import javax.swing.*;
import java.awt.*;

class JFlash extends JFrame implements Runnable {

    private JLabel label;

    public JFlash(String aString) {
	super(aString);
    }

    public void run() {
	setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        //Add the ubiquitous "Hello World" label.
        label = new JLabel();
	label.setFont(label.getFont().deriveFont((float)44));
	label.setOpaque(true);
	label.setBackground(new Color(0,51,0));
	label.setForeground(Color.RED);
	label.setHorizontalAlignment(SwingConstants.CENTER);
	
        getContentPane().add(label);

        //Display the window.
        pack();	
	setSize(500,200);
	setVisible(true);
    }

    public void flash(final String aString) {
	try {
	    SwingUtilities.invokeAndWait(new Runnable() {
		    public void run() {
			label.setText(aString);
		    }});
	    Thread.sleep(1000);
	    SwingUtilities.invokeAndWait(new Runnable() {
		    public void run() {
			label.setText("");
		    }});
	}
	catch (Exception e) {
	    e.printStackTrace();
	}
    }

    public static void main(String[] args) {
	SwingUtilities.invokeLater(new JFlash("Cremona"));
    }
}