Java All-in-One For Dummies, 4th Edition

Chapter 2

Working with Variables and Data Types

In This Chapter

Creating proper variable declarations

Discovering the difference between primitive and reference types

Looking at Java's built-in data types

Introducing strings

Getting input from the console

Getting input if you're using an older version of Java

In this chapter, you find out the basics of working with variables in Java. Variables are the key to making Java programs general purpose. The Hello, World! programs in the previous chapter, for example, are pretty specific: The only thing they say is “Hello, World!” But with a variable, you can make this type of program more general. You could vary the greeting so that sometimes it would say “Hello, World!” and at other times it would say “Greetings, Foolish Mortals.” Or you could personalize the greeting, so that it said “Hello, Bob!” or “Hello, Amanda!”

Variables are also ...