Package org.cometd.common

Class AbstractClientSession

java.lang.Object

org.cometd.common.AbstractClientSession

All Implemented Interfaces:

ClientSession, Session, org.eclipse.jetty.util.component.Dumpable

Direct Known Subclasses:

BayeuxClient, LocalSessionImpl

public abstract class AbstractClientSession
extends Object
implements ClientSession, org.eclipse.jetty.util.component.Dumpable

Partial implementation of ClientSession.

It handles extensions and batching, and provides utility methods to be used by subclasses.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
protected class	AbstractClientSession.AbstractSessionChannel	A channel scoped to a ClientSession.

Nested classes/interfaces inherited from interface org.cometd.bayeux.client.ClientSession

ClientSession.Extension, ClientSession.MessageListener

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	AbstractClientSession()

Method Summary

Modifier and Type	Method	Description
void	addExtension(ClientSession.Extension extension)	Adds an extension to this session.
void	batch(Runnable batch)	Executes the given command in a batch so that any Bayeux message sent by the command (via the Bayeux API) is queued up until the end of the command and then all messages are sent at once.
String	dump()
void	dump(Appendable out, String indent)
boolean	endBatch()	Ends a batch started with Session.startBatch().
protected boolean	extendRcv(Message.Mutable message)
protected boolean	extendSend(Message.Mutable message)
Object	getAttribute(String name)	Retrieves the value of named session attribute.
Set<String>	getAttributeNames()
ClientSessionChannel	getChannel(String channelName)	Returns a client side channel scoped by this session.
ClientSessionChannel	getChannel(ChannelId channelId)
protected ConcurrentMap<String,AbstractClientSession.AbstractSessionChannel>	getChannels()
List<ClientSession.Extension>	getExtensions()
protected boolean	isBatching()
protected abstract AbstractClientSession.AbstractSessionChannel	newChannel(ChannelId channelId)
protected abstract ChannelId	newChannelId(String channelId)
protected Message.Mutable	newMessage()
protected String	newMessageId()
protected void	notifyListener(ClientSessionChannel.MessageListener listener, Message.Mutable message)
protected void	notifyListeners(Message.Mutable message)
void	receive(Message.Mutable message)	Receives a message (from the server) and process it.
protected void	registerCallback(String messageId, ClientSessionChannel.MessageListener callback)
protected void	registerSubscriber(String messageId, ClientSessionChannel.MessageListener subscriber)
void	remoteCall(String target, Object data, ClientSession.MessageListener callback)	Performs a remote call to the server, to the specified target, and with the given data as payload.
Object	removeAttribute(String name)	Removes a named session attribute.
void	removeExtension(ClientSession.Extension extension)	Removes an extension from this session.
protected void	resetSubscriptions()
protected abstract void	send(Message.Mutable message)
protected abstract void	sendBatch()
void	setAttribute(String name, Object value)	Sets a named session attribute value.
void	startBatch()	Starts a batch, to be ended with Session.endBatch().
protected ClientSessionChannel.MessageListener	unregisterCallback(String messageId)
protected ClientSessionChannel.MessageListener	unregisterSubscriber(String messageId)

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.cometd.bayeux.client.ClientSession

disconnect, handshake, handshake, handshake

Methods inherited from interface org.cometd.bayeux.Session

disconnect, getId, isConnected, isHandshook

Constructor Details

AbstractClientSession

protected AbstractClientSession()

Method Details

newMessageId

protected String newMessageId()

addExtension

public void addExtension(ClientSession.Extension extension)

Description copied from interface: ClientSession

Adds an extension to this session.

Specified by:

addExtension in interface ClientSession

Parameters:

extension - the extension to add

See Also:

ClientSession.removeExtension(Extension)

removeExtension

public void removeExtension(ClientSession.Extension extension)

Description copied from interface: ClientSession

Removes an extension from this session.

Specified by:

removeExtension in interface ClientSession

Parameters:

extension - the extension to remove

See Also:

ClientSession.addExtension(Extension)

getExtensions

public List<ClientSession.Extension> getExtensions()

Specified by:

getExtensions in interface ClientSession

Returns:

an immutable list of extensions present in this ClientSession instance

See Also:

ClientSession.addExtension(Extension)

extendSend

protected boolean extendSend(Message.Mutable message)

extendRcv

protected boolean extendRcv(Message.Mutable message)

newChannelId

protected abstract ChannelId newChannelId(String channelId)

newChannel

protected abstract AbstractClientSession.AbstractSessionChannel newChannel(ChannelId channelId)

getChannel

public ClientSessionChannel getChannel(String channelName)

Description copied from interface: ClientSession

Returns a client side channel scoped by this session.

