

PROCESSING ONE-DIMENSIONAL ARRAYS

521

Initialize Array with Certain Specific Values

522

Enhanced for Statement

522

Initialize Array Locations with Different Values

524

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Initialize Array Using User Input

525

Output Array

525

Perform Various Numeric Computations

526

Search for Item

527

CASE STUDY 9.1: MR. GRACE’S LATEST GRADING POLICY

528

Advanced Topic 9.3: Array Index Out of Bounds Exception

535

Advanced Topic 9.4: Assignment and Relational Operators

536

Advanced Topic 9.5: Role of Inheritance


539

Advanced Topic 9.6: Passing Arrays as Parameters in Methods

543

Advanced Topic 9.7: Returning Arrays in Method Invocation

549

TWO-DIMENSIONAL ARRAY

551

Declaring and Instantiating Array

552

Advanced Topic 9.8: Alternate Syntax

554

Advanced Topic 9.9: Ragged Array

555

Advanced Topic 9.10: Processing Two-Dimensional Arrays

556


Processing Specific Row

556

Processing Entire Array Row by Row

558

Processing Specific Column

559

Processing Entire Array Column by Column

560

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xvi



Contents

Advanced Topic 9.11: Passing Arrays as Parameter in Methods


561

Advanced Topic 9.12: Returning Arrays in Method Invocation

568

Advanced Topic 9.13: Multidimensional Array

571

Vector AND ArrayList CLASSES

573

Wrapper Classes

574

Advanced Topic 9.14: Abstract Data Types

583

CASE STUDY 9.2: MR. GRACE’S GRADE SHEET

584

REVIEW

588


EXERCISES

589

PROGRAMMING EXERCISES

593

ANSWERS TO SELF-CHECK

595

CHAPTER 10 Search and Sort

597

SEARCH ALGORITHMS

600

Linear Search

600

Binary Search

605

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EFFICIENCY OF ALGORITHMS

612

Empirical Approach

612

Analysis Approach

616

Advanced Topic 10.1: Levels of Complexity

617

SORT ALGORITHMS

618

Selection Sort

618

Insertion Sort

623

Bubble Sort


627

CASE STUDY 10.1: MR. GRACE’S SORTED GRADE SHEET

634

REVIEW

641

EXERCISES

642

PROGRAMMING EXERCISES

644

ANSWERS TO SELF-CHECK

644

CHAPTER 11 Defensive Programming

647

INTRODUCTION

647


EXCEPTION AND ERROR

648

Unchecked and Checked Exceptions

648

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xvii

THROWING AND CATCHING OF EXCEPTIONS

650

Throwing Exception

652

Catching Exception

654


Advanced Topic 11.1: Design Options for catch Block

663

Advanced Topic 11.2: User-Defined Exception Class

666

Advanced Topic 11.3: Design Options for Exception Handling

668

REVIEW

668

EXERCISES

669

PROGRAMMING EXERCISES

670

ANSWERS TO SELF-CHECK

671

Appendix A: Operator Precedence


673

Appendix B: ASCII Character Set

675

Appendix C: Keywords

677

Appendix D: Coding Conventions

679

Appendix E : JDK and Documentation

681

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Appendix F: Solution to Odd-Labeled Exercises

685

Index

711

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Preface
Programming is an art. Although traditional art imitates life, programming simulates life.
Every abstract concept in programming, and to a great extent in the field of computer science, has its roots in our daily life. For example, humans and possibly all other living forms
were multiprocessing long before the term entered into computer science lingo. Therefore,
any concept in programming can in fact be illustrated through examples from our dayto-day life. Such an approach not only enables the student to assimilate and internalize
the concept presented in a programming situation but also provides a solid foundation for
the very process of programming, namely, the simulation of the real world. Unfortunately,
textbooks currently on the market do not exploit this fact through examples or meaningful discussions. Thus, for many students, an abstract concept remains abstract. This is
especially true in the case of object-oriented programming. The “wow moment” one gets
by seeing programming as a simulation of the real-world situation is never realized.
This book on Java programming teaches object-oriented design and programming principles in a completely integrated and incremental fashion. This book allows the reader to
experience the world we live in as object-oriented. From the very outset the reader will
realize that everything in this world is an object. Every concept of object-oriented design
is first illustrated through real-life analogy. Corresponding Java language constructs are
introduced in an integrated fashion to demonstrate the programming required to simulate
the real-world situation. Instead of compartmentalizing all the object-oriented concepts
into one chapter, this book takes an incremental approach.
The pedagogy of this book mirrors the classroom style the author has developed over the
years as a teacher of computer science. In particular, every programming concept is introduced through simple examples followed by short programming examples. Case studies
at the end of each chapter illustrate various design issues as well as the usefulness of many
new concepts encountered in that chapter.

