Swing/ToolTipAfterMouseWheelEvent のバックアップ(No.2)

class TooltipList<E> extends JList<E> {
  protected TooltipList(ListModel<E> m) {
    super(m);
  }

  @Override public String getToolTipText(MouseEvent e) {
    Point p0 = e.getPoint();
    Point p1 = getMousePosition();
    if (p1 != null && !p1.equals(p0)) {
      int i = locationToIndex(p1);
      Rectangle cellBounds = getCellBounds(i, i);
      if (i >= 0 && cellBounds != null && cellBounds.contains(p1.x, p1.y)) {
        MouseEvent event = new MouseEvent(
            e.getComponent(),
            MouseEvent.MOUSE_MOVED,
            e.getWhen(),
            e.getModifiers(),
            p1.x,
            p1.y,
            e.getClickCount(),
            e.isPopupTrigger()
        );
        return super.getToolTipText(event);;
      }
    }
    return super.getToolTipText(e);
  }

  @Override public Point getToolTipLocation(MouseEvent e) {
    Point p0 = e.getPoint();
    Point p1 = getMousePosition();
    if (p1 != null && !p1.equals(p0)) {
      int i = locationToIndex(p1);
      Rectangle cellBounds = getCellBounds(i, i);
      if (i >= 0 && cellBounds != null && cellBounds.contains(p1.x, p1.y)) {
        return new Point(p1.x, p1.y + cellBounds.height);
      }
    }
    return null;
  }
}