End of Chapter

You may wish to review the following. Click on a subject that interests you to go to where it was discussed.

• abstract class Abstract class.
• abstract method Abstract method.
• abstract class, when required When a class must be declared to be abstract.
• abstract class, advantage Advantage of using an abstract class.
• abstract class, instantiation Can't instantiate an abstract class.
• parent class, using a variable in Using a variable of a parent type.
• polymorphism Polymorphism
• descendant rule What types of objects a variable can refer to.

The next chapter will discuss more about polymorphism.