@Override
    public void afterCreate(EntryEvent event) {
      String key = (String) event.getKey();
      if (key.equals(LAST_KEY)) {
        synchronized (LOCK) {
          lastKeyArrived = true;
          LOCK.notifyAll();
        }
      } else {
        actualNoEvents++;
      }

    }
In this test do a create , update , update & destroy. The client should receive 3 callbacks (
craete , conflated update & destroy).
geode-core/src/distributedTest/java/org/apache/geode/internal/cache/ha/HAConflationDistributedTest.java