A special subscriber that receives all events published to
EventBus. This is always registered with eventbus
but is disabled. In order to enable this subscriber call
EventBus.enableCatchAllSubscriber(java.util.concurrent.BlockingQueue)
with the sink (receiver) for all events.
This subscriber will only call
BlockingQueue.offer(Object) on this sink to avoid any sort
of blocking. Any events for which the offer call fails are rejected.
As any other
EventBus subscriber, this subscriber is async i.e. any events received by this subscriber are
pushed by the eventbus in async mode. The queue size for this is
SUBSCRIBER_QUEUE_SIZE and
there is no batching done for events to reduce memory overheads.