@Override
        public int compare(Cell<?> cell1, Cell<?> cell2) {
            int thisRow = cell1.getRow();
            int otherRow = cell2.getRow();
            int cmp = (thisRow < otherRow ? -1 : (thisRow > otherRow ? 1 : 0));
            if (cmp == 0) {
                int thisCol = cell1.getColumn();
                int otherCol = cell2.getColumn();
                cmp = (thisCol < otherCol ? -1 : (thisCol > otherCol ? 1 : 0));
            }
            return cmp;
        }