Jim Keogh - Java Demystified

JIM KEOGH

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ISBN: 978-0-07-146997-5
MHID: 0-07-146997-4

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This book is dedicated to Anne, Sandy, Joanne,
Amber-Leigh Christine, and Graaf, without whose
help and support this book couldn't be written.

Jim Keogh is a member of the faculty of Columbia University where he teaches courses on Java Application Development, and is also a member of the Java Community Process Program. He developed the first e-commerce track at Columbia and became its first chairperson. Jim spent more than a decade developing advanced systems for major Wall Street firms and is also the author of several best-selling computer books.

This book is for everyone who wants to learn the basics of the Java programming language without taking a formal course. This book also serves as a supplemental classroom text. For best results, you should start at the beginning of the book and go straight through.

If you are confident about your basic knowledge of programming, skip the first chapter but take the quiz at the end of the chapter to see if you are actually ready to jump into Java.

If you get 90 percent of the answers correct, you're ready. If you get 75 to 89 percent correct, skim through Chapters 1 and 2. If you get less than 75 percent of the answers correct, then find a quiet place and begin reading . Doing so will get you in shape to tackle the rest of the chapters on Java.

In order to learn Java, you must have some computer skills. If we were to tell you otherwise, we'd be cheating you. Don't be intimidated. None of the computer knowledge you need goes beyond basic use of the operating system and how to enter text into an editor.

This book includes a practice quiz at the end of every chapter. These quizzes contain questions that are similar to the kinds of questions used in a Java course. You can and should refer to the chapters when taking the quizzes. When you think you're ready, take a quiz, write down your answers, and then give your list of answers to a friend. Have your friend tell you your score, but not which questions you answered incorrectly. You'll find the answers in the back of the book. Stay with one chapter until you pass the quiz.

There is also a final exam at the end of this book. The questions are practical and are drawn from all chapters in the book. Take the exam when you have finished all the chapters and have completed all the quizzes. A satisfactory score is at least 75 percent correct answers. Have a friend tell you your score without letting you know which questions you missed on the exam.

We recommend that you spend an hour or two each day with the book. You should expect to complete one chapter each week. Take it at a steady pace. Take time to absorb the material. Don't rush. You'll complete the course in a few months, and then you can use this book as a comprehensive permanent reference.

Computer programming might seem mystifying and something that should be left to university scientists, but it isn't. With a little time and effort you can easily master computer programming and take control over your computer in a way you never thought you could. If you can read this book and take a few notes, you have all the skills needed to write a computer program. A computer program is a set of instructions for the computer to follow. Those instructions are written in a programming language that is very similar to English. There are many computer languages. One of the more popular is Java. By now you probably have heard all the hoopla about Java and how Java is revolutionizing the world of computer programming. You'll be in the forefront of this revolution by learning how to put your computer through its paces by writing your own Java program. Let's begin at the beginning with the basics and then work up to everything you need to know to write a Java program.

You probably use a personal computer; however, a personal computer is only one kind of computer. Other kinds of computers include personal digital assistants (PDAs), powerful computers that run corporations, and tiny computers in automobiles, aircraft, and home appliances.