private int getCellAt(Point pnt) {
    if (mySelectedContainer == null) return -1;
    pnt = SwingUtilities.convertPoint(this, pnt, mySelectedContainer.getDelegee());
    return myIsRow ? mySelectedContainer.getGridRowAt(pnt.y) : mySelectedContainer.getGridColumnAt(pnt.x);
  }
private int getCellAt(Point pnt)