applet array

[bluebird123]

how to creat an applet array of 4 to get integers from the user and display the total marks of those nos. i tried but loops are not working. here is my program.

import java.awt.*;
import java.applet.*;
import java.awt.event.*;

public class test extends Applet implements ActionListener
{
Label  l1,l2;
TextField  t1,t2;
Button b1;

public void init()
{
GridLayout x=new GridLayout(3,2,5,5);
setLayout(x);
//row1
l1=new Label("Enter a Number:");
add(l1);
t1=new TextField();
add(t1);
//row2
l2=new Label("Total");
add(l2);
t2=new TextField();
add(t2);
b1=new Button("ADD Numbers");
add(b1);
b1.addActionListener(this);

}
public void actionPerformed(ActionEvent e)
{
int tot,i,n;
int num[];
num = new int[4];
tot=0;i=0;n=0;

while (i<num.length)
{
if  (e.getSource()==b1)
{
n=Integer.parseInt(t1.getText());
num[i]=n;
tot=tot+n;
t2.setText(String.valueOf(tot));
t1.setText(" ");
i++;
}
}
}
}
/*if (e.getSource()==b1)
    {
do
    {
    i=i+1;

tot=tot+num[i];
t2.setText(String.valueOf(tot));
//t1.setText(" ");
}while (i<num.length);
*/
//}