Design an AWT application to calculate the factorial of a number.

Source Code:-

import java.awt.*;

import java.awt.event.*;

class Factorial extends Frame implements ActionListener

{

          TextField tf1,tf2;

          public Factorial()

          {

                   setLayout(new FlowLayout());

                   Label lb1=new Label("Enter Number:");

                   Label lb2=new Label("Factorial is:");

 

                   tf1=new TextField(15);

                   tf2=new TextField(15);

                   Button btn1=new Button("Calculate");

 

                   add(lb1);

                   add(tf1);

                   add(lb2);

                   add(tf2);

                   add(btn1);

 

                   btn1.addActionListener(this);

 

          }

 

          public static void main(String arg[])

          {

 

                   Factorial fr=new Factorial();

                   fr.setSize(300,300);

                   fr.setTitle("Calculate Factorial");

                   fr.setVisible(true);

 

          }

 

          public void actionPerformed(ActionEvent ae)

 

          {

 

                   int n,f=1,i;

                   n= Integer.parseInt(tf1.getText());

                   for(i=1;i<=n;i++)

 

                   {

                             f=f*i;

                   }

 

                   tf2.setText(" "+f);

          }

 

}

Output :-