org.olat.core.util.event
Class AbstractEventBus

java.lang.Object
  org.olat.core.util.event.AbstractEventBus

All Implemented Interfaces:

EventBus

Direct Known Subclasses:

ClusterEventBus, SingleVMEventBus

public abstract class AbstractEventBus
extends java.lang.Object
implements EventBus

abstract class for common services of the system bus

Author:

Felix Jost

Constructor Summary

AbstractEventBus()

Method Summary

void	deregisterFor(GenericEventListener gel, OLATResourceable ores) deregisters/removes a GenericEventListener to listen to events concerning the OLATResourceable ores
abstract void	fireEventToListenersOf(MultiUserEvent event, OLATResourceable ores) fires an event to all listeners interested in events concerning this OLATResourceable ores.
abstract int	getListeningIdentityCntFor(OLATResourceable ores) Note for cluster: this method is cluster-safe.
java.util.Set	getListeningIdentityNamesFor(OLATResourceable ores) returns a Set of Identities which had at the very moment controllers which were listening to the OLATResourceable ores.
java.util.Map<java.lang.String,org.olat.core.util.event.EventAgency>	getUnmodifiableInfoCenter() used only for monitoring purposes
void	registerFor(GenericEventListener gel, Identity identity, OLATResourceable ores) registers a GenericEventListener to listen to events concerning the OLATResourceable ores
java.lang.String	toString()

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

AbstractEventBus

public AbstractEventBus()

Method Detail

registerFor

public void registerFor(GenericEventListener gel,
                        Identity identity,
                        OLATResourceable ores)

Description copied from interface: EventBus

registers a GenericEventListener to listen to events concerning the OLATResourceable ores

Specified by:

registerFor in interface EventBus

Parameters:

gel - the GenericEventListener / the class implementing it

identity - the identity to whicinfoh the listening (controller) belongs, or null if that is not known or the olat-system itself.

ores - the OLATResourceable

deregisterFor

public void deregisterFor(GenericEventListener gel,
                          OLATResourceable ores)

Description copied from interface: EventBus

deregisters/removes a GenericEventListener to listen to events concerning the OLATResourceable ores

Specified by:

deregisterFor in interface EventBus

getListeningIdentityNamesFor

public java.util.Set getListeningIdentityNamesFor(OLATResourceable ores)

Description copied from interface: EventBus

returns a Set of Identities which had at the very moment controllers which were listening to the OLATResourceable ores. Useful to e.g. warn a power-user which wants to delete a resource (e.g. a course) that there are users using this resource right at this time. NOTE: please use only for OLAT admin tools in order to protect the privacy of users. If you would like to say "the resource you want to delete is currently used by 10 users", but not say which users, then please use method getListeningIdentityCntFor(OLATResourceable ores)..
Note for cluster: this method returns only the names of listeners within one node/vm. However, the cnt of listeners is broadcasted amongst cluster nodes - see getListeningIdentityCntFor(OLATResourceable ores);

Specified by:

getListeningIdentityNamesFor in interface EventBus

Parameters:

ores - the OLATResourceable

Returns:

the listening names on a resource - only use for admin purposes!

getListeningIdentityCntFor

public abstract int getListeningIdentityCntFor(OLATResourceable ores)

Description copied from interface: EventBus

Note for cluster: this method is cluster-safe. in a cluster, it takes the latest counts received from all cluster nodes and sums them up.

Specified by:

getListeningIdentityCntFor in interface EventBus

Parameters:

ores - the resourceable

Returns:

the number of people currently using this resource

fireEventToListenersOf

public abstract void fireEventToListenersOf(MultiUserEvent event,
                                            OLATResourceable ores)

Description copied from interface: EventBus

fires an event to all listeners interested in events concerning this OLATResourceable ores. The events may be fired and received synchronously or asynchronously, depending on the concrete implementation.

Specified by:

fireEventToListenersOf in interface EventBus

Parameters:

event - the OLATResourceableEvent (must be serializable!, for multiple server olat installations)

ores - the OLATResourceable

getUnmodifiableInfoCenter

public java.util.Map<java.lang.String,org.olat.core.util.event.EventAgency> getUnmodifiableInfoCenter()

used only for monitoring purposes

Specified by:

getUnmodifiableInfoCenter in interface EventBus

Returns:

the whole infocenter map

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object