Java Essentials For Dummies

Chapter 10

Making Your Own Classes

IN THIS CHAPTER

Creating your own class

Looking at the pieces of a class declaration

Finding out about class fields

Constructing constructors

Okay, class, it’s time to learn how to create your own classes.

In this chapter, you discover the basics of creating classes in Java. All Java programs use or consist of classes, so you’ve already seen many examples of classes. You’ve seen class headers such as public class GuessingGame and static methods such as public static void main. Now, in this chapter, we show you how to create programs that have more than one class.

Declaring a Class

All classes must be defined by a class declaration — lines of code that provide the name for the class and the body of the class. Here’s the most basic form of a class declaration:

[public] class ClassName {class-body}

The public keyword indicates that this class is available for use by other classes. Although it’s optional, you usually include it in your class declarations. After all, the main reason you write class declarations is so other classes can create objects ...