Close button in applet

Question

hi u see in the code that i have made a button an exit button and i did this code but when i run the code is fine but when i click the exit button it dos not clos the applet
import java.awt.*;
import java.awt.event.*;
import java.applet.*;
import javax.swing.*;
public class assignment2_1 extends Applet implements ActionListener {
     JTextField ID, Mark;
          JLabel IdLabel, MarkLabel;
     JButton ExitButton;
JTextArea Disply;
String stnum;
int studentnum;
int stid;
int assimak;
public void init() {
GridBagLayout GBL = new GridBagLayout();
     GridBagConstraints cr= new GridBagConstraints();
     setLayout(GBL);
     setBackground(Color.lightGray);
     cr.weightx=cr.weighty = 2.0;
     cr.gridx=1; cr.gridy =2;
     cr.gridheight = 1; cr.gridwidth = 2;
add(IdLabel=new JLabel("Enter Student ID"),cr);
//     IdLabel.setBackground(Color.lightGray);
     cr.weightx=cr.weighty = 2.0;
     cr.gridx=5; cr.gridy =2;
     cr.gridheight = 1; cr.gridwidth = 2;
     add(ID = new JTextField(9),cr);
cr.weightx=cr.weighty = 2.0;
     cr.gridx=1; cr.gridy =3;
     cr.gridheight = 1; cr.gridwidth = 2;
     add(MarkLabel=new JLabel("Enter Assignment Mark"),cr);
//     MarkLabel.setBackground(Color.lightGray);
cr.weightx=cr.weighty = 2.0;
cr.gridx=5; cr.gridy =3;
     cr.gridheight = 1; cr.gridwidth = 2;
     add(Mark=new JTextField(9),cr);
     Mark.addActionListener( this );
cr.weightx=cr.weighty = 2.0;
cr.gridx=1; cr.gridy =4;
     cr.gridheight = 1; cr.gridwidth = 2;
     add(Disply=new JTextArea(10, 20),cr);
     Disply.setEditable(false);
//     Disply.setBackground(Color.lightGray);
cr.weightx=cr.weighty = 1.0;
cr.gridx=5; cr.gridy =5;
     cr.gridheight = 1; cr.gridwidth = 2;
     add(ExitButton=new JButton("Exit"),cr);
     ExitButton.addActionListener( this );
/*     Container container = getContentPane();
          container.setLayout( new FlowLayout() );
     IdLabel = new JLabel("Enter Student ID ");
          container.add( IdLabel );
     ID = new JTextField(9);
          container.add( ID );
     MarkLabel = new JLabel("Enter Assignment Mark ");
          container.add( MarkLabel );
               Mark = new JTextField(5);
               Mark.addActionListener( this );
          container.add( Mark );
          Disply = new JTextArea( 10, 20);
          Disply.setEditable(false);
               container.add( Disply );
     ExitButton = new JButton("Exit");
     ExitButton.addActionListener( this );
          container.add( ExitButton );
stnum = JOptionPane.showInputDialog( "Enter total assignment" );
public void actionPerformed(ActionEvent evt) {
studentnum = Integer.parseInt( stnum );
     stid = Integer.parseInt(ID.getText());
          assimak = Integer.parseInt(Mark.getText());
if (evt.getSource() == Mark)
showStatus ("heeeea "+ studentnum);
     if (evt.getSource() == ExitButton )
          System.exit(0);

Answer 1

Are you trying to run this in a browser or using AppletRunner? I don't think you can close a browser window just by calling System.exit(). You have to find some way to close the browser.
Check for exceptions in the Java console.