Chapter 7 Final Tests

1 Does a superclass have access to the members of a subclass? And can the subclass access the members of a superclass?
Example: Exercise1

2 Create a subclass of TwoDShape called Circle. Include an area( ) method that calculates the area of ​​the circle and a constructor that uses super to initialize the part referring to TwoDShape.

3 How to prevent a subclass from having access to a member of a super class?

4 Describe the purpose and application of the two versions of super shown in this chapter.

5 Given the following hierarchy:
class Alpha { ...
class Beta extends Alpha { ...
Class Gamma extends Beta { ...

In what order do the constructors of these classes complete their execution when a Gamma object is instantiated?

6 A superclass reference can reference a subclass object. Explain why this is important in the context of method overriding.

7 What is an abstract class?

8 How to prevent a method from being overridden? And that a class is inherited?

9 Explain how inheritance, method overriding, and abstract classes are used to support polymorphism.

10 Which class is a superclass of all other classes?

11 A class that contains at least one abstract method must be declared
as abstract. True or false?

12 What keyword is used to create a named constant?

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