@Test
  public void testRowCount() throws InterruptedException, ExecutionException {
    assertEquals(COUNT,
      AsyncAggregationClient
        .rowCount(TABLE, new LongColumnInterpreter(), new Scan().addColumn(CF, CQ)).get()
        .longValue());

    // Run the count twice in case some state doesn't get cleaned up inside AsyncTableImpl
    // on the first time.
    assertEquals(COUNT,
      AsyncAggregationClient
        .rowCount(TABLE, new LongColumnInterpreter(), new Scan().addColumn(CF, CQ)).get()
        .longValue());
  }
Same as TestAsyncAggregationClient, except that {@link AsyncTableImpl} is involved in addition to
{@link RawAsyncTableImpl}. Exercises the code paths in {@link AsyncTableImpl#coprocessorService}.
hbase-endpoint/src/test/java/org/apache/hadoop/hbase/client/TestAsyncAggregationClientWithCallbackThreadPool.java