Package org.cometd.oort

Class Seti

java.lang.Object

org.eclipse.jetty.util.component.AbstractLifeCycle

org.cometd.oort.Seti

All Implemented Interfaces:

org.eclipse.jetty.util.component.Dumpable, org.eclipse.jetty.util.component.LifeCycle

@ManagedObject("CometD cloud peer discovery component")
public class Seti
extends org.eclipse.jetty.util.component.AbstractLifeCycle
implements org.eclipse.jetty.util.component.Dumpable

The component that Searches for Extra Terrestrial Intelligence or, in this case, just searches for a user logged onto a comet in an Oort cloud.

Seti allows an application to maintain a mapping from userId (any application identifier such as user names or database IDs that represent users) to server sessions using the associate(String, ServerSession) and disassociate(String, ServerSession) methods.

A typical example of usage of associate(String, ServerSession) is in a SecurityPolicy after a successful handshake (where authentication information can be linked with the server session), or in CometD services where the association is established upon receiving a message on a particular channel processed by the service itself.

Each comet in the cluster keeps its own mapping for clients connected to it.

The sendMessage(Collection, String, Object) and sendMessage(String, String, Object) methods may be used to send messages to user(s) anywhere in the Oort cluster and Seti organizes the search in order to locate the user(s).

See Also:

• SetiServlet

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
protected class	Seti.LocalLocation	A Location that represent a user connected to a local comet.
protected static interface	Seti.Location	The representation of where a user is.
static interface	Seti.PresenceListener	Listener interface that gets notified of remote Seti presence events.
protected class	Seti.SetiLocation	A Location that represent a user connected to a remote comet.

Nested classes/interfaces inherited from class org.eclipse.jetty.util.component.AbstractLifeCycle

org.eclipse.jetty.util.component.AbstractLifeCycle.AbstractLifeCycleListener, org.eclipse.jetty.util.component.AbstractLifeCycle.StopException

Nested classes/interfaces inherited from interface org.eclipse.jetty.util.component.Dumpable

org.eclipse.jetty.util.component.Dumpable.DumpableContainer

Nested classes/interfaces inherited from interface org.eclipse.jetty.util.component.LifeCycle

org.eclipse.jetty.util.component.LifeCycle.Listener

Field Summary

Fields

Modifier and Type	Field	Description
static final String	SETI_ATTRIBUTE

Fields inherited from class org.eclipse.jetty.util.component.AbstractLifeCycle

FAILED, STARTED, STARTING, STOPPED, STOPPING

Fields inherited from interface org.eclipse.jetty.util.component.Dumpable

KEY

Constructor Summary

Constructors

Constructor	Description
Seti(Oort oort)

Method Summary

Modifier and Type	Method	Description
void	addPresenceListener(Seti.PresenceListener listener)
boolean	associate(String userId, ServerSession session)	Associates the given userId to the given session.
protected boolean	associate(String userId, Seti.Location location)
Set<ServerSession>	disassociate(String userId)	Disassociates the given userId from all sessions.
boolean	disassociate(String userId, ServerSession session)	Disassociates the given userId from the given session.
protected boolean	disassociate(String userId, Seti.Location location)
protected void	doStart()
protected void	doStop()
void	dump(Appendable out, String indent)
protected String	generateSetiChannel(String setiId)
protected String	generateSetiId(String oortURL)
Set<String>	getAssociatedUserIds()
int	getAssociationCount(String userId)
String	getId()
Oort	getOort()
int	getPresenceCount(String userId)
Set<String>	getUserIds()
boolean	isAssociated(String userId)
boolean	isPresent(String userId)
protected void	protectSetiChannels(BayeuxServer bayeux)
protected void	receiveBroadcast(Message message)	Receives messages broadcast by other Setis in the cloud.
protected void	receiveDirect(Message message)	Receives messages directly from other Setis in the cloud, containing messages to be delivered to sessions connected to this comet.
protected void	receiveLocalPresence(Map<String,Object> presence)
protected void	receiveMessage(Map<String,Object> message)	Receives a seti message.
protected void	receivePresence(Map<String,Object> presence)	Receives a presence message.
protected void	receiveRemotePresence(Map<String,Object> presence)
protected void	removeAssociationsAndPresences()
void	removePresenceListener(Seti.PresenceListener listener)
void	removePresenceListeners()
protected void	removePresences(String oortURL)
void	sendMessage(String toUserId, String toChannel, Object data)	Sends a message to the given userId in the Oort cloud.
void	sendMessage(Collection<String> toUserIds, String toChannel, Object data)	Sends a message to multiple userIds in the Oort cloud.
String	toString()
protected void	unprotectSetiChannels(BayeuxServer bayeux)

Methods inherited from class org.eclipse.jetty.util.component.AbstractLifeCycle

addEventListener, getEventListeners, getState, getState, isFailed, isRunning, isStarted, isStarting, isStopped, isStopping, removeEventListener, setEventListeners, start, stop

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.eclipse.jetty.util.component.Dumpable

dump, dumpSelf

Field Details

SETI_ATTRIBUTE

public static final String SETI_ATTRIBUTE

Constructor Details

Seti

public Seti(Oort oort)

Method Details

getOort

@ManagedAttribute(value="The Oort of this Seti",
                  readonly=true)
public Oort getOort()

getId

@ManagedAttribute(value="The unique ID of this Seti",
                  readonly=true)
public String getId()

doStart

protected void doStart()

Overrides:

doStart in class org.eclipse.jetty.util.component.AbstractLifeCycle

doStop

protected void doStop()

Overrides:

doStop in class org.eclipse.jetty.util.component.AbstractLifeCycle

protectSetiChannels

protected void protectSetiChannels(BayeuxServer bayeux)

unprotectSetiChannels

protected void unprotectSetiChannels(BayeuxServer bayeux)

generateSetiId

protected String generateSetiId(String oortURL)

generateSetiChannel

protected String generateSetiChannel(String setiId)

associate

public boolean associate(String userId,
 ServerSession session)

Associates the given userId to the given session.

