Fazer joptionpane desaparecer

import java.awt.BorderLayout;
import java.util.Timer;
import java.util.TimerTask;
import javax.swing.JFrame;
import javax.swing.JLabel;

public class Principal{
	public static void main(String[] args) {
		new msgTimer().showMessage("Teste", 5000); //5 segundos
}
class msgTimer{
	JFrame FrameMsg;
	public void showMessage(String msg, int tempo){
		FrameMsg = new JFrame("Teste");
		FrameMsg.setLayout(new BorderLayout());
		JLabel l = new JLabel (msg);
		l.setAlignmentY(JLabel.CENTER_ALIGNMENT);
		FrameMsg.add(l, BorderLayout.CENTER);
		FrameMsg.setSize(200, 200);
		FrameMsg.setVisible(true);
		Timer t = new Timer();
		t.schedule(new TimerTask(){
			public void run() {
				try {
					FrameMsg.setVisible(false);
				} catch (Throwable e) {
					e.printStackTrace();
				}
			}}, tempo);
		}
	}