public void setReporter(Reporter rep) {
    reporter = rep;

    for (Operator<? extends OperatorDesc> op : childOperators) {
      op.setReporter(rep);
    }
  }
This function is not named getId(), to make sure java serialization does
NOT serialize it. Some TestParse tests will fail if we serialize this
field, since the Operator ID will change based on the number of query
tests.
ql/src/java/org/apache/hadoop/hive/ql/exec/Operator.java