@Override
  protected void closeOp(boolean abort) throws HiveException {
    conf.getGenericUDTF().close();
    super.closeOp(abort);
  }
forwardUDTFOutput is typically called indirectly by the GenericUDTF when
the GenericUDTF has generated output rows that should be passed on to the
next operator(s) in the DAG.

@param o
@throws HiveException
ql/src/java/org/apache/hadoop/hive/ql/exec/UDTFOperator.java