org.jivesoftware.openfire.disco

Class IQDiscoInfoHandler

java.lang.Object

org.jivesoftware.openfire.container.BasicModule

org.jivesoftware.openfire.handler.IQHandler

org.jivesoftware.openfire.disco.IQDiscoInfoHandler

All Implemented Interfaces:

ChannelHandler, ClusterEventListener, Module

public class IQDiscoInfoHandler
extends IQHandler
implements ClusterEventListener

IQDiscoInfoHandler is responsible for handling disco#info requests. This class holds a map with the main entities and the associated DiscoInfoProvider. We are considering the host of the recipient JIDs as main entities. It's the DiscoInfoProvider responsibility to provide information about the JID's name together with any possible requested node.

For example, let's have in the entities map the following entries: "localhost" and "conference.localhost". Associated with each entry we have different DiscoInfoProviders. Now we receive a disco#info request for the following JID: "room@conference.localhost" which is a disco request for a MUC room. So IQDiscoInfoHandler will look for the DiscoInfoProvider associated with the JID's host which in this case is "conference.localhost". Once we have located the provider we will delegate to the provider the responsibility to provide the info specific to the JID's name which in this case is "room". Among the information that a room could provide we could find its identity and the features it supports (e.g. 'muc_passwordprotected', 'muc_unmoderated', etc.). Finally, after we have collected all the information provided by the provider we will add it to the reply. On the other hand, if no provider was found or the provider has no information for the requested name/node then a not-found error will be returned.

Author:

Gaston Dombiak

Field Summary

Fields

Modifier and Type	Field and Description
static String	NAMESPACE_DISCO_INFO

Fields inherited from class org.jivesoftware.openfire.handler.IQHandler

deliverer, sessionManager

Constructor Summary

Constructors

Constructor and Description
IQDiscoInfoHandler()

Method Summary

Methods

Modifier and Type	Method and Description
void	addServerFeature(String namespace) Adds one specific feature to the information returned whenever a disco for information is made against the server.
IQHandlerInfo	getInfo() Returns the handler information to help generically handle IQ packets.
org.xmpp.packet.IQ	handleIQ(org.xmpp.packet.IQ packet) Handles the received IQ packet.
void	initialize(XMPPServer server) Initializes the basic module.
void	joinedCluster() Notification event indicating that this JVM is now part of a cluster.
void	joinedCluster(byte[] nodeID) Notification event indicating that another JVM is now part of a cluster.
void	leftCluster() Notification event indicating that this JVM is no longer part of the cluster.
void	leftCluster(byte[] nodeID) Notification event indicating that another JVM is no longer part of the cluster.
void	markedAsSeniorClusterMember() Notification event indicating that this JVM is now the senior cluster member.
protected void	removeProvider(String name) Removes the DiscoInfoProvider related to a given entity.
void	removeServerFeature(String namespace) Removes a feature from the information returned whenever a disco for information is made against the server.
void	removeServerNodeInfoProvider(String node) Removes the DiscoInfoProvider to use when a disco#info packet is sent to the server itself and the specified node.
protected void	setProvider(String name, DiscoInfoProvider provider) Sets that a given DiscoInfoProvider will provide information about a given entity.
void	setServerNodeInfoProvider(String node, DiscoInfoProvider provider) Sets the DiscoInfoProvider to use when a disco#info packet is sent to the server itself and the specified node.

Methods inherited from class org.jivesoftware.openfire.handler.IQHandler

process

Methods inherited from class org.jivesoftware.openfire.container.BasicModule

destroy, getName, start, stop

Methods inherited from class java.lang.Object

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

Field Detail

NAMESPACE_DISCO_INFO

public static final String NAMESPACE_DISCO_INFO

See Also:

Constant Field Values

Constructor Detail

IQDiscoInfoHandler

public IQDiscoInfoHandler()

Method Detail

getInfo

public IQHandlerInfo getInfo()

Description copied from class: IQHandler

Returns the handler information to help generically handle IQ packets. IQHandlers that aren't local server iq handlers (e.g. chatbots, transports, etc) return null.

Specified by:

getInfo in class IQHandler

Returns:

The IQHandlerInfo for this handler

handleIQ

public org.xmpp.packet.IQ handleIQ(org.xmpp.packet.IQ packet)

Description copied from class: IQHandler

Handles the received IQ packet.

Specified by:

handleIQ in class IQHandler

Parameters:

packet - the IQ packet to handle.

Returns:

the response to send back.

setServerNodeInfoProvider

public void setServerNodeInfoProvider(String node,
                             DiscoInfoProvider provider)

Sets the DiscoInfoProvider to use when a disco#info packet is sent to the server itself and the specified node. For instance, if node matches "http://jabber.org/protocol/offline" then a special DiscoInfoProvider should be use to return information about offline messages.

