Java^TM 2 For Dummies^®, 2nd Edition

by Barry Burd (Drew University, Madison, NJ)

• ISBN13: 9780764568589
• ISBN10: 0764568582
• Edition: 2nd
• Format: Paperback w/CD
• Copyright: 2004-08-01
• Publisher: For Dummies

Summary

This updated bestseller covers programming essentials for the newest version of Java, the popular platform-independent, object-oriented programming languageThe material is fully updated and focuses on the new Java SDK 1.5, addressing the needs of new or inexperienced Java developersThe fun and easy writing style walks readers through Java syntax basics and helps them write their first programShows readers how to create basic Java objects and figure out when they can reuse existing codeThe new edition is also modified to better address the readers who may have some programming knowledge, but who are new to Java

Author Biography

Barry Burd is the author of Java 2 For Dummies, Beginning Programming with Java For Dummies, and Java & XML For Dummies, and a computer science professor at Drew University.

Table of Contents

Introduction	1	(1)
How to Use This Book	1	(1)
Conventions Used in This Book	1	(1)
What You Don't Have to Read	2	(1)
Foolish Assumptions	3	(1)
How This Book Is Organized	4	(2)
Part I: Getting Started	4	(1)
Part II: Writing Your Own Java Programs	4	(1)
Part III: Working with the Big Picture: Object-Oriented Programming	4	(1)
Part IV: Savvy Java Techniques	5	(1)
Part V: The Part of Tens	5	(1)
Part VI: Appendixes	5	(1)
Bonus Chapters on the CD-ROM!	5	(1)
Icons Used in This Book	6	(1)
Where to Go from Here	7	(2)
Part I: Getting Started	9	(60)
All about Java	11	(12)
What You Can Do with Java	12	(1)
Why You Should Use Java	13	(1)
Getting Perspective: Where Java Fits In	14	(1)
Object-Oriented Programming (OOP)	15	(7)
Object-oriented languages	16	(1)
Objects and their classes	17	(1)
What's so good about an object-oriented language?	18	(2)
Refining your understanding of classes and objects	20	(2)
What's Next?	22	(1)
Running Canned Java Programs	23	(20)
Downloading and Installing the Java Software Development Kit (SDK)	23	(7)
Downloading Java	25	(2)
Installing Java on your computer	27	(3)
Preparing to Use an Integrated Development Environment	30	(4)
JCreator	31	(1)
Running JCreator for the first time	31	(3)
Running Java Programs	34	(9)
Running a text-based program	34	(4)
Running a GUI on its own	38	(1)
Running a GUI on a Web page (a Java applet)	39	(4)
Using the Basic Building Blocks	43	(26)
Speaking the Java Language	43	(5)
The grammar and the common names	44	(1)
The words in a Java program	45	(3)
Checking Out Java Code for the First Time	48	(1)
Understanding the Simple Java Program	49	(9)
The Java class	49	(1)
The Java method	50	(2)
The main method in a program	52	(1)
How you finally tell the computer to do something	53	(2)
Curly braces	55	(3)
And Now, a Few Comments	58	(6)
Adding comments to your code	58	(3)
What's Barry's excuse?	61	(1)
Finding javadoc pages	61	(1)
Using comments to experiment with your code	62	(2)
Typing Your Own Code	64	(5)
Part II: Writing Your Own Java Programs	69	(70)
Making the Most of Variables and Their Values	71	(28)
Varying a Variable	71	(2)
Assignment Statements	73	(1)
Understanding the Types of Values That Variables May Have	74	(3)
An Import Declaration	77	(1)
Displaying Text	78	(1)
Numbers without Decimal Points	78	(2)
Combining Declarations and Initializing Variables	80	(1)
The Atoms: Java's Primitive Types	81	(4)
The char type	82	(2)
The boolean type	84	(1)
The Molecules and Compounds: Reference Types	85	(4)
Creating New Values by Applying Operators	89	(10)
Initialize once, assign often	92	(1)
The increment and decrement operators	92	(4)
