Terminology

Introduction

This chapter presents the basic concepts of Java programming. Here you will learn how to write simple Java programs using primitive and reference data types. The objective of writing simple programs is to gain a firm understanding of the structure of Java applications while at the same time building skill and confidence in your ability to create, edit, and compile Java source files and then run the resulting class files. A thorough discussion of the three different Java type categories is presented along with numerous examples of the use of primitive and reference types.

In order to master the basics of Java programming you will have to understand the concepts of statements, expressions, and operators. These will be discussed and illustrated in detail.

I will then show you how to use reference data types in your programs by introducing you to the primitive type wrapper classes. A knowledge of how these classes operate will prove handy as you progress through the text. In the process of learning about reference data types I will show you how to use the new operator and discuss the role of the Java virtual machine garbage collector.

The concepts and skills learned in this chapter create a strong foundation upon which you will build a greater understanding of the Java platform and the Java programming language.

Also, throughout this chapter I focus the discussion of basic language features to those found in Java version 1.4.2. The Java 5 feature of autoboxing of primitive data types is postponed until later in the book.