@Override
  public ReturnCode filterCell(final Cell c) {
    // Check if the column and qualifier match
    if (!CellUtil.matchingColumn(c, this.columnFamily, this.columnQualifier)) {
      // include non-matches for the time being, they'll be discarded afterwards
      return ReturnCode.INCLUDE;
    }
    // If it doesn't pass the op, skip it
    if (comparator != null && compareValue(getCompareOperator(), comparator, c))
      return ReturnCode.SKIP;

    stampSet.add(c.getTimestamp());
    if (dropDependentColumn) {
      return ReturnCode.SKIP;
    }
    return ReturnCode.INCLUDE;
  }
Returns true if we should drop the dependent column, false otherwise
hbase-client/src/main/java/org/apache/hadoop/hbase/filter/DependentColumnFilter.java