Rio Project 4.2 API Documentation

org.rioproject.event
Class RoundRobinEventHandler

java.lang.Object
  org.rioproject.event.EventHandler
      org.rioproject.event.RoundRobinEventHandler

public class RoundRobinEventHandler
extends EventHandler

The RoundRobinEventHandler provides an implementation of an EventHandler which supports the notification of events using round-robin semantic. This event handler will send notification of an event to a valid remote event listener (one that has an active lease) is the collection of event registrants. For each subsequent notification the next listener in the list will be notified.

If remote event listeners are removed from the collection of event registrants and the notification ordinal references the removed registrant, then the notification ordinal will reference the next registrant in the collection.

The sequence number for events is incremented after each subsequent fire invocation.

Author:

Dennis Reedy

Nested Class Summary

Nested classes/interfaces inherited from class org.rioproject.event.EventHandler

EventHandler.EventRegistrationResource

Field Summary

Fields inherited from class org.rioproject.event.EventHandler

descriptor, ektime, landlord, resourceMgr, RESPONSE_WATCH, responseWatch, sendTime, sent, sequenceNumber, sktime, step, t0, t1, tmp, watchRegistry

Constructor Summary

RoundRobinEventHandler(EventDescriptor descriptor)
Construct a RoundRobinEventHandler with an EventDescriptor and default lease maximum and time allocation

RoundRobinEventHandler(EventDescriptor descriptor, Configuration config)
Construct a RoundRobinEventHandler with an EventDescriptor and a Configuration object

Method Summary

void	fire(RemoteServiceEvent event) Implement the fire method from EventHandler.

Methods inherited from class org.rioproject.event.EventHandler

createWatch, destroyWatch, getNextServiceResource, getRegistrantCount, getWatch, printStats, register, terminate

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

RoundRobinEventHandler

public RoundRobinEventHandler(EventDescriptor descriptor)
                       throws Exception

Construct a RoundRobinEventHandler with an EventDescriptor and default lease maximum and time allocation

Parameters:

descriptor - The EventDescriptor

Throws:

Exception - If a landlord lease manager cannot be created

RoundRobinEventHandler

public RoundRobinEventHandler(EventDescriptor descriptor,
                              Configuration config)
                       throws Exception

Construct a RoundRobinEventHandler with an EventDescriptor and a Configuration object

Parameters:

descriptor - The EventDescriptor

config - The configuration object

Throws:

Exception - If a landlord lease manager cannot be created

Method Detail

fire

public void fire(RemoteServiceEvent event)
          throws NoEventConsumerException

Implement the fire method from EventHandler. This method will get the next available listener and send it an event. If there are no event registrants a NoEventConsumerException is thrown

Specified by:

fire in class EventHandler

Parameters:

event - The event to send

Throws:

NoEventConsumerException - is there are no event registrants to send the event to