Parameters:

node - the node that the provider will handle.

provider - the DiscoInfoProvider that will handle disco#info packets sent with the specified node.

removeServerNodeInfoProvider

public void removeServerNodeInfoProvider(String node)

Removes the DiscoInfoProvider to use when a disco#info packet is sent to the server itself and the specified node.

Parameters:

node - the node that the provider was handling.

setProvider

protected void setProvider(String name,
               DiscoInfoProvider provider)

Sets that a given DiscoInfoProvider will provide information about a given entity. This message must be used when new modules (e.g. MUC) are implemented and need to provide information about them.

Parameters:

name - the name of the entity.

provider - the DiscoInfoProvider that will provide the entity's information.

removeProvider

protected void removeProvider(String name)

Removes the DiscoInfoProvider related to a given entity.

Parameters:

name - the name of the entity.

addServerFeature

public void addServerFeature(String namespace)

Adds one specific feature to the information returned whenever a disco for information is made against the server.

Parameters:

namespace - the namespace identifying the new server feature.

removeServerFeature

public void removeServerFeature(String namespace)

Removes a feature from the information returned whenever a disco for information is made against the server.

Parameters:

namespace - the namespace of the feature to be removed.

initialize

public void initialize(XMPPServer server)

Description copied from class: BasicModule

Initializes the basic module.

Inheriting classes that choose to override this method MUST call this initialize() method before accessing BasicModule resources.

Specified by:

initialize in interface Module

Overrides:

initialize in class IQHandler

Parameters:

server - the server hosting this module.

joinedCluster

public void joinedCluster()

Description copied from interface: ClusterEventListener

Notification event indicating that this JVM is now part of a cluster. At this point the XMPPServer.getNodeID() holds the new nodeID value.

When joining the cluster as the senior cluster member the ClusterEventListener.markedAsSeniorClusterMember() event will be sent right after this event.

At this point the CacheFactory holds clustered caches. That means that modifications to the caches will be reflected in the cluster. The clustered caches were just obtained from the cluster and no local cached data was automatically moved.

Specified by:

joinedCluster in interface ClusterEventListener

joinedCluster

public void joinedCluster(byte[] nodeID)

Description copied from interface: ClusterEventListener

Notification event indicating that another JVM is now part of a cluster.

At this point the CacheFactory of the new node holds clustered caches. That means that modifications to the caches of this JVM will be reflected in the cluster and in particular in the new node.

Specified by:

joinedCluster in interface ClusterEventListener

Parameters:

nodeID - ID of the node that joined the cluster.

leftCluster

public void leftCluster()

Description copied from interface: ClusterEventListener

Notification event indicating that this JVM is no longer part of the cluster. This could happen when disabling clustering support, removing the enterprise plugin that provides clustering support or connection to cluster got lost.

Moreover, if we were in a "split brain" scenario (ie. separated cluster islands) and the island were this JVM belonged was marked as "old" then all nodes of that island will get the left cluster event and joined cluster events. That means that caches will be reset and thus will need to be repopulated again with fresh data from this JVM. This also includes the case where this JVM was the senior cluster member and when the islands met again then this JVM stopped being the senior member.

At this point the CacheFactory holds local caches. That means that modifications to the caches will only affect this JVM.

Specified by:

leftCluster in interface ClusterEventListener

leftCluster

public void leftCluster(byte[] nodeID)

Description copied from interface: ClusterEventListener

Notification event indicating that another JVM is no longer part of the cluster. This could happen when disabling clustering support, removing the enterprise plugin that provides clustering support or connection to cluster got lost.

Moreover, if we were in a "split brain" scenario (ie. separated cluster islands) and the island were the other JVM belonged was marked as "old" then all nodes of that island will get the left cluster event and joined cluster events. That means that caches will be reset and thus will need to be repopulated again with fresh data from this JVM. This also includes the case where the other JVM was the senior cluster member and when the islands met again then the other JVM stopped being the senior member.

At this point the CacheFactory of the leaving node holds local caches. That means that modifications to the caches of this JVM will not affect the leaving node but other cluster members.

Specified by:

leftCluster in interface ClusterEventListener

Parameters:

nodeID - ID of the node that is left the cluster.

markedAsSeniorClusterMember

public void markedAsSeniorClusterMember()

Description copied from interface: ClusterEventListener

Notification event indicating that this JVM is now the senior cluster member. This could either happen when initially joining the cluster or when the senior cluster member node left the cluster and this JVM was marked as the new senior cluster member.

Moreover, in the case of a "split brain" scenario (ie. separated cluster islands) each island will have its own senior cluster member. However, when the islands meet again there could only be one senior cluster member so one of the senior cluster members will stop playing that role. When that happens the JVM no longer playing that role will receive the ClusterEventListener.leftCluster() and ClusterEventListener.joinedCluster() events.

Specified by:

markedAsSeniorClusterMember in interface ClusterEventListener