docs: void process(EventEnvelope envelope) {
          Object event = getEvent(envelope);
          String serviceName = envelope.getServiceName();
          EventPublishingService<Object, Object> service = eventService.nodeEngine.getService(serviceName);
          Registration registration = getRegistration(envelope, serviceName);
          if (registration == null) {
              return;
          }
          service.dispatchEvent(event, registration.getListener());
      }