Java has emerged as the primary language for soft ware development. From a soft ware
engineering perspective, object-oriented design has established itself as the industry standard. Thus, more and more teaching institutions are moving toward a CS1 course that
teaches Java programming and object-oriented design principles. A common approach
followed in many textbooks on the market is to introduce object-oriented concepts from
the very beginning and ignore many traditional programming techniques completely. The
objective of this book is to present object-oriented programming and design without compromising the training one needs on traditional programming constructs and structures.

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Preface

OUTSTANDING FEATURES
• Object first approach and unified modeling language (UML). The object-oriented
design principles and UML notation are introduced from the very beginning. Case
studies at the end of each chapter take the reader through a journey that starts at
requirement specification and ends at an object-oriented program.
• Incremental approach to topic presentation. Object-oriented concepts are introduced
in an incremental fashion. This book does not compartmentalize all object-oriented
principles into one chapter; rather, new concepts are introduced and used throughout

the book.
• In-depth treatment of topics. Concepts on object-oriented design and programming
are presented in an in-depth fashion. The reader could easily master all concepts by
working through various examples. Topics that can be skipped in an introductory
course are labeled as Advanced Topic and can be omitted.
• Numerous examples drawn from everyday life. This book contains many fully developed programming examples. In addition, each concept is illustrated through
simple examples drawn from everyday life. Examples do not depend on mastery in
mathematics.
• Notes on common pitfalls and good programming practice. Notes on common pitfalls
and good programming styles appear throughout this book.

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PEDAGOGICAL ELEMENTS
Every chapter begins with a list of objectives. This list in a way summarizes the theme of
the chapter.
This book uses examples at four different levels. First, simple examples are presented. To
follow those examples, the reader need not know anything about programming or material
covered in the book until then. Second, examples are provided to illustrate the proper and
appropriate usage. Third, examples illustrate the new concept through a simple program.
Fourth, case study examples are employed to demonstrate the need and effectiveness of the
concept in a broader problem-solving context.
Introspection, a unique pedagogical element of this book, is a thought-provoking technique that will empower the instructor with ample materials to start a discussion on the
major concepts discussed in each section. This technique will enable the student to internalize the concepts in a meaningful way.
Self-check questions are presented at the end of each subsection. It not only checks the
understanding of the subject matter presented in the subsection but also highlights the
major concepts the reader is expected to know from that point on.
The quick review presented at the end of each chapter provides a summary of the chapter. The aim of the quick review is to highlight major points explained in the chapter. Thus,
quick review works as a checklist for the student as well.


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Preface



xxi

Each chapter presents major constructs of Java language along with topics that can be
covered depending on the availability of time and the student’s level of comprehension.
Those topics are labeled as Advanced Topic for easy identification.
The case study at the end of the chapter serves two important purposes. First, it allows
the reader to see the application of the new concepts learned in a practical situation. Second,
we have used two major themes throughout the book. The same theme is used at different
levels of complexity to illustrate the application and usefulness of the new concepts.
Solved exercises at the end of each chapter provide enough challenges and further consolidate the concepts introduced in the chapter.

SUPPLEMENTS AND COMPANION WEBSITE
The companion website www.premnair.net contains many useful links, documents, and
programs. The instructor can obtain the instructor’s manual that contains solutions to all
problems presented at the end of the chapter, including the programming exercises. Both
the instructor and the students can access all programs presented in this book as well as
PowerPoint presentations of each of the chapters.

CHAPTER DEPENDENCY
Chapters in this book can be taught in the sequence presented. However, the instructor has
the liberty to tailor the course on the basis of the needs as long as the following dependency

diagram is followed:

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Chapters 1 through 6

Chapter 7

Chapter 9

Chapter 10

Chapter 8

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Acknowledgments
I am extremely thankful to the following reviewers whose valuable suggestions and corrections transformed my manuscript into this book in its present form: Dr. Mark Meysenburg
(Doane College) and Dr. Charles Riedesel (University of Nebraska–Lincoln). I have a wonderful person, Randi Cohen, as my acquisition editor at Taylor & Francis. She is one of the
most kind-hearted and efficient persons I have ever known. I am so lucky to work with
her on this project. I would like to thank Amber Donley, the project coordinator, Editorial

Project Development, for the successful and timely completion of this project.
I would like to thank my wife Dr. Suseela Nair, who patiently read the entire manuscript
several times and gave me many valuable suggestions and corrections. I am grateful to my
daughter Meera Nair for all her love. My thanks are also due to my parents, S. Sukumaran
Nair and A. Sarada Devi, and grandfather M.K. Krishna Pillai for all the wonderful things
in my life. Thanks are also due to George and Susan Koshy, who are my best friends. They
have been my cheerleaders and advisors for the past two decades.
I am so grateful to Creighton University, which has supported all my professional efforts
throughout my career. I would, in particular, like to thank Dr. Robert E. Kennedy, dean
of the College of Arts and Science, one of the most decent, honest, and fair-minded persons this great institution has ever had. It is my privilege and honor to work under his
leadership.
I welcome your comments and suggestions. Please contact me through e-mail at prem@
premnair.net.

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Premchand S. Nair

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