Creating an Alert Dialog Box

import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;
public class DisplayAlert extends MIDlet implements CommandListener
{
private Display display;
private Alert alert;
private Form form;
private Command exit;
private boolean exitFlag;
public DisplayAlert()
{
exitFlag = false;
display = Display.getDisplay(this);
exit = new Command("Exit", Command.SCREEN, 1);
form = new Form("Throw Exception");
form.addCommand(exit);
form.setCommandListener(this);
}
public void startApp()
{
display.setCurrent(form);
}
public void pauseApp()
{
}
public void destroyApp(boolean unconditional)
throws MIDletStateChangeException
{
if (unconditional == false)
{
throw new MIDletStateChangeException();
}
}
public void commandAction(Command command, Displayable displayable)
{
if (command == exit)
{
try
{
if (exitFlag == false)
{
alert = new Alert("Busy", "Please try again.",
null, AlertType.WARNING);
alert.setTimeout(Alert.FOREVER);
display.setCurrent(alert, form);
destroyApp(false);
}
else
{
destroyApp(true);
notifyDestroyed();
}
}
catch (MIDletStateChangeException exception)
{
exitFlag = true;
}
}
}
}