20)Write a Java program to design a screen using Awt that will take a user name and password. If the user name and password are not same, raise an exception with appropriate message. User can have 3 login chances only. Use clear 7 button to clear the text boxes.


import java.awt.*;
import java.awt.event.*;
class InvalidPasswordException extends Exception
{
InvalidPasswordException()
{
System.out.println(” User name and Password is not same”);
}
}
public class PasswordDemo extends Frame implements ActionListener
{
Label uname,upass;
TextField nametext;
TextField passtext,msg;
Button login,Clear;
Panel p;
int attempt=0;
char c= ‘ * ‘ ;

public void login()
{
p=new Panel();
uname=new Label(“Use Name: ” ,Label.CENTER);
upass=new Label (“Password: “,Label.RIGHT);

nametext=new TextField(20);
passtext =new TextField(20);
passtext.setEchoChar(c);
msg=new TextField(10);
msg.setEditable(false);

login=new Button(“Login”);
Clear=new Button(“Clear”);
login.addActionListener(this);
Clear.addActionListener(this);

p.add(uname);
p.add(nametext);
p.add(upass);
p.add(passtext);
p.add(login);
p.add(Clear);
p.add(msg);
add(p);

setTitle(“Login “);
setSize(290,200);
setResizable(false);
setVisible(true);
}

public void actionPerformed(ActionEvent ae)
{
Button btn=(Button)(ae.getSource());
if(attempt<3)
{
if((btn.getLabel())==”Clear”)
{
nametext.setText(“”);
passtext.setText(“”);
}
if((btn.getLabel()).equals(“Login”))
{
try
{
String user=nametext.getText();
String upass=passtext.getText();

if(user.compareTo(upass)==0)
{
msg.setText(“Valid”);
System.out.println(“Username is valid”);
}
else
{
throw new InvalidPasswordException();
}
}
catch(Exception e)
{
msg.setText(“Error”);
}
attempt++;
}
}
else
{
System.out.println(“you are using 3 attempt”);
System.exit(0);
}
}
public static void main(String args[])
{
PasswordDemo pd=new PasswordDemo();
pd.login();
}
}

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