Question

Programming Language: Java

Write a class named ColoredRectangle that extends the Rectangle class (given below). The ColoredRectangle class will have an additional private String field named Color.

The ColoredRectangle class should have four constructors: a no-arg constructor; a three-arg constructor; a two-arg constructor that accepts a Rectangle object and a color; and a copy constructor.

The ColoredRectangle class should have an Equals and toString methods.

The ColoredRectangle class should have mutators and accessors for all three fields.

public class Rectangle

public class Rectangle
{
private double length;
private double width;
public Rectangle(double len, double w)
{
length = len;
width = w;
}
public void setLength(double len)
{
length = len;
}
public void setWidth(double w)
{
width = w;
}
public double getLength()
{
return length;
}
public double getWidth()
{
return width;
}
public double getArea()
{
return length * width;
}
public String toString ()
{
return “length = “ + length + “, width = “ + width ;
}
public Boolean (Rectangle other)
{
return length == other.length && width = other.width ;
}
}

Additional Instructions: In no-arg constructor, all this constructor to do is to set length and width to zero.

Write and run the following code in the demo class.

    public static void main(String[] args)
   {
       Rectangle rect1 = new Rectangle(2.0, 1.0);
       ColoredRectangle CRect1 = new ColoredRectangle();            
       ColoredRectangle CRect2 = new ColoredRectangle(4.0, 2.0, "green");
       ColoredRectangle CRect3 = new ColoredRectangle(rect1, "green");   
       ColoredRectangle CRect4 = new ColoredRectangle(CRect3);    
       System.out.println("The plain rectangle #1: " + rect1);
       System.out.println("The colored rectangle #1: " + CRect1);
       System.out.println("The colored rectangle #2: " + CRect2);
       System.out.println("The colored rectangle #3: " + CRect3);
       System.out.println("The colored rectangle #4: " + CRect4);

        if(CRect4.equals(CRect3))
           System.out.println("Colored rectangle #4 is equal to colored rectangle #3");
       else
           System.out.println("Colored rectangle #4 is NOT equals to colored rectangle #3");

        if(CRect3.equals(CRect2))
           System.out.println("Colored rectangle #3 is equal to colored rectangle #2");
       else
           System.out.println("Colored rectangle #3 is NOT equal to colored rectangle #2");
   }

Answer 1

class Rectangle {
    private double length;
    private double width;

    public Rectangle(double len, double w) {
        length = len;
        width = w;
    }

    public void setLength(double len) {
        length = len;
    }

    public void setWidth(double w) {
        width = w;
    }

    public double getLength() {
        return length;
    }

    public double getWidth() {
        return width;
    }

    public double getArea() {
        return length * width;
    }

    public String toString() {
        return "length = " + length + ",width = " + width;
    }

    public Boolean equals(Rectangle other) {
        return length == other.length && width == other.width;
    }
}

class ColoredRectangle extends Rectangle {

    private String color;

    public ColoredRectangle() {
        this(1, 1);
    }

    public ColoredRectangle(double len, double w) {
        this(len, w, "white");
    }

    public ColoredRectangle(double len, double w, String color) {
        super(len, w);
        this.color = color;
    }

    public ColoredRectangle(Rectangle rectangle, String color) {
        super(rectangle.getLength(), rectangle.getWidth());
        this.color = color;
    }

    public ColoredRectangle(ColoredRectangle rectangle) {
        super(rectangle.getLength(), rectangle.getWidth());
        this.color = rectangle.color;
    }

    public String getColor() {
        return color;
    }

    public void setColor(String color) {
        this.color = color;
    }

    public String toString() {
        return "length = " + getLength() + ",width = " + getWidth() + ",color = " + color;
    }

    public Boolean equals(ColoredRectangle other) {
        return super.equals(other) && color.equals(other.color);
    }
}

class RectangleTest {

    public static void main(String[] args) {
        Rectangle rect1 = new Rectangle(2.0, 1.0);
        ColoredRectangle CRect1 = new ColoredRectangle();
        ColoredRectangle CRect2 = new ColoredRectangle(4.0, 2.0, "green");
        ColoredRectangle CRect3 = new ColoredRectangle(rect1, "green");
        ColoredRectangle CRect4 = new ColoredRectangle(CRect3);
        System.out.println("The plain rectangle #1: " + rect1);
        System.out.println("The colored rectangle #1: " + CRect1);
        System.out.println("The colored rectangle #2: " + CRect2);
        System.out.println("The colored rectangle #3: " + CRect3);
        System.out.println("The colored rectangle #4: " + CRect4);

        if (CRect4.equals(CRect3))
            System.out.println("Colored rectangle #4 is equal to colored rectangle #3");
        else
            System.out.println("Colored rectangle #4 is NOT equals to colored rectangle #3");

        if (CRect3.equals(CRect2))
            System.out.println("Colored rectangle #3 is equal to colored rectangle #2");
        else
            System.out.println("Colored rectangle #3 is NOT equal to colored rectangle #2");
    }
}