code: public static void attachOverlay(JComponent overlay, JComponent overlayTarget, int center, int xOffset, int yOffset)
      {
          new OverlayHelper(overlay, overlayTarget, center, xOffset, yOffset);
      }
docs: Attaches an overlay to the specified component.
  
  @param overlay       the overlay component
  @param overlayTarget the component over which <code>overlay</code> will be
  attached
  @param center        position relative to <code>overlayTarget</code> that overlay
  should be centered. May be one of the
  <code>SwingConstants</code> compass positions or
  <code>SwingConstants.CENTER</code>.
  @param xOffset       x offset from center
  @param yOffset       y offset from center
  @see SwingConstants