public StatsAggregator getStatsAggregator() {

    return (StatsAggregator) ReflectionUtils.newInstance(aggregatorImplementation, jobConf);
  }
Returns a Stats Aggregator implementation class for the IStatsAggregator interface
For example HBaseStatsAggregator for the HBase implementation
ql/src/java/org/apache/hadoop/hive/ql/stats/StatsFactory.java