Introduction

In this introduction

This Book Is for You

How This Book Is Organized

Conventions Used in This Book

Welcome to the amazing and dynamic world of Java! If you are brand new to Java, get ready for a solid introduction to the hottest programming technology in the industry. Java is an extremely rich language that is relatively simple and easy to learn, especially when compared to some of the languages from which its inventors drew. Java gives you unprecedented support for even the most complex of tasks through its powerful API.

What is Java? Java is a revolutionary programming language that was introduced by Sun Microsystems in June 1995. Since then, hundreds of thousands of programmers have picked up books just like this one and have realized just how powerful the language is.

Java is an object-oriented programming language, which means that programmers using Java can develop complex, yet maintainable , programs more easily than programmers attempting to do the same with procedural languages. In addition, Java has built-in support for threads, networking, and a variety of other tools that allow you to focus more on the true requirements of your programs and less on the low-level infrastructure that you need.

A note about version numbers : This book supports the Java 2 Platform, which was first introduced with the release of SDK 1.2 and subsequently upgraded with Java 2 SDK, version 1.3. Both of these SDK versions are referred to as Java 2. This book specifically points out the enhancements found in the SDK 1.3 release to give you the most up-to-date understanding of the latest Java 2 Platform.

Note

Throughout this book, there are references to the SDK and sometimes the JDK. Sun Microsystems originally referred to (and registered) the platform as the Java Development Kit ”JDK. However, according to a Sun marketing representative, with the release of version 1.2 Sun switched from using JDK to the more general name of Software Development Kit ”SDK. For a complete explanation of this name change and how it affects parts of the Java platform, check out the marketing information on Sun's site at the following URL:

 http://java.sun.com/products/jdk/1.2/java2.html 

Another change in the packaging of Java by Sun has been to introduce the concept of multiple editions of the language. The editions are all based on the same core API and do not compete with each other in any way, but they allow developers to focus more easily on the technology that supports their particular needs. This book addresses the Java 2 Standard Edition (J2SE), which is the core of the language. Every Java developer makes use of the J2SE functionality, and it is definitely the starting point for learning the language. Sun also provides the Java 2 Enterprise Edition (J2EE), which supports distributed application development using technologies such as Java Server Pages (JSP) and Enterprise JavaBeans (EJB), and the Java 2 Micro Edition (J2ME), which supports the development of small, embedded programs for portable devices.