}
  public int columnAtPoint(Point point)  {    int x0 = getLocation().x;    int ncols = getColumnCount();    Dimension gap = getIntercellSpacing();    TableColumnModel cols = getColumnModel();    int x = point.x;        for (int i = 0; i < ncols; ++i)      {        int width = cols.getColumn(i).getWidth() + (gap == null ? 0 : gap.width);        if (0 <= x && x < width)          return i;        x -= width;        }        return -1;  }