import javax.swing.JOptionPane;

/**
 * Puts up a dialog box that says "Hello World."  The program
 * ends when the user closes the dialog box.  This is, perhaps,
 * the simplest possible GUI program.
 */
public class HelloWorldGUI1 {

    public static void main(String[] args) {
        JOptionPane.showMessageDialog( null, "Hello World!" );
    }

}