Package org.cometd.bayeux.client

Interface ClientSessionChannel

All Superinterfaces:

Channel

All Known Implementing Classes:

AbstractClientSession.AbstractSessionChannel, BayeuxClient.BayeuxClientChannel, LocalSessionImpl.LocalChannel

public interface ClientSessionChannel
extends Channel

A client side channel representation.

A ClientSessionChannel is scoped to a particular ClientSession that is obtained by a call to ClientSession.getChannel(String).

Typical usage examples are:

 clientSession.getChannel("/foo/bar").subscribe(mySubscriptionListener);
 clientSession.getChannel("/foo/bar").publish("Hello");
 clientSession.getChannel("/meta/*").addListener(myMetaChannelListener);
 

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static interface	ClientSessionChannel.ClientSessionChannelListener	Represents a listener on a ClientSessionChannel.
static interface	ClientSessionChannel.MessageListener	A listener for messages on a ClientSessionChannel.

Field Summary

Fields inherited from interface org.cometd.bayeux.Channel

META, META_CONNECT, META_DISCONNECT, META_HANDSHAKE, META_SUBSCRIBE, META_UNSUBSCRIBE, SERVICE

Method Summary

Modifier and Type	Method	Description
void	addListener(ClientSessionChannel.ClientSessionChannelListener listener)	Adds a listener to this channel.
List<ClientSessionChannel.ClientSessionChannelListener>	getListeners()
ClientSession	getSession()
List<ClientSessionChannel.MessageListener>	getSubscribers()
boolean	isReleased()
void	publish(Object data)	Publishes the given data onto this channel.
void	publish(Object data, ClientSessionChannel.MessageListener callback)	Publishes the given data onto this channel, notifying the given callback of the publish result, whether successful or unsuccessful.
void	publish(Message.Mutable message, ClientSessionChannel.MessageListener callback)	Publishes the given message onto this channel, notifying the given callback of the publish result.
boolean	release()	Releases this channel from its ClientSession.
void	removeListener(ClientSessionChannel.ClientSessionChannelListener listener)	Removes the given listener from this channel.
void	subscribe(ClientSessionChannel.MessageListener listener)	Equivalent to subscribe(listener, null).
void	subscribe(ClientSessionChannel.MessageListener listener, ClientSessionChannel.MessageListener callback)	Subscribes the given listener to receive messages sent to this channel.
void	unsubscribe()	Unsubscribes all subscribers registered on this channel.
void	unsubscribe(ClientSessionChannel.MessageListener listener)	Equivalent to unsubscribe(listener, null).
void	unsubscribe(ClientSessionChannel.MessageListener listener, ClientSessionChannel.MessageListener callback)	Unsubscribes the given listener from receiving messages sent to this channel.

Methods inherited from interface org.cometd.bayeux.Channel

getAttribute, getAttributeNames, getChannelId, getId, isBroadcast, isDeepWild, isMeta, isService, isWild, removeAttribute, setAttribute

Method Details

addListener

void addListener(ClientSessionChannel.ClientSessionChannelListener listener)

Adds a listener to this channel.

If the listener is a ClientSessionChannel.MessageListener, it will be invoked if a message arrives to this channel.

Adding a listener never involves communication with the server, differently from subscribe(MessageListener).

Listeners are best suited to receive messages from meta channels.

Parameters:

listener - the listener to add

See Also:

removeListener(ClientSessionChannelListener)

removeListener

void removeListener(ClientSessionChannel.ClientSessionChannelListener listener)

Removes the given listener from this channel.

Removing a listener never involves communication with the server, differently from unsubscribe(MessageListener).

Parameters:

listener - the listener to remove

See Also:

addListener(ClientSessionChannelListener)

getListeners

List<ClientSessionChannel.ClientSessionChannelListener> getListeners()

Returns:

an immutable snapshot of the listeners

See Also:

addListener(ClientSessionChannelListener)

getSession

ClientSession getSession()

Returns:

the client session associated with this channel

publish

void publish(Object data)

Publishes the given data onto this channel.

The data published must not be null and can be any object that can be natively converted to JSON (numbers, strings, arrays, lists, maps), or objects for which a JSON converter has been registered with the infrastructure responsible of the JSON conversion.

Parameters:

data - the data to publish

See Also:

publish(Object, MessageListener)

publish

void publish(Object data, ClientSessionChannel.MessageListener callback)

Publishes the given data onto this channel, notifying the given callback of the publish result, whether successful or unsuccessful.

Parameters:

data - the data to publish

callback - the message callback to notify of the publish result

See Also:

publish(Object), publish(Message.Mutable, MessageListener)

publish

void publish(Message.Mutable message, ClientSessionChannel.MessageListener callback)

Publishes the given message onto this channel, notifying the given callback of the publish result.

Parameters:

message - the message to publish

callback - the message callback to notify of the publish result

See Also:

publish(Object, MessageListener)

subscribe

void subscribe(ClientSessionChannel.MessageListener listener)

Equivalent to subscribe(listener, null).

Parameters:

listener - the listener to register and invoke when a message arrives on this channel.

subscribe

void subscribe(ClientSessionChannel.MessageListener listener, ClientSessionChannel.MessageListener callback)

Subscribes the given listener to receive messages sent to this channel.

Subscription involves communication with the server only for the first listener subscribed to this channel. Listeners registered after the first will not cause a message being sent to the server.

The callback parameter will be invoked upon acknowledgment of the subscription by the server, and therefore only for the first subscription to this channel.

Parameters:

listener - the listener to register and invoke when a message arrives on this channel.

callback - the listener to notify of the subscribe result.

See Also:

unsubscribe(MessageListener), addListener(ClientSessionChannelListener)

unsubscribe

void unsubscribe(ClientSessionChannel.MessageListener listener)

Equivalent to unsubscribe(listener, null).

Parameters:

listener - the listener to unsubscribe

unsubscribe

void unsubscribe(ClientSessionChannel.MessageListener listener, ClientSessionChannel.MessageListener callback)

Unsubscribes the given listener from receiving messages sent to this channel.

Unsubscription involves communication with the server only for the last listener unsubscribed from this channel.

The callback parameter will be invoked upon acknowledgment of the unsubscription by the server, and therefore only for the last unsubscription from this channel.

Parameters:

listener - the listener to unsubscribe

callback - the listener to notify of the unsubscribe result.

See Also:

subscribe(MessageListener), unsubscribe()

unsubscribe

void unsubscribe()

Unsubscribes all subscribers registered on this channel.

See Also:

subscribe(MessageListener)

getSubscribers

List<ClientSessionChannel.MessageListener> getSubscribers()

Returns:

an immutable snapshot of the subscribers

See Also:

subscribe(MessageListener)

release

boolean release()

Releases this channel from its ClientSession.

If the release is successful, subsequent invocations of ClientSession.getChannel(String) will return a new, different, instance of a ClientSessionChannel.

The release of a ClientSessionChannel is successful only if no listeners and no subscribers are present at the moment of the release.

Returns:

true if the release was successful, false otherwise

See Also:

isReleased()

isReleased

boolean isReleased()

Returns:

whether this channel has been released

See Also:

release()