/**
* This implementation handles the following flags, in addition to those described in the {@link
* SubscriptionManager} interface:
*
* <ul>
* <li>subscriberExecutionManagerTag - a tag to pass to execution manager (without setting any
* execution semantics / TaskPreprocessor); if not supplied and there is a subscriber, this
* will be inferred from the subscriber and set up with SingleThreadedScheduler (supply this
* flag with value null to prevent any task preprocessor from being set)
* <li>eventFilter - a Predicate<SensorEvent> instance to filter what events are delivered
* </ul>
*
* @see SubscriptionManager#subscribe(Map, Entity, Sensor, SensorEventListener)
*/
public synchronized <T> SubscriptionHandle subscribe(
Map<String, Object> flags,
Entity producer,
Sensor<T> sensor,
SensorEventListener<? super T> listener) {
Subscription s = new Subscription(producer, sensor, listener);
s.subscriber = flags.containsKey("subscriber") ? flags.remove("subscriber") : listener;
if (flags.containsKey("subscriberExecutionManagerTag")) {
s.subscriberExecutionManagerTag = flags.remove("subscriberExecutionManagerTag");
s.subscriberExecutionManagerTagSupplied = true;
} else {
s.subscriberExecutionManagerTag =
s.subscriber instanceof Entity
? "subscription-delivery-entity-"
+ ((Entity) s.subscriber).getId()
+ "["
+ s.subscriber
+ "]"
: s.subscriber instanceof String
? "subscription-delivery-string[" + s.subscriber + "]"
: s != null ? "subscription-delivery-object[" + s.subscriber + "]" : null;
s.subscriberExecutionManagerTagSupplied = false;
}
s.eventFilter = (Predicate) flags.remove("eventFilter");
s.flags = flags;
if (LOG.isDebugEnabled())
LOG.debug(
"Creating subscription {} for {} on {} {} in {}",
new Object[] {s, s.subscriber, producer, sensor, this});
allSubscriptions.put(s.id, s);
LanguageUtils.addToMapOfSets(
subscriptionsByToken, makeEntitySensorToken(s.producer, s.sensor), s);
if (s.subscriber != null) {
LanguageUtils.addToMapOfSets(subscriptionsBySubscriber, s.subscriber, s);
}
if (!s.subscriberExecutionManagerTagSupplied && s.subscriberExecutionManagerTag != null) {
((BasicExecutionManager) em)
.setTaskSchedulerForTag(s.subscriberExecutionManagerTag, SingleThreadedScheduler.class);
}
return s;
}
