Java Programing laungage

/*
 * Save as a addNumberBox.java
 */
package r4r.Mobile.Basic;
import javax.microedition.lcdui.*;
import javax.microedition.midlet.*;
/**
 * @author R4R
 */
public class addNumberBox extends MIDlet {
 /* -- Private Field -- */
 private Display display;
 private TextBox numberBox;
 private Command exit;
 /* -- Default constructor -- */
 public addNumberBox() {
 display = Display.getDisplay(this);
 numberBox = new TextBox("Write Number into 
		TextBox", "", 40, TextField.NUMERIC);
 exit = new Command("EXIT", Command.EXIT, 1);
 numberBox.addCommand(exit);
 }
				
 public void startApp() {
 numberBox.setCommandListener(new CommandListener() {
 public void commandAction(Command c, Displayable d) {
 if (c == exit) {
 destroyApp(true); 
 notifyDestroyed();
 }
 }
 });
 display.setCurrent(numberBox);
 }
 public void pauseApp() {
 }
 public void destroyApp(boolean unconditional) {
 }
}