public boolean isAlertEventReceived(Class<? extends AlertEvent> clazz) {
    if (!m_receivedAlertEvents.containsKey(clazz)) {
      return false;
    }

    return m_receivedAlertEvents.get(clazz).size() > 0;
  }
Gets whether an event of the specified class was received.

@param clazz
@return
ambari-server/src/test/java/org/apache/ambari/server/events/MockEventListener.java