Cay S. Horstmann - Core Java Volume I--Fundamentals

Core Java

Volume IFundamentals

Ninth Edition

Cay S. Horstmann
Gary Cornell

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ISBN-13: 978-0-13-708189-9
ISBN-10: 0-13-708189-8

Text printed in the United States on recycled paper at Edwards Brothers Malloy in Ann Arbor, Michigan.

First printing, November 2012

Contents

Preface

To the Reader

In late 1995, the Java programming language burst onto the Internet scene and gained instant celebrity status. The promise of Java technology was that it would become the universal glue that connects users with information wherever it comes fromweb servers, databases, information providers, or any other imaginable source. Indeed, Java is in a unique position to fulfill this promise. It is an extremely solidly engineered language that has gained acceptance by all major vendors, except for Microsoft. Its built-in security and safety features are reassuring both to programmers and to the users of Java programs. Java even has built-in support for advanced programming tasks, such as network programming, database connectivity, and multithreading.

Since 1995, eight major revisions of the Java Development Kit have been released. Over the course of the last 17 years, the Application Programming Interface (API) has grown from about 200 to over 3,000 classes. The API now spans such diverse areas as user interface construction, database management, internationalization, security, and XML processing.

The book you have in your hands is the first volume of the ninth edition of Core Java . Each edition closely followed a release of the Java Development Kit, and each time, we rewrote the book to take advantage of the newest Java features. This edition has been updated to reflect the features of Java Standard Edition (SE) 7.

As with the previous editions of this book, we still target serious programmers who want to put Java to work on real projects . We think of you, our reader, as a programmer with a solid background in a programming language other than Java, and we assume that you dont like books filled with toy examples (such as toasters, zoo animals, or nervous text). You wont find any of these in our book. Our goal is to enable you to fully understand the Java language and library, not to give you an illusion of understanding.

In this book you will find lots of sample code demonstrating almost every language and library feature that we discuss. We keep the sample programs purposefully simple to focus on the major points, but, for the most part, they arent fake and they dont cut corners. They should make good starting points for your own code.

We assume you are willing, even eager, to learn about all the advanced features that Java puts at your disposal. For example, we give you a detailed treatment of

With the explosive growth of the Java class library, a one-volume treatment of all the features of Java that serious programmers need to know is no longer possible. Hence, we decided to break up the book into two volumes. The first volume, which you hold in your hands, concentrates on the fundamental concepts of the Java language, along with the basics of user-interface programming. The second volume, Core Java, Volume IIAdvanced Features (forthcoming, ISBN: 978-0-13-708160-8), goes further into the enterprise features and advanced user-interface programming. It includes detailed discussions of

When writing a book, errors and inaccuracies are inevitable. Wed very much like to know about them. But, of course, wed prefer to learn about each of them only once. We have put up a list of frequently asked questions, bugs fixes, and workarounds on a web page at http://horstmann.com/corejava. Strategically placed at the end of the errata page (to encourage you to read through it first) is a form you can use to report bugs and suggest improvements. Please dont be disappointed if we dont answer every query or dont get back to you immediately. We do read all e-mail and appreciate your input to make future editions of this book clearer and more informative.

A Tour of This Book

gives an overview of the capabilities of Java that set it apart from other programming languages. We explain what the designers of the language set out to do and to what extent they succeeded. Then, we give a short history of how Java came into being and how it has evolved.

In , we tell you how to download and install the JDK and the program examples for this book. Then we guide you through compiling and running three typical Java programsa console application, a graphical application, and an appletusing the plain JDK, a Java-enabled text editor, and a Java IDE.

starts the discussion of the Java language. In this chapter, we cover the basics: variables, loops, and simple functions. If you are a C or C++ programmer, this is smooth sailing because the syntax for these language features is essentially the same as in C. If you come from a non-C background such as Visual Basic, you will want to read this chapter carefully.

Object-oriented programming (OOP) is now in the mainstream of programming practice, and Java is an object-oriented programming language. introduces encapsulation, the first of two fundamental building blocks of object orientation, and the Java language mechanism to implement itthat is, classes and methods. In addition to the rules of the Java language, we also give advice on sound OOP design. Finally, we cover the marvelous javadoc tool that formats your code comments as a set of hyperlinked web pages. If you are familiar with C++, you can browse through this chapter quickly. Programmers coming from a non-object-oriented background should expect to spend some time mastering the OOP concepts before going further with Java.