Listing A—HelloJ2ME

import javax.microedition.midlet.*;

import javax.microedition.lcdui.*;

 
public class HelloJ2ME extends MIDlet implements CommandListener

{

  private Display display;

  private TextField tfHello;

  private Command cmExit;

  private Form fmMain;
 

  public HelloJ2ME()

  {

    //Get a handle to the display object

    display = Display.getDisplay(this);
 

    //Create the main form

    fmMain = new Form("HelloJ2ME");
 

    //Create the exit command button

    cmExit = new Command("Exit", Command.SCREEN,1);
 

    //Create a single-line text field 15 characters long

    //with the label "Text"

    tfHello = new TextField("Text","Hello World!",15,TextField.ANY);
  

    //Add the components to the form and set up the

    //command listener

    fmMain.addCommand(cmExit);

    fmMain.append(tfHello);

    fmMain.setCommandListener(this);  

  }
 

  public void startApp()

  {

    //set fmMain as the active object

    display.setCurrent(fmMain);

  }
 

  public void pauseApp()

  { /*app is being paused*/ }
 

  public void destroyApp(boolean unconditional)

  { /*app is being ended*/ }
 

  public void commandAction(Command c, Displayable s)

  {

    //click on the Exit button

    if (c == cmExit)

    {

       //destroyApp must be called manually

       destroyApp(false);

       //ask the manager to end the app

       notifyDestroyed();

    }

  }

}