org.apache.brooklyn.api.mgmt

Interface SubscriptionManager

All Known Implementing Classes:

AbstractSubscriptionManager, LocalSubscriptionManager, QueueingSubscriptionManager

public interface SubscriptionManager

The management interface for subscriptions. Different implementations will handle entities subscribing and unsubscribing to SensorEvents and their delivery.

See Also:

SubscriptionContext

Method Summary

Modifier and Type	Method and Description
java.util.Set<SubscriptionHandle>	getSubscriptionsForEntitySensor(Entity source, Sensor<?> sensor) Return the subscriptions on a given source-sensor pair
java.util.Set<SubscriptionHandle>	getSubscriptionsForSubscriber(java.lang.Object subscriber) Return the subscriptions requested by a given subscriber
<T> void	publish(SensorEvent<T> event) Deliver a SensorEvent to all subscribed listeners.
<T> SubscriptionHandle	subscribe(Entity producer, Sensor<T> sensor, SensorEventListener<? super T> listener)
<T> SubscriptionHandle	subscribe(java.util.Map<java.lang.String,java.lang.Object> flags, Entity producer, Sensor<T> sensor, SensorEventListener<? super T> listener) Subscribe to Sensor data changes and events on a given Entity, supplying the SensorEventListener to invoke when they occur.
<T> SubscriptionHandle	subscribeToChildren(Entity parent, Sensor<T> sensor, SensorEventListener<? super T> listener)
<T> SubscriptionHandle	subscribeToChildren(java.util.Map<java.lang.String,java.lang.Object> flags, Entity parent, Sensor<T> sensor, SensorEventListener<? super T> listener) Subscribe to Sensor data changes and events on all children of a given Entity, supplying the SensorEventListener to invoke when they occur.
<T> SubscriptionHandle	subscribeToMembers(Group parent, Sensor<T> sensor, SensorEventListener<? super T> listener)
<T> SubscriptionHandle	subscribeToMembers(java.util.Map<java.lang.String,java.lang.Object> flags, Group parent, Sensor<T> sensor, SensorEventListener<? super T> listener) Subscribe to Sensor data changes and events on all members of a given Group, supplying the SensorEventListener to invoke when they occur.
boolean	unsubscribe(SubscriptionHandle subscriptionId) Unsubscribe the given subscription id.

Method Detail

subscribe

<T> SubscriptionHandle subscribe(java.util.Map<java.lang.String,java.lang.Object> flags,
                                 Entity producer,
                                 Sensor<T> sensor,
                                 SensorEventListener<? super T> listener)

Subscribe to Sensor data changes and events on a given Entity, supplying the SensorEventListener to invoke when they occur. The method returns an id which can be used to unsubscribe(SubscriptionHandle) later.

The listener callback is in-order single-threaded and synchronized on this object. In other words message delivery from a producer to a given subscriber is in publish order (or in the case of a late subscriber getting initial values, in subscribe order). The flags parameters can include the following:

• subscriber - object to identify the subscriber (e.g. entity, or console session uid)
• in future - control parameters for the subscription (period, minimum delta for updates, etc)

Parameters:

flags - optional parameters to be associated with the subscription

producer - entity to listen to, or null to listen to all entities

sensor - sensor channel of events to listen to, or null for all sensors from the given producer(s)

listener - callback to invoke when an event occurs

Returns:

an id for this subscription

See Also:

unsubscribe(SubscriptionHandle)

subscribe

<T> SubscriptionHandle subscribe(Entity producer,
                                 Sensor<T> sensor,
                                 SensorEventListener<? super T> listener)

See Also:

subscribe(Map, Entity, Sensor, SensorEventListener)

subscribeToChildren

<T> SubscriptionHandle subscribeToChildren(java.util.Map<java.lang.String,java.lang.Object> flags,
                                           Entity parent,
                                           Sensor<T> sensor,
                                           SensorEventListener<? super T> listener)

Subscribe to Sensor data changes and events on all children of a given Entity, supplying the SensorEventListener to invoke when they occur. The subscriptions will be created recursively for all children, and the same listener callback will be invoked for each sensor datum. The semantics are otherwise identical to the subscribe(Map, Entity, Sensor, SensorEventListener) method.

See Also:

subscribe(Map, Entity, Sensor, SensorEventListener)

subscribeToChildren

<T> SubscriptionHandle subscribeToChildren(Entity parent,
                                           Sensor<T> sensor,
                                           SensorEventListener<? super T> listener)

See Also:

subscribeToChildren(Map, Entity, Sensor, SensorEventListener)

subscribeToMembers

<T> SubscriptionHandle subscribeToMembers(java.util.Map<java.lang.String,java.lang.Object> flags,
                                          Group parent,
                                          Sensor<T> sensor,
                                          SensorEventListener<? super T> listener)

Subscribe to Sensor data changes and events on all members of a given Group, supplying the SensorEventListener to invoke when they occur. The subscriptions will be created recursively for all children, and the same listener callback will be invoked for each sensor datum. The semantics are otherwise identical to the subscribe(Map, Entity, Sensor, SensorEventListener) method.

See Also:

subscribe(Map, Entity, Sensor, SensorEventListener)

subscribeToMembers

<T> SubscriptionHandle subscribeToMembers(Group parent,
                                          Sensor<T> sensor,
                                          SensorEventListener<? super T> listener)

See Also:

subscribeToMembers(Map, Group, Sensor, SensorEventListener)

unsubscribe

boolean unsubscribe(SubscriptionHandle subscriptionId)

Unsubscribe the given subscription id.

Returns:

true if such a subscription was present (and it will now be removed)

See Also:

subscribe(Map, Entity, Sensor, SensorEventListener)

publish

<T> void publish(SensorEvent<T> event)

Deliver a SensorEvent to all subscribed listeners.

getSubscriptionsForSubscriber

java.util.Set<SubscriptionHandle> getSubscriptionsForSubscriber(java.lang.Object subscriber)

Return the subscriptions requested by a given subscriber

getSubscriptionsForEntitySensor

java.util.Set<SubscriptionHandle> getSubscriptionsForEntitySensor(Entity source,
                                                                  Sensor<?> sensor)

Return the subscriptions on a given source-sensor pair