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Java™ProgrammingLanguage
Revision D, April 2000
SL-275
StudentGuideWithInstructor Notes
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iii
Copyright 2000 Sun Microsystems, Inc. All Rights Reserved. Enterprise Services April 2000, Revision D
Contents
About This Course.....................................................................................xix
Course Goal ....................................................................................... xix
Course Overview ............................................................................... xx
Course Map........................................................................................ xxi
Module-by-Module Overview ....................................................... xxii
Course Objectives........................................................................... xxvi
Skills Gained by Module.............................................................. xxvii
Guidelines for Module Pacing ................................................... xxviii
Topics Not Covered........................................................................ xxix
How Prepared Are You?................................................................. xxx
Introductions ................................................................................... xxxi
How to Use Course Materials ...................................................... xxxii
Course Icons and Typographical Conventions ....................... xxxiv
Course Icons.......................................................................... xxxiv
Typographical Conventions .................................................xxxv
Notes to the Instructor................................................................ xxxvii
Getting Started ...........................................................................................1-1
Objectives ........................................................................................... 1-1
Relevance............................................................................................ 1-2
Additional Resources ....................................................................... 1-3
What Is the Java Technology? ......................................................... 1-4
Primary Goals of the Java Technology ..................................1-5
A Basic Java Application.................................................................. 1-8
TestGreeting.java ................................................................1-8
Greeting.java.........................................................................1-8
TestGreeting Described ........................................................1-9
Greeting Described ...............................................................1-12
Compiling and Running TestGreeting.............................1-14
Troubleshooting the Compilation ........................................1-16
Java - Behind the Scenes................................................................. 1-18
The Java Runtime Environment............................................1-18
The Java Virtual Machine ......................................................1-19
iv Java Programming Language
Copyright 2000 Sun Microsystems, Inc. All Rights Reserved. Enterprise Services April 2000, Revision D
Garbage Collection .................................................................1-22
Code Security...........................................................................1-24
Exercise: Performing Basic Tasks.................................................. 1-30
Preparation...............................................................................1-30
Tasks .........................................................................................1-30
Check Your Progress ...................................................................... 1-31
Think Beyond .................................................................................. 1-32
Object-Oriented Programming ...............................................................2-1
Objectives ........................................................................................... 2-1
Relevance............................................................................................ 2-2
What Is Object-Oriented Programming?....................................... 2-3
Analysis and Design.................................................................2-5
Analysis and Design Example ................................................2-7
Abstraction.................................................................................2-8
Classes as Blueprints for Objects ............................................2-9
Declaring Java Classes.................................................................... 2-10
Declaring Attributes ....................................................................... 2-11
Declaring Methods.......................................................................... 2-12
Accessing Object Members............................................................ 2-14
Information Hiding......................................................................... 2-15
The Problem.............................................................................2-15
The Solution.............................................................................2-16
Encapsulation .................................................................................. 2-17
Declaring Constructors .................................................................. 2-18
The Default Constructor ................................................................ 2-20
Source File Layout .......................................................................... 2-21
Software Packages .......................................................................... 2-23
The package Statement.................................................................. 2-24
The import Statement.................................................................... 2-26
Directory Layout and Packages .................................................... 2-28
Development ...........................................................................2-29
Deployment .............................................................................2-30
Terminology Recap......................................................................... 2-31
Using the Java Technology API Documentation........................ 2-32
Exercise: Using Objects and Classes............................................. 2-35
Preparation...............................................................................2-35
Tasks .........................................................................................2-35
Exercise Summary...................................................................2-36
Check Your Progress ...................................................................... 2-37
Think Beyond .................................................................................. 2-38
Identifiers, Keywords, and Types...........................................................3-1
Objectives ........................................................................................... 3-1
Relevance............................................................................................ 3-2
Comments .......................................................................................... 3-3
Semicolons, Blocks, and Whitespace.............................................. 3-4
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Copyright 2000 Sun Microsystems, Inc. All Rights Reserved. Enterprise Services April 2000, Revision D
Identifiers ........................................................................................... 3-7
Java Keywords................................................................................... 3-9
Basic Java Types .............................................................................. 3-10
Primitive Types .......................................................................3-10
Logical – boolean ...................................................................3-11
Textual – char and String ...................................................3-12
Integral – byte, short, int, and long.................................3-14
Floating Point – float and double......................................3-17
Variables, Declarations, and Assignments.................................. 3-19
Java Reference Types...................................................................... 3-20
Constructing and Initializing Objects .......................................... 3-21
Memory Allocation and Layout............................................3-22
Explicit Attribute Initialization .............................................3-23
Executing the Constructor .....................................................3-24
Variable Assignment ..............................................................3-25
This Is Not the Whole Story ..................................................3-26
Assignment of Reference Types.................................................... 3-27
Pass-by-Value .................................................................................. 3-29
The this Reference......................................................................... 3-32
Java Coding Conventions .............................................................. 3-35
Exercise: Using Objects .................................................................. 3-38
Preparation...............................................................................3-38
Tasks .........................................................................................3-38
Exercise Summary...................................................................3-39
Check Your Progress ...................................................................... 3-40
Think Beyond .................................................................................. 3-41
Expressions and Flow Control.................................................................4-1
Objectives ........................................................................................... 4-1
Relevance............................................................................................ 4-2
Expressions ........................................................................................ 4-3
Variables and Scope..................................................................4-3
Variable Scope Example...........................................................4-5
Variable Initialization...............................................................4-6
Operators....................................................................................4-7
Logical Operators......................................................................4-8
Short-Circuit Logical Operators..............................................4-9
Bitwise Logical Operators......................................................4-10
Right-Shift Operators >> and >>>........................................4-11
Left-Shift Operator (<<) .........................................................4-13
Shift Operator Examples........................................................4-14
String Concatenation With +.................................................4-15
Casting......................................................................................4-16
Promotion and Casting of Expressions................................4-18
