In this chapter you'll explore the heart of the Java language—classes. Classes specify the objects you use in object-oriented programming. These form the basic building blocks of any Java program, as you saw in Chapter 1. Every program in Java involves classes, since the code for a program can appear only within a class definition.
You'll be exploring the details of how a class definition is put together, how to create your own classes, and how to use classes to solve your own computing problems. And in the next chapter, you'll build on this to look at how object-oriented programming helps you work with sets of related classes.
By the end of this chapter you will have learned:
What a class is, and how you define a class
How to implement class constructors
How to define class methods
What method overloading is
What a recursive method is and how it works
How to create objects of a class type
What packages are and how you can create and use them
What access attributes are and how you should use them in your class definitions
What nested classes are and how you use them
When you should add the finalize() method to a class
What native methods are