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) {
    }
}