public CacheSerializableRunnable setTestHook() {
    SerializableRunnable sr = new CacheSerializableRunnable("TestHook") {
      @Override
      public void run2() {
        class CqQueryTestHook implements CqQueryImpl.TestHook {

          final CountDownLatch latch = new CountDownLatch(1);
          private int numEvents = 0;

          @Override
          public void pauseUntilReady() {
            try {
              logger.debug("CqQueryTestHook: Going to wait on latch until ready is called.");
              if (!latch.await(10, TimeUnit.SECONDS)) {
                fail("query was never unlatched");
              }
            } catch (Exception e) {
              fail("interrupted", e);
            }
          }

          @Override
          public void ready() {
            latch.countDown();
            logger.debug("CqQueryTestHook: The latch has been released.");
          }

          @Override
          public int numQueuedEvents() {
            return numEvents;
          }

          @Override
          public void setEventCount(int count) {
            logger.debug("CqQueryTestHook: Setting numEVents to: " + count);
            numEvents = count;
          }
        }
        CqQueryImpl.testHook = new CqQueryTestHook();
      }
    };
    return (CacheSerializableRunnable) sr;
  }
Test for events created during the CQ query execution. When CQs are executed using
executeWithInitialResults there may be possibility that the region changes during that time may
not be reflected in the query result set thus making the query data and region data
inconsistent.
geode-cq/src/distributedTest/java/org/apache/geode/cache/query/cq/dunit/CqDataUsingPoolDUnitTest.java