public static boolean matchingColumn(final Cell left, final byte[] fam, final int foffset,
    final int flength, final byte[] qual, final int qoffset, final int qlength) {
    if (!matchingFamily(left, fam, foffset, flength)) {
      return false;
    }
    return matchingQualifier(left, qual, qoffset, qlength);
  }
Finds if the start of the qualifier part of the Cell matches <code>buf</code>
@param left       the cell with which we need to match the qualifier
@param startsWith the serialized keyvalue format byte[]
@return true if the qualifier have same staring characters, false otherwise
hbase-common/src/main/java/org/apache/hadoop/hbase/PrivateCellUtil.java