public void testAggregateCountReduce (
      int batchSize,
      Iterable<Long> values,
      Object expected) throws HiveException {

    @SuppressWarnings("unchecked")
    FakeVectorRowBatchFromLongIterables fdr = new FakeVectorRowBatchFromLongIterables(batchSize,
        values);
    testAggregateCountReduceIterable (fdr, expected);
  }
Unit test for the vectorized GROUP BY operator.
ql/src/test/org/apache/hadoop/hive/ql/exec/vector/TestVectorGroupByOperator.java