jgroup.relacs.gm
Class MulticastLayer

java.lang.Object
  jgroup.relacs.gm.MulticastLayer

All Implemented Interfaces:

Layer, MulticastService, EventTags, DispatcherListener

public final class MulticastLayer
extends java.lang.Object
implements MulticastService, DispatcherListener, EventTags

The MulticastLayer class implements the multicast service.

Since:

Jgroup 2.2

Author:

Alberto Montresor, Hein Meling

Nested Class Summary

Nested classes/interfaces inherited from interface jgroup.core.Layer

Layer.FinalizeLayer

Field Summary

Fields inherited from interface jgroup.relacs.events.EventTags

DAEMON_FAILURE_EVENT, DELIVERY_ACK, DELIVERY_EVENT, INSTALL_ACK, INSTALL_EVENT, JOIN_REQUEST, LEAVE_REQUEST, MEMBER_LEFT_EVENT, MULTICAST_REQUEST, PREPARE_ACK, PREPARE_EVENT

Method Summary

void	addListener(java.lang.Object listener) Add a listener object for this layer to provide upcalls to in response to multicast events.
int[]	eventTypes() Returns the set of event types supported by this listener.
static MulticastLayer	getLayer(DispatcherService ds, MembershipService pgms)
java.io.OutputStream	getMessage(java.lang.String protocol) Returns an output stream to be used to encode a message.
void	mcast(java.io.OutputStream stream, AckListener ackl) Multicast a message enclosed in the stream out to the members of the current view of the group.
void	mcast(java.io.OutputStream out, AckListener ackl, ChainIdentifier chId) Multicast a message enclosed in the stream out to the members of the current view of the group.
void	mcast(java.lang.String protocol, java.lang.Object obj, AckListener ackl) Multicast a serializable object to the members of the current view of a group.
void	notifyEvent(Event event) This method is invoked by a dispatcher to notify a listener about an event.

Methods inherited from class java.lang.Object

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

Method Detail

getLayer

public static MulticastLayer getLayer(DispatcherService ds,
                                      MembershipService pgms)
                               throws JgroupException

Throws:

JgroupException

addListener

public void addListener(java.lang.Object listener)

Add a listener object for this layer to provide upcalls to in response to multicast events.

Specified by:

addListener in interface Layer

Parameters:

listener - An Object representation of the listener interface. This will typically be cast to the appropriate listener interface type after checking the type with the instanceof operator.

mcast

public void mcast(java.io.OutputStream out,
                  AckListener ackl,
                  ChainIdentifier chId)
           throws JgroupException

Description copied from interface: MulticastService

Multicast a message enclosed in the stream out to the members of the current view of the group.

The invoker may specify an AckListener object, which will be notified when objects returned by members delivering this message, are received.

Specified by:

mcast in interface MulticastService

Parameters:

out - The stream message to be multicast.

ackl - Acknowledgement listener to be notified; if null, no listener will be notified.

chId - Identifier of a previous message (delivered through a deliverStream). This is only required for multicast messages that relate to some previous multicast message. It will only be used in extremely rare cases, to avoid that the membership service delays the message while running the agreement protocol, which would otherwise prevent the agreement protocol from concluding.

Throws:

JgroupException - Rasied if the group manager receives a request to multicast a message after having joined a group, but before having received the first view for it; or after having requested to leave the group.

mcast

public void mcast(java.io.OutputStream stream,
                  AckListener ackl)
           throws JgroupException

Description copied from interface: MulticastService

Multicast a message enclosed in the stream out to the members of the current view of the group.

The invoker may specify an AckListener object, which will be notified when objects returned by members delivering this message, are received.

Specified by:

mcast in interface MulticastService

Parameters:

stream - The stream message to be multicast.

ackl - Acknowledgement listener to be notified; if null, no listener will be notified.

Throws:

JgroupException - Rasied if the group manager receives a request to multicast a message after having joined a group, but before having received the first view for it; or after having requested to leave the group.

mcast

public void mcast(java.lang.String protocol,
                  java.lang.Object obj,
                  AckListener ackl)
           throws JgroupException,
                  java.io.IOException

Description copied from interface: MulticastService

Multicast a serializable object to the members of the current view of a group.

The invoker may specify an AckListener object, which will be notified when objects returned by members delivering this message are received.

Specified by:

mcast in interface MulticastService

Parameters:

protocol - The protocol for the message object to be multicast.

obj - The message object to be multicast.

ackl - Acknowledgement listener to be notified; if null, no listener will be notified.

Throws:

JgroupException - Rasied if the group manager receives a request to multicast a message after having joined a group, but before having received the first view for it; or after having requested to leave the group.

java.io.IOException - Raised if the object to be multicast could not be serialized.

getMessage

public java.io.OutputStream getMessage(java.lang.String protocol)
                                throws java.io.IOException

Description copied from interface: MulticastService

Returns an output stream to be used to encode a message. Method mcast(OutputStream, AckListener) accepts only multicast messages obtained through this method. The provided output stream is a memory data structure optimized to avoid useless data copies.

Specified by:

getMessage in interface MulticastService

Parameters:

protocol - The protocol name used for the OutputStream message object to be multicast.

Throws:

java.io.IOException

eventTypes

public int[] eventTypes()

Description copied from interface: DispatcherListener

Returns the set of event types supported by this listener. Legal event types are given in the EventTags interface.

Specified by:

eventTypes in interface DispatcherListener

notifyEvent

public void notifyEvent(Event event)

Description copied from interface: DispatcherListener

This method is invoked by a dispatcher to notify a listener about an event.

Specified by:

notifyEvent in interface DispatcherListener

Parameters:

event - The Event object to be processed.