If it is the first association for this userId, broadcasts this information on the Oort cloud, so that other comets will know that the given userId is on this comet.

Parameters:

userId - the user identifier to associate

session - the session to map the userId to

Returns:

true if the session has been associated, false if it was already associated

See Also:

• isAssociated(String)
• disassociate(String, ServerSession)

associate

protected boolean associate(String userId,
 Seti.Location location)

isAssociated

@ManagedOperation(value="Whether the given userId is associated locally",
                  impact="INFO")
public boolean isAssociated(@Name(value="userId",description="The userId to test for local association")
 String userId)

Parameters:

userId - the user identifier to test for association

Returns:

whether the given userId has been associated via associate(String, ServerSession)

See Also:

• associate(String, ServerSession)
• isPresent(String)
• getAssociationCount(String)

getAssociationCount

@ManagedOperation(value="The number of local associations for the given userId",
                  impact="INFO")
public int getAssociationCount(@Name(value="userId",description="The userId to test for local association count")
 String userId)

Parameters:

userId - the user identifier to test for association count

Returns:

the number of local associations

See Also:

• isAssociated(String)
• getPresenceCount(String)

isPresent

@ManagedOperation(value="Whether the given userId is present in the cloud",
                  impact="INFO")
public boolean isPresent(@Name(value="userId",description="The userId to test for presence in the cloud")
 String userId)

Parameters:

userId - the user identifier to test for presence

Returns:

whether the given userId is present on the cloud (and therefore has been associated either locally or remotely)

See Also:

• isAssociated(String)
• getPresenceCount(String)

getPresenceCount

@ManagedOperation(value="The number of local and remote associations for the given userId",
                  impact="INFO")
public int getPresenceCount(@Name(value="userId",description="The userId to test for presence count")
 String userId)

Parameters:

userId - the user identifier to test for presence count

Returns:

the number of associations (local or remote) on the cloud

See Also:

• isPresent(String)
• getAssociationCount(String)

disassociate

public boolean disassociate(String userId,
 ServerSession session)

Disassociates the given userId from the given session.

If this is the last disassociation for this userId, broadcasts this information on the Oort cloud, so that other comets will know that the given userId no longer is on this comet.

Parameters:

userId - the user identifier to disassociate

session - the session mapped to the userId

Returns:

true if the session has been disassociated, false if it was not associated

See Also:

• associate(String, ServerSession)

disassociate

public Set<ServerSession> disassociate(String userId)

Disassociates the given userId from all sessions.

If this user had sessions on this comet, broadcast this information on the Oort cloud, so that other comets will know that the given userId no longer is on this comet.

Parameters:

userId - the user identifier to disassociate

Returns:

set of sessions that were disassociated

See Also:

• associate(String, ServerSession)

disassociate

protected boolean disassociate(String userId,
 Seti.Location location)

removeAssociationsAndPresences

protected void removeAssociationsAndPresences()

removePresences

protected void removePresences(String oortURL)

getUserIds

@ManagedAttribute(value="The set of userIds known to this Seti",
                  readonly=true)
public Set<String> getUserIds()

Returns:

the set of userIds known to this Seti, both local and remote

getAssociatedUserIds

public Set<String> getAssociatedUserIds()

Returns:

the set of userIds associated via associate(String, ServerSession)

sendMessage

public void sendMessage(String toUserId,
 String toChannel,
 Object data)

Sends a message to the given userId in the Oort cloud.

Parameters:

toUserId - the userId to send the message to

toChannel - the channel to send the message to

data - the content of the message

See Also:

• sendMessage(Collection, String, Object)

sendMessage

public void sendMessage(Collection<String> toUserIds,
 String toChannel,
 Object data)

Sends a message to multiple userIds in the Oort cloud.

Parameters:

toUserIds - the userIds to send the message to

toChannel - the channel to send the message to

data - the content of the message

receiveDirect

protected void receiveDirect(Message message)

Receives messages directly from other Setis in the cloud, containing messages to be delivered to sessions connected to this comet.

Parameters:

message - the message to deliver to a session connected to this comet

receiveBroadcast

protected void receiveBroadcast(Message message)

Receives messages broadcast by other Setis in the cloud.

Broadcast messages may be presence messages, where another Seti advertises an association, or fallback messages. Fallback messages are messages that were sent to a particular Seti because the sender thought the target userId was there, but the receiving Seti does not know that userId anymore (for example, it just disconnected); in this case, the receiving Seti broadcasts the message to the whole cloud, in the hope that the user can be found in some other comet of the cloud.

Parameters:

message - the message to possibly deliver to a session connected to this comet

receivePresence

protected void receivePresence(Map<String,Object> presence)

Receives a presence message.

Parameters:

presence - the presence message received

receiveLocalPresence

protected void receiveLocalPresence(Map<String,Object> presence)

receiveRemotePresence

protected void receiveRemotePresence(Map<String,Object> presence)

addPresenceListener

public void addPresenceListener(Seti.PresenceListener listener)

removePresenceListener

public void removePresenceListener(Seti.PresenceListener listener)

removePresenceListeners

public void removePresenceListeners()

receiveMessage

protected void receiveMessage(Map<String,Object> message)

Receives a seti message.

Parameters:

message - the seti message received

dump

public void dump(Appendable out,
 String indent)
          throws IOException

Specified by:

dump in interface org.eclipse.jetty.util.component.Dumpable

Throws:

IOException

toString

public String toString()

Overrides:

toString in class org.eclipse.jetty.util.component.AbstractLifeCycle