Chapter 8, Problem 5E

 Implementation of the derived class “Square”:

The implementation of the derived class “Square” is given below:

Create a derived class “Square” which is extends from the “DrawableShape”.

• • Declare the “length” variable.
• • Define the constructor.
  • ○ Call the “super” method.
  • ○ Set the values to the declared variables.
• • The “getLength” method is used to return the “length”.
• • The “setLength” method is used to set the length.
• • The “getArea” method is used to return the area of the square.
• • The “getPerimeter” method is used to return the perimeter of the square.
• • Define the “draw” method.
  • ○ Declare the variables and calculate the “xLeft” and “yTop” values.
  • ○ Display the square in center position.
  • ○ The “*” character is used to display the square.
  • ○ Display the characters are taller in vertical position when compare to horizontal position.
• • Definition of main method.
  • ○ Create an object for the class “Square”.
  • ○ Call the method “draw”.
  • ○ Call and display the length, area, perimeter and color of the square.

The implementation of the base class “DrawableShape” is given below:

• • Declare the “x”, “y”, and “color” variables.
• • Define the constructor.
  • ○ Set the values to the declared variables.
• • The “getX” method is used to return the “x”.
• • The “getY” method is used to return the “y”.
• • The “getColor” method is used to return the “color”.
• • The “move” method is used to calculate the “x” and “y” locations.
• • The “draw” method will need to be defined in concrete subclasses.

 Program:

 Filename: “Square.java”

//definition of "Square" class

public class Square extends DrawableShape

{

    //declare the integer variable

    private int length;

    //definition of constructor

    public Square(int x, int y, int len, String c)

    {

        //call the method

        super(x, y, c);

        //set the value

        length = len;

    }

    //definition of "getLength" method

    public int getLength()

    {

        //return the length

        return length;

    }

    //definition of "setLength" method

    public void setLength(int len)

    {

        //set the value

        length = len;

    }

    //definition of "getArea" method

    public int getArea()

    {

        //return the area

        return length * length;

    }

    //definition of "getPerimeter" method

    public int getPerimeter()

    {

        //return the perimeter

        return 2 * length;

    }

    //definition of "draw" method

    public void draw()

    {

/*declare and calculate the value to the variable*/

        int xLeft = getX() - length/2;

        int yTop = getY() - length/2;

        // check the condition

        for(int i=1; i<yTop; i++)

        {

            //display the new line

            System.out.println();

        }

        // declare and set the null value

        String offset = "";

        // check the condition

        for(int j=1; j<xLeft; j++)

        {

            //set the value

            offset = offset + " ";

        }

        // declare and set the offset value

        String top = offset;

        // check the condition

        for(int j=0; j<length; j++)

        {

            //set the value

            top = top + "*";

        }

        //display the top line

        System...