3. a) Develop an applet in Java that displays a simple message. b) Develop an applet in Java that receives an integer in one text field, and computes its factorial Value and returns it in another text field, when the button named “Compute” is clicked.

 a)      Develop an applet in Java that displays a simple message.

Program:

import java.awt.*;

import java.applet.Applet;

/* <applet code="SimpleApplet" width=300 height=50> </applet> */

public class SimpleApplet extends Applet

{

 public void paint(Graphics g)

 {

 g.drawString ("A Simple Applet",100, 100);

 }

}

 

Execution:

C:\Users\vits\Desktop\java> javac  SimpleApplet.java

 

C:\Users\vits\Desktop\java>appletviewer  SimpleApplet.java

 

Output:

 

 

b)      Develop an applet in Java that receives an integer in one text field, and computes its factorial Value and returns it in another text field, when the button named “Compute” is clicked.

Program:

import java.awt.*;

import java.awt.event.*;

import java.applet.Applet;

/* <applet code="Fact" width=300 height=50> </applet> */

public class Fact extends Applet implements ActionListener

{

Label l1,l2; TextField t1,t2; Button b1;

public void init(){

l1=new Label("enter the value"); add(l1);

t1=new TextField(10); add(t1);

b1=new Button("Factorial"); add(b1); b1.addActionListener(this);

l2=new Label("Factorial of given no is"); add(l2);

t2=new TextField(10); add(t2);

}

public void actionPerformed(ActionEvent e)

{

if(e.getSource()==b1)

{

int fact=fact(Integer.parseInt(t1.getText())); t2.setText(String.valueOf(fact));

}

}

int  fact(int f)

{

int  s=0;

if(f==0)

 return 1;

else

return  f*fact(f-1);

}

}

 

Execution:

C:\Users\vits\Desktop\java>javac   Fact.java

 

C:\Users\vits\Desktop\java>appletviewer   Fact.java

 

Output: