@Override
  public void write(DataOutput dataOutput) throws IOException {
    if (null != rowId) {
      dataOutput.writeBoolean(true);
      dataOutput.writeUTF(rowId);
    } else {
      dataOutput.writeBoolean(false);
    }
    int size = tuples.size();
    dataOutput.writeInt(size);
    for (ColumnTuple tuple : tuples) {
      Text cf = tuple.getCf(), cq = tuple.getCq();
      dataOutput.writeInt(cf.getLength());
      dataOutput.write(cf.getBytes(), 0, cf.getLength());
      dataOutput.writeInt(cq.getLength());
      dataOutput.write(cq.getBytes(), 0, cq.getLength());
      byte[] value = tuple.getValue();
      dataOutput.writeInt(value.length);
      dataOutput.write(value);
    }
  }
@return byte [] value for first tuple containing fam and qual or null if no match.
accumulo-handler/src/java/org/apache/hadoop/hive/accumulo/AccumuloHiveRow.java