@Override
    public JoinUtil.JoinResult setFromOther(ReusableGetAdaptor other) throws HiveException {
      assert other instanceof GetAdaptor;
      GetAdaptor other2 = (GetAdaptor)other;
      nulls = other2.nulls;
      currentKey = other2.currentKey;
      return currentValue.setFromOutput(other2.output);
    }
Implementation of ReusableGetAdaptor that has Output for key serialization; row
container is also created once and reused for every row.
ql/src/java/org/apache/hadoop/hive/ql/exec/persistence/HybridHashTableContainer.java