PURE Java™ 2

Some Important Common Classes

The following is a short list of classes that every Java developer needs to understand. More than one of these classes will be used in just about any commercial program.

String	Vector
Date	Properties
Object	Calendar
Class	Thread
System	Wrapper classes
Runtime	Arrays

You'll explore these classes in the following sections.

String

Just about the most common class used in Java programs, besides Object (which is always the base class of every other class, so it's used implicitly), is the String class. Unlike C, a String in Java is not merely a contiguous set of characters in memory, followed by a null terminator, \0. Instead, Java Strings are objects, with properties and behaviors. The JVM has a special place in which ...