Why isn't System.exit(0) used from an Applet

I am trying to figure out why the System.exit(0) method isn't used for an applet. Is it because an applet isn't an application (which is why the public static void main(String args[]))?
I have noticed when if I include System.exit(0) I will get an compilation error.
Is there someplace in the Java Tutorial that explains this?
thanks

You can put it in, but if you run it in a browser, it
will kill the browser and all its windowsThat is if the applet is signed. I have also noticed this behaviour and I think it is pretty weird. It looks like a bug to me.

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Why won't System.exit(0) work?

does System.exit(0); work with an event handler?
I'm making a quit menu button, and I want my program to quit when it is clicked...unfortunately, System.exit(0); is not working...can soemone please help?
thanks!

here's all mmy code......i'm really at a loss...i can't figure anything out......
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.io.*;
import java.util.*;
public class SafetyMapView extends JFrame {
     // These are the tiles and buttons
     private JPanel               tiles;
     private JButton[]          buttons;
     private JCheckBox           editWallsButton;
     private JCheckBox           selectExitsButton;
     private JButton           computePlanButton;
     private JCheckBox           showDistancesButton;
     private JButton           resetButton;
     private JMenuBar          theMenuBar;
     private JMenu               fileM;
     private JMenuItem          openM,saveM,quitM;
     private JFileChooser      showIt;
     public void setJMenuBar(JMenuBar aMenuBar){theMenuBar=aMenuBar;}
     public JButton getFloorTileButton(int i) { return buttons; }
     public JPanel getTilePanel() { return tiles; }
     public JCheckBox getEditWallsButton() { return editWallsButton; }
     public JCheckBox getSelectExitsButton() { return selectExitsButton; }
     public JButton getComputePlanButton() { return computePlanButton; }
     public JCheckBox getShowDistancesButton() { return showDistancesButton; }
     public JButton getResetButton() { return resetButton; }
     public JFileChooser getJFileChooser() { return showIt; }
     public JMenuItem getOpen() { return openM;}
     public JMenuItem getSave() { return saveM;}
     public JMenuItem getQuit() { return quitM;}
     // This constructor builds the panel
     public SafetyMapView(String title, FloorPlan floorPlan) {
          super(title);
          // Create the panel with the floor tiles on it
          createFloorPlanPanel(floorPlan);
          // Layout the rest of the window's components
setupComponents();
setDefaultCloseOperation(EXIT_ON_CLOSE);
setSize(600, 500);
setVisible(true);
// Create the panel to contain the buttons that display the floor plan
private void createFloorPlanPanel(FloorPlan floorPlan) {
     // Setup the panel with the buttons
buttons = new JButton[floorPlan.size()*floorPlan.size()];
tiles = new JPanel();
tiles.setLayout(new GridLayout(floorPlan.size(),floorPlan.size()));
          // Add the buttons to the tile panel
for (int r=0; r<floorPlan.size(); r++) {
     for (int c=0; c<floorPlan.size(); c++) {
          int i = r * floorPlan.size() + c;
          buttons[i] = new JButton();
          buttons[i].setBorder(BorderFactory.createLineBorder(Color.lightGray));
          buttons[i].setBackground(Color.white);
          tiles.add(buttons[i]);
     public void setOpenHandler(java.awt.event.ActionListener x){
     /*public void setSaveHandler(java.awt.event.ActionListener x){
               int option = 0;
               java.io.File sel = null;
               java.io.File[] files = null;
               String filename = null;
               javax.swing.JFileChooser chsr = new javax.swing.JFileChooser();
               option = chsr.showSaveDialog(null);
               switch (option)
               case javax.swing.JFileChooser.APPROVE_OPTION :
               //do something
                    a.dispose();
                    break;
               case javax.swing.JFileChooser.CANCEL_OPTION :
               sel = null;
               break;
               case javax.swing.JFileChooser.ERROR :
               sel = null;
               break;
               default :
               sel = null;
               break;
               chsr.setEnabled(false);
               //do something
               return;
               //DO something...//
// Here we add all the components to the window accordingly
private void setupComponents() {
     // Layout the components using a gridbag
GridBagLayout layout = new GridBagLayout();
GridBagConstraints layoutConstraints = new GridBagConstraints();
getContentPane().setLayout(layout);
// Add the tiles
layoutConstraints.gridx = 0; layoutConstraints.gridy = 1;
layoutConstraints.gridwidth = 1; layoutConstraints.gridheight = 7;
layoutConstraints.fill = GridBagConstraints.BOTH;
layoutConstraints.insets = new Insets(2, 2, 2, 2);
layoutConstraints.anchor = GridBagConstraints.NORTHWEST;
layoutConstraints.weightx = 1.0; layoutConstraints.weighty = 1.0;
layout.setConstraints(tiles, layoutConstraints);
getContentPane().add(tiles);
JMenuBar myMenuBar = new JMenuBar();
layoutConstraints.gridx = 0; layoutConstraints.gridy = 0;
layoutConstraints.gridwidth = layoutConstraints.gridheight = 1;
layoutConstraints.fill=GridBagConstraints.NONE;
layoutConstraints.insets = new Insets(2, 2, 2, 2);
layoutConstraints.anchor = GridBagConstraints.NORTHWEST;
layoutConstraints.weightx = 0.0; layoutConstraints.weighty = 0.0;
layout.setConstraints(myMenuBar, layoutConstraints);
          JMenu fileMenu = new JMenu("File");
          myMenuBar.add(fileMenu);
          fileMenu.setMnemonic('F');
          JMenuItem openM = new JMenuItem("Open Floor Plan");
          fileMenu.add(openM);
          openM.setMnemonic ('O');
          JMenuItem saveM = new JMenuItem("Save Floor Plan");
          fileMenu.add(saveM);
          saveM.setMnemonic ('S');
          JMenuItem quitM = new JMenuItem("Quit");
          fileMenu.add(quitM);
          quitM.setMnemonic ('Q');
          getContentPane().add(myMenuBar);
public static void main(String args[]){
     //try{
     new SafetyMapView("Fire Safety Routes", FloorPlan.example1());
     //catch(java.io.FileNotFoundException e){
     //     e.printStackTrace();
I cut out the parts where all the other buttons are being added to the layout cuz it was really relaly long....

