Java Programing laungage

/*
 * Save as a addAlert.java
 */
package r4r.Mobile.Basic;
import javax.microedition.lcdui.*;
import javax.microedition.midlet.*;
/**
 * @author R4R
 */
public class addAlert extends MIDlet implements CommandListener {
 /* -- private field -- */
 private Form form;
 private Display display;
 private Alert alert;
 private Command exit, launch;
 /* -- Default constructor -- */
 public addAlert() {
 display = Display.getDisplay(this);
 form = new Form("Add Alert into form");
 exit = new Command("EXIT", Command.EXIT, 1);
 launch = new Command("LAUNCH", Command.OK, 1);
 form.addCommand(exit);
 form.addCommand(launch);
 form.setCommandListener(this);
 }
 public void startApp() {
 // Request to MIDlet for setting the current Displayable object be made visible on the display.
 display.setCurrent(form);
 }
 public void pauseApp() {
 }
 public void destroyApp(boolean unconditional) {
 }
 public void commandAction(Command c, Displayable d) {
 if (c == exit) {
 destroyApp(true); // invoked MIDlet to terminate state
 notifyDestroyed(); // notify to MIDlet has entered into Destroyed state.
 } else if (c == launch) {
 activateAlert(); //invoked activeAlert() method
 form.removeCommand(launch); // removes a command from the form
 }
 }
 /* -- call activeAlert() method into commandAction -- */
 private void activateAlert() {
 alert = new Alert(" Error ", " -- Alert Launch for 5000 milliseconds -- ", null, AlertType.ALARM);
 alert.setTimeout(5000); //Set alert timeOut
 display.setCurrent(alert, form);
 }
}