3. More on Object-Oriented Programming
This chapter is a continuation of the previous
chapter on object-oriented programming. Here you will learn about
- class hierarchy and inheritance;
- the way classes can be organized in Java.
This exposition will still be at basic level: access control and modification
of classes will be treated in the programming
language chapter.
The main example used to explain object-oriented
programming at practical level is an extension of drawing letters
on the computer screen: we shall add more variation such as upper and
lower case letters, digits, and blinking objects.