Assignment operators	96	(3)
Controlling Program Flow with Decision-Making Statements	99	(22)
Making Decisions (Java if Statements)	100	(7)
Guess the number	100	(1)
She controlled keystrokes from the keyboard	101	(1)
Creating randomness	102	(1)
The if statement	103	(1)
The double equal sign	104	(1)
Brace yourself	105	(1)
Indenting if statements in your code	105	(1)
Elseless in Ifrica	106	(1)
Forming Conditions with Comparisons and Logical Operators	107	(6)
Comparing numbers; comparing characters	107	(1)
Comparing objects	108	(3)
Importing everything in one fell swoop	111	(1)
Java's logical operators	111	(2)
Building a Nest	113	(2)
Choosing among Many Alternatives (Java switch Statements)	115	(6)
Your basic switch statement	116	(3)
To break or not to break	119	(2)
Controlling Program Flow with Loops	121	(18)
Repeating Instructions Over and Over Again (Java while Statements)	122	(3)
Repeating a Certain Number of Times (Java for Statements)	125	(4)
The anatomy of a for statement	126	(2)
The world premiere of ``Al's All Wet''	128	(1)
Repeating Until You Get What You Want (Java do Statements)	129	(5)
Reading a single character	132	(1)
File handling in Java	133	(1)
Variable declarations and blocks	133	(1)
Loops Made Painless	134	(5)
Don't need no stinking counters	134	(2)
Grouping things together	136	(1)
Anatomy of an enhanced for loop	137	(2)
Part III: Working With the Big Picture: Object-Oriented Programming	139	(80)
Thinking in Terms of Classes and Objects	141	(28)
Defining a Class (What It Means to Be an Account)	142	(5)
Declaring variables and creating objects	144	(2)
Initializing a variable	146	(1)
Using variables	146	(1)
Compiling and Running More Than One Class	147	(1)
Defining a Method within a Class (Displaying an Account)	148	(4)
An account that displays itself	150	(1)
The display method's header	151	(1)
Sending Values to and from Methods (Calculating Interest)	152	(10)
Passing a value to a method	155	(1)
Returning a value from the getInterest method	156	(2)
Making numbers look good	158	(4)
Hiding Details with Accessor Methods (Why You Shouldn't Micromanage a Bank Teller)	162	(7)
Good programming	162	(3)
Public lives and private dreams: Making a variable name inaccessible	165	(2)
Enforcing rules with accessor methods	167	(2)
Saving Time and Money: Reusing Existing Code	169	(30)
Defining a Class (What It Means to Be an Employee)	170	(4)
The last word on employees	170	(2)
Putting your class to good use	172	(1)
Cutting a check	173	(1)
Working with Disk Files (A Brief Detour)	174	(9)
Storing data in a file	175	(2)
Copying and pasting code	177	(1)
Reading from a file	178	(2)
Who moved my file?	180	(1)
Adding directory names to your filenames	181	(1)
Reading a line at a time	182	(1)
Defining Subclasses (What It Means to Be a Full-Time Employee or a Part-Time Employee)	183	(6)
Creating a subclass	185	(3)
Creating subclasses is habit-forming	188	(1)
Using Subclasses	189	(6)
A program for the minimalist	189	(3)
A program for the maximalist	192	(3)
Overriding Existing Methods (Changing the Payments for Some of Your Employees)	195	(4)
Constructing New Objects	199	(20)
Defining Constructors (What It Means to Be a Temperature)	200	(8)
What is a temperature?	200	(2)
What you can do with a temperature	202	(1)
Calling new Temperature (32.0): A case study	203	(3)
enum types as first-class citizens	206	(1)
Some things never change	207	(1)
More Subclasses (Doing Something about the Weather)	208	(7)
Building better temperatures	208	(2)
Constructors for subclasses	210	(1)
Using all this stuff	211	(1)
The default constructor	212	(2)
An invisible constructor call	214	(1)
A Constructor That Does More	215	(4)
