Guava eventbus有订阅者吗？

Question

Is it possible to detect if an Guava Eventbus has one or more subscribers for a specific event?

I'm using Guava EventBus to broadcast received messages through the application. Sometimes i forget to register a class or forget the @Subscribe annotation.

It would be nice if i could detect this and write a warning to the log, but while going through the javadocs i couldn't find an lead.

Answer 1

Going through the javadocs did the trick: DeadEvent https://google.github.io/guava/releases/23.0/api/docs/com/google/common/eventbus/DeadEvent.html

@Subscribe
  public void handleDeadEvent(DeadEvent deadEvent) {
    log.debug("no subscribers!: "+deadEvent);
  }