Introduction to unit 6

In this unit we return to the object concepts introduced at the beginning of the module. We are now able to consider the detailed aspects of the implementation of classes with methods and variables based on the programming concepts and skills covered in the units up to this one.

In fact you have already been working with the implementation of several Java object concepts, in the process of creating applets (and some applications) for investigating and solving problems with such programming features as iteration statements and strings.

It is worth keeping in mind that with object orientation there is a stark contrast between the complexity of the theory and the simplicity of the practice. 

Object technology is a relatively new field, and therefore it is changing very rapidly. This means that different people, textbooks and Web sites use different terms for the same thing. In this module we have tried to be consistent in the use of terminology, but our use of terminology is not necessarily compatible with anyone else.