Chapter 9.5, Problem 26SCP

Explanation of Solution

“Shape” interface:

An interface “Shape” that declares the common methods of shape classes is as follows,

//Create an interface for all shape classes

public interface Shape

{

    //Declare a method "getArea()"

    public double getArea();   

    //Declare a method "getPerimeter()"

    public double getPerimeter();

    //Declare a method "getSideCount()"

    public int getSideCount();

}

Explanation about the interface:

• An interface “Shape” is created to declare the common methods of all shape classes.
• The method bodies can be written only in the sub class that implements that “Shape” interface...