public static ExtendedCell createFirstOnRowCol(final Cell cell) {
    if (cell instanceof ByteBufferExtendedCell) {
      return new FirstOnRowColByteBufferExtendedCell(
        ((ByteBufferExtendedCell) cell).getRowByteBuffer(),
        ((ByteBufferExtendedCell) cell).getRowPosition(), cell.getRowLength(),
        HConstants.EMPTY_BYTE_BUFFER, 0, (byte) 0,
        ((ByteBufferExtendedCell) cell).getQualifierByteBuffer(),
        ((ByteBufferExtendedCell) cell).getQualifierPosition(), cell.getQualifierLength());
    }
    return new FirstOnRowColCell(cell.getRowArray(), cell.getRowOffset(), cell.getRowLength(),
      HConstants.EMPTY_BYTE_ARRAY, 0, (byte) 0, cell.getQualifierArray(), cell.getQualifierOffset(),
      cell.getQualifierLength());
  }
Create a Cell that is smaller than all other possible Cells for the given Cell's row.
@return First possible Cell on passed Cell's row.
hbase-common/src/main/java/org/apache/hadoop/hbase/PrivateCellUtil.java