The channel name may be for a specific channel (e.g. "/foo/bar") or for a wild channel (e.g. "/meta/**" or "/foo/*").

This method will always return a channel, even if the the channel has not been created on the server side. The server side channel is only involved once a publish or subscribe method is called on the channel returned by this method.

Typical usage examples are:

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

Specified by:

getChannel in interface ClientSession

Parameters:

channelName - specific or wild channel name.

Returns:

a channel scoped by this session.

getChannel

public ClientSessionChannel getChannel(ChannelId channelId)

getChannels

protected ConcurrentMap<String,AbstractClientSession.AbstractSessionChannel> getChannels()

startBatch

public void startBatch()

Description copied from interface: Session

Starts a batch, to be ended with Session.endBatch().

The Session.batch(Runnable) method should be preferred since it automatically starts and ends a batch without relying on a try/finally block.

This method is to be used in the cases where the use of Session.batch(Runnable) is not possible or would make the code more complex.

Specified by:

startBatch in interface Session

See Also:

Session.endBatch(), Session.batch(Runnable)

sendBatch

protected abstract void sendBatch()

endBatch

public boolean endBatch()

Description copied from interface: Session

Ends a batch started with Session.startBatch().

Specified by:

endBatch in interface Session

Returns:

true if the batch ended and there were messages to send.

See Also:

Session.startBatch()

batch

public void batch(Runnable batch)

Description copied from interface: Session

Executes the given command in a batch so that any Bayeux message sent by the command (via the Bayeux API) is queued up until the end of the command and then all messages are sent at once.

Specified by:

batch in interface Session

Parameters:

batch - the Runnable to run as a batch

isBatching

protected boolean isBatching()

getAttribute

public Object getAttribute(String name)

Description copied from interface: Session

Retrieves the value of named session attribute.

Specified by:

getAttribute in interface Session

Parameters:

name - the name of the attribute

Returns:

the attribute value or null if the attribute is not present

getAttributeNames

public Set<String> getAttributeNames()

Specified by:

getAttributeNames in interface Session

Returns:

the list of session attribute names.

removeAttribute

public Object removeAttribute(String name)

Description copied from interface: Session

Removes a named session attribute.

Specified by:

removeAttribute in interface Session

Parameters:

name - the name of the attribute

Returns:

the value of the attribute

setAttribute

public void setAttribute(String name, Object value)

Description copied from interface: Session

Sets a named session attribute value.

Session attributes are convenience data that allows arbitrary application data to be associated with a session.

Specified by:

setAttribute in interface Session

Parameters:

name - the attribute name

value - the attribute value

remoteCall

public void remoteCall(String target, Object data, ClientSession.MessageListener callback)

Description copied from interface: ClientSession

Performs a remote call to the server, to the specified target, and with the given data as payload.

The remote call response will be delivered via the callback parameter.

Typical usage:

 clientSession.remoteCall("getOnlineStatus", userId, new MessageListener()
 {
     @Override
     public void onMessage(Message message)
     {
         if (message.isSuccessful())
         {
             String status = (String)message.getData();
             // Update UI with online status.
         }
         else
         {
             // Remote call failed.
         }
     }
 });
 

Specified by:

remoteCall in interface ClientSession

Parameters:

target - the remote call target

data - the remote call parameters

callback - the listener that receives the remote call response

send

protected abstract void send(Message.Mutable message)

newMessage

protected Message.Mutable newMessage()

resetSubscriptions

protected void resetSubscriptions()

receive

public void receive(Message.Mutable message)

Receives a message (from the server) and process it.

Processing the message involves calling the receive extensions and the channel listeners.

Parameters:

message - the message received.

notifyListeners

protected void notifyListeners(Message.Mutable message)

notifyListener

protected void notifyListener(ClientSessionChannel.MessageListener listener, Message.Mutable message)

registerCallback

protected void registerCallback(String messageId, ClientSessionChannel.MessageListener callback)

unregisterCallback

protected ClientSessionChannel.MessageListener unregisterCallback(String messageId)

registerSubscriber

protected void registerSubscriber(String messageId, ClientSessionChannel.MessageListener subscriber)

unregisterSubscriber

protected ClientSessionChannel.MessageListener unregisterSubscriber(String messageId)

dump

public String dump()

Specified by:

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

dump

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

Specified by:

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

Throws:

IOException