make JDialog disappear after a few seconds

make JDialog disappear after a few seconds

I have a JDialog class:
public class Test extends JDialog {
private JPanel panel = new JPanel ( new BorderLayout() );
public Test () {
super(frame,"Evidenziatore");
setDefaultCloseOperation(HIDE_ON_CLOSE);
setVisible(true);
add( panel, BorderLayout.CENTER );
}
}
What I'd like to do is to make JDIalog disappear after user has exited
from that JDialog or from the JPanel for a few seconds, e.g. using
mouseEntered or mouseExited events or after user has clicked somewhere
else. I mean something like chrome or firefox search window, avaible using
ctrl-f.
How can I do that?
Thanks