WHY can't I access my database from an applet???????????

The security code won't let my applet access its own database (from its own server)..
I'm using getDocumentBase()
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I keep getting :
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This applet crap is really starting to piss me off. I can see why they came out with JSP.
All I need to do is access my database, update it, etc. It kind of defeats the purpose of being able to do jdbc from applets if you can't even access the database on your own damn server.
If you all don't have a clue, I'm freakin switching to PHP--I'm tired of this crap-I was thinking Java was a damn good language until I hit applets.

The simple answer to your question is: Because of security concerns.
The somewhat longer answer is that directly accessing a database from an applet is generally not a good idea. A lot of security-critical code like DB username/password must be hidden in the applet which potentially can be downloaded (and disassembled) by anyone that hits your webpage. Maybe you do an intranet solution with trusted users but that is not what applets were originally designed for.
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If that is not the way you want to do it, make sure that all client policy files (yes, on the browser machine) contain the permissions that your applet needs.

Why isn't the DefaultItemRenderer class inherited from Skin?

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<?xml version="1.0" encoding="utf-8"?>

The DefaultItemRenderer.mxml is skin class for ItemRenderer.cs,but isn't inherited from skin?

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<Edited by Host>

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Thanks for your replies.
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There's a fair bit to it, and you should refer to the appropriate java Tutorials. Bascially you create a .policy file and install a sercurity manager with:
System.setSecurityManger(new SecurityManager());The policy file grants a set of permissions to various "code sources", basically each codesource is a classpath entry. You could grant "AllPermissions" to your own code, and a more restricted set of permissions to the application you're running. But you can't subtract permissions, i.e. you can't say "this code can do anything except call System.exit().
I doubt this is going to provide you with a good solution. It's tiresome to set up, and when the client app called System.exit it would crash, which might not result in a clean status.
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I'm wondering if anyone can tell me why javac (J2SE v1.4.2) seems to ignore "System.exit(int)" (alternately, "Runtime.getRuntime().exit(int)") for the pursposes of determining possible variable access before an initialization.
For example, consider the following code:
/*01*/ public class C {
/*02*/    public void foo() throws Exception {
/*03*/      C obj;
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System.exit() doesn't have the same "special" meaning
to the compiler as "break", "return", or "throw" do.
As far as the compiler sees, you are simply calling a
method in your exception handler; it doesn't know
that there will be no return from that method. Sure,
the compiler could special-case System.exit(), but
then you'd still see this same problem if you came up
with your own wrapper method that calls
System.exit().. the compiler in general doesn't (and
shouldn't) assume that a method call will terminate
the app.I understand that "System.exit(int)" is merely a method from the perspective of the compiler, but it is a rather special method (actually the "Runtime" version, for which the "System" version is merely a wrapper) with respect to correct program execution, calculated during the various traces that are done during compilation. And wrapping "System.exit(int)" with another method wouldn't make any difference to the calculation if it was considered, from the perspective of compilation, an uncaught (implicitly declared non-Runtime) exception. Besides, there must be some execution sequence within "Runtime.exit(int)" that serves, essentially, the same function as an "exit" keyword.
What's wrong with supplying a default value when you
declare the variable?Absolutely nothing, except that it isn't necessary. I typically do so anyway, and only came across this "feature" of javac during a lapse of my coding standards.

Why isn't System.exit(0) used from an Applet

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