private void update(DropTargetDragEvent event) {
      JComponent component = getComponent(event);
      if (component != null) {
        Point location = new Point(event.getLocation());
        SwingUtilities.convertPointToScreen(location, component);
        if (Registry.is("ide.dnd.to.front")) {
          Window window = ComponentUtil.getWindow(component);
          if (window != null) window.toFront();
        }
        this.screen.setLocation(location);
        this.event = event;
        if (!timer.isRunning()) {
          LOG.debug("SmoothAutoScroller started");
          timer.start();
        }
      }
      else {
        this.event = null;
        if (timer.isRunning()) {
          LOG.debug("SmoothAutoScroller stopped");
          timer.stop();
        }
      }
    }
private void update(DropTargetDragEvent event)