Part IV: Savvy Java Techniques	219	(86)
Putting Variables and Methods Where They Belong	221	(28)
Defining a Class (What It Means to Be a Baseball Player)	222	(6)
Another way to beautify your numbers	223	(1)
Using the Player class	223	(2)
Nine, count'em, nine	225	(1)
Don't get all GUI on me	226	(1)
Tossing an exception from method to method	227	(1)
Making Static (Finding the Team Average)	228	(7)
Why is there so much static?	230	(1)
Displaying the overall team average	231	(2)
Static is old hat	233	(1)
Could cause static; handle with care	234	(1)
Experiments with Variables	235	(6)
Putting a variable in its place	236	(2)
Telling a variable where to go	238	(3)
Passing Parameters	241	(8)
Pass by value	241	(2)
Returning a result	243	(1)
Pass by reference	244	(2)
Returning an object from a method	246	(1)
Epilogue	247	(2)
Using Arrays and Collections to Juggle Values	249	(30)
Getting Your Ducks All in a Row	249	(12)
Creating an array in two easy steps	251	(1)
Storing values	252	(3)
Tab stops and other special things	255	(1)
Using an array initializer	255	(1)
Stepping through an array with the enhanced for loop	256	(1)
Searching	257	(4)
Arrays of Objects	261	(6)
Using the Room class	262	(3)
Yet another way to beautify your numbers	265	(1)
The conditional operator	266	(1)
Command Line Arguments	267	(6)
Using command line arguments in a Java program	267	(2)
Checking for the right number of command line arguments	269	(1)
Setting up JCreator for command line arguments	270	(3)
Using Java Collections	273	(6)
Collection classes to the rescue	274	(1)
Using an Array List	275	(2)
Using generics (hot stuff!)	277	(1)
Testing for the presence of more data	277	(2)
Looking Good When Things Take Unexpected Turns	279	(26)
Handling Exceptions	280	(16)
The parameter in a catch clause	284	(1)
Exception types	285	(1)
Who's going to catch the exception?	286	(7)
Throwing caution to the wind	293	(1)
Doing useful things	294	(1)
Our friends, the good exceptions	295	(1)
Handle an Exception or Pass the Buck	296	(5)
Finishing the Job with a finally Clause	301	(4)
Part V: The Part of Tens	305	(14)
Ten Ways to Avoid Mistakes	307	(6)
Putting Capital Letters Where They Belong	307	(1)
Breaking Out of a switch Statement	308	(1)
Comparing Values with a Double Equal Sign	308	(1)
Adding Components to a GUI	308	(1)
Adding Listeners to Handle Events	309	(1)
Defining the Required Constructors	309	(1)
Fixing Non-Static References	309	(1)
Staying within Bounds in an Array	310	(1)
Anticipating Null Pointers	310	(1)
Helping Java Find its Files	311	(2)
Ten Sets of Web Resources for Java	313	(6)
The Horse's Mouth	313	(1)
Finding News, Reviews, and Sample Code	314	(1)
Improving Your Code with Tutorials	314	(1)
Finding Help on Newsgroups	314	(1)
Checking the FAQs for Useful Info	315	(1)
Opinions and Advocacy	315	(1)
Looking for Java Jobs	315	(1)
Becoming Certified in Java	316	(1)
Developing Servlets	316	(1)
Everyone's Favorite Sites	316	(3)
Part VI: Appendixes	319	(2)
Appendix A: Using the CD-ROM	321	(10)
What You Can Expect to Find on the CD-ROM	321	(1)
System Requirements	322	(1)
Using the CD with Microsoft Windows	323	(1)
Using the CD with Mac OS	324	(1)
Running the Java Code That's in This Book	325	(1)
Freeware, Shareware, and Just Plain Ware	326	(2)
JCreator	326	(1)
Adobe Acrobat Reader	327	(1)
Jindent	327	(1)
NetCaptor	328	(1)
WinOne	328	(1)
And, If You Run into Any Trouble	328	(3)
Appendix B: When to Use Words Like ``public'' and ``private''	331	(10)
Members versus Classes	331	(1)
Access Modifiers for Members	332	(6)
Default access	334	(1)
Protected access	334	(4)
Access Modifiers for Classes	338	(3)
Index	341	(20)
End-User License Agreement	361