Question

Following the example of the Circle class in Section 8.2, design a class named Rectangle to represent a rectangle.

The class contains:

■ Two double data fields named width and height that specify the width and height of the rectangle. The default values are 1 for both width and height.
■ A no-arg constructor that creates a default rectangle.
■ A constructor that creates a rectangle with the specified width and height.
■ A method named getArea() that returns the area of this rectangle. A method named getPerimeter() that returns the perimeter.

Write a test program that creates two Rectangle objects —one with width 4 and height 40 and the other with width 3.5 and height 35.9. Display the width, height, area, and perimeter of each rectangle in this order.

Answer 1

RectangleTest.java

public class RectangleTest {
   public static void main(String a[]){
       Rectangle r1 = new Rectangle(4,40);
       Rectangle r2 = new Rectangle(3.5,35.9);
       System.out.println("Rectangle 1 details:");
       System.out.println("Width: "+r1.getWidth());
       System.out.println("Height: "+r1.getHeight());
       System.out.println("Area: "+r1.getArea());
       System.out.println("Perimeter: "+r1.getPerimeter());
       System.out.println();
       System.out.println("Rectangle 2 details:");
       System.out.println("Width: "+r2.getWidth());
       System.out.println("Height: "+r2.getHeight());
       System.out.println("Area: "+r2.getArea());
       System.out.println("Perimeter: "+r2.getPerimeter());
   }
}

Rectangle.java

public class Rectangle {
   private double width ;
   private double height;
   public Rectangle(){
       width = 1;
       height = 1;
   }
   public Rectangle(double w, double h){
       width = w;
       height = h;
   }
   public double getArea(){
       return 2 * width * height;
   }
   public double getPerimeter(){
       return 2 * (width + height);
   }
   public double getWidth() {
       return width;
   }
   public void setWidth(double width) {
       this.width = width;
   }
   public double getHeight() {
       return height;
   }
   public void setHeight(double height) {
       this.height = height;
   }
  
}

Output:

Rectangle 1 details:
Width: 4.0
Height: 40.0
Area: 320.0
Perimeter: 88.0

Rectangle 2 details:
Width: 3.5
Height: 35.9
Area: 251.29999999999998
Perimeter: 78.8