@Override
  public void initializeEventDispatcher() {
    if (logger.isDebugEnabled()) {
      logger.debug(" Creating the GatewayEventCallbackDispatcher");
    }
    dispatcher = new GatewaySenderEventCallbackDispatcher(this);
  }
use in concurrent scenario where queue is to be shared among all the processors.
geode-core/src/main/java/org/apache/geode/internal/cache/wan/parallel/ParallelGatewaySenderEventProcessor.java