Description Write a Java program to compute the perimeter and the area of two di
ID: 3853913 • Letter: D
Question
Description
Write a Java program to compute the perimeter and the area of two different rectangles. The user will input the length and the width of the two rectangles and the program will display the perimeter and area of each.
Write a class Rectangle with private instance variables for length and width. Provide a public constructor for initializing length and width. Also provide public methods for computing perimeter and area. Additionally provide public accessor (get) methods for accessing length and width. (For example, provide getLength( ) and getWidth ( ) methods).
Write a class TestRectangle containing the method main. From the method main, prompt the user to input the length and the width of the first rectangle. Create an object of type Rectangle and initialize its values via the constructor with the length and the width supplied by the user. Prompt the user to input the length and the width of the second rectangle. Create an object of type Rectangle and initialize its values via the constructor with the length and the width supplied by the user for the second rectangle.
Then call the object’s methods of the first object to compute its perimeter and area. Use the object’s accessor (get) methods to retrieve length and width values.
Then call the object’s methods of the second object to compute its perimeter and area. Use the object’s accessor (get) methods to retrieve length and width values of this object.
Then display values of length, width, perimeter and area of the first rectangle followed by those of the second rectangle.
Instructions
Use JOptionPane.showInputDialog ( ) for entering input values and JOptionPane.showMessageDialog ( ) for displaying the result. Import javax.swing.* package for using these classes.
Test Data
Test the program:
Using the following length and width values for the first object:
30, 20
Using the following length and width values for the first object:
60, 40
Test Output:
The output should look as below:
Values for the first object:
Length: 30
Width: 20
Perimeter: 100
Area: 600
Values for the second object:
Length: 60
Width: 40
Perimeter: 200
Area: 2400
Explanation / Answer
Rectangle.java :
package rect;
public class Rectangle
{
//instance variables
private double length;
private double width;
//Constructor
public Rectangle (double l, double w)
{
//initialize instance variables above using the parameters received
//in the constructor
length = l;
width = w;
}
//instance methods
public double getLength ( )
{
return length;
}
public double getWidth ( )
{
return width;
}
public double compArea (double l,double w )
{
double a;
//Calculating area
a = l*w;
//end code
return a;
}
public double compPerimeter (double l,double w )
{
//local variables
double p;
//calculating perimeter
p = 2*(l + w);
//end code
return p;
}
}
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TestRectangle.java :
package rect;
import rect.*;
import javax.swing.Box;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.*;
public class TestRectangle
{
public static void main (String [] args)
{
double l = 0,w=0;
System.out.println("Values for the first object:");
JFrame frame1 = new JFrame("Please enter length");
// prompt the user to enter the length
String length = JOptionPane.showInputDialog(frame1, "Enter length of object1");
JFrame frame2 = new JFrame("Please enter width");
// prompt the user to enter the length
String width = JOptionPane.showInputDialog(frame2, "Enter width of object1");
l = Double.parseDouble(length);
w = Double.parseDouble(width);
System.out.println("length: " + l);
System.out.println("width: " + w);
//input length and width values from the user for first object
//create the Rectangle object
Rectangle r1 = new Rectangle (l, w);
double area1 = r1.compArea(l, w);
double per1 = r1.compPerimeter(l, w);
System.out.println("Perimeter : "+per1);
System.out.println("Area : "+area1);
JFrame frame3 = new JFrame("Area and perimeter results");
JOptionPane.showMessageDialog(frame3, per1, "the results of lenth.", JOptionPane.PLAIN_MESSAGE);
JOptionPane.showMessageDialog(frame3, area1, "The result of perimeter.", JOptionPane.PLAIN_MESSAGE);
//input length and width values from the user for second object
//create the second Rectangle object
System.out.println("Values for the second object:");
JFrame frame4 = new JFrame("Please enter length");
// prompt the user to enter the length
String length1 = JOptionPane.showInputDialog(frame4, "Enter length of object2");
JFrame frame5 = new JFrame("Please enter width");
// prompt the user to enter the length
String width1 = JOptionPane.showInputDialog(frame2, "Enter width of object2");
l = Double.parseDouble(length1);
w = Double.parseDouble(width1);
System.out.println("length: " + l);
System.out.println("width: " + w);
Rectangle r2 = new Rectangle (l, w);
double area2 = r2.compArea(l, w);
double per2 = r2.compPerimeter(l, w);
//Call methods of Rectangle objects to find values of
//display the results
System.out.println("Perimeter : "+per2);
System.out.println("Area : "+area2);
JFrame frame7 = new JFrame("Area and perimeter results");
JOptionPane.showMessageDialog(frame7, per2, "the results of lenth.", JOptionPane.PLAIN_MESSAGE);
JOptionPane.showMessageDialog(frame7, area2, "The result of perimeter.", JOptionPane.PLAIN_MESSAGE);
}
}
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