Package com.bea.httppubsub

Interface Channel

public interface Channel

Channel represents a pub/sub channel. A channel can have sub channels beneath it like a hierarchical structure.

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static class	Channel.ChannelPattern	This enum provides constants of the three channel patterns that are described in section 2.2.1 Channel Globbing of the Bayeux Protocol.

Method Summary

Modifier and Type	Method	Description
void	addSubChannel(Channel child)	Add one immediate child channel to this channel.
void	destroy(Client client)	Destroy this channel and all subchannels beneath it
java.util.List<Channel>	getAllSubChannels()	Return the list of all child channels for the current channel.
java.util.List<Client>	getClients(Channel.ChannelPattern pattern)	Return list of clients subscribed this channel or its children, depending on pattern parameter passed in.
java.lang.String	getName()	Return channel name defined in Bayeux protcol:
Channel	getParentChannel()	Return current channel's parent or null if current channel is root.
java.util.List<Channel>	getSubChannels()	Return the list of immediate child channels for the current channel.
void	publish(Client client, BayeuxMessage message, Channel.ChannelPattern pattern)	Publish to this channel or its child channels with specified pattern.
void	removeSubChannel(Channel child)	Remove sub channel from this channel.
void	subscribe(Client client)	Subscribe to this channel.
void	subscribe(Client client, Channel.ChannelPattern pattern)	Subscribe to this channel or its child channels with specified pattern.
void	unsubscribe(Client client)	Unsubscribe from all of this channel.
void	unsubscribe(Client client, Channel.ChannelPattern pattern)	Unsubscribe from this channel.

Method Detail

getName

java.lang.String getName()

Return channel name defined in Bayeux protcol:

  
   channel_name     = "/"  channel_segments
   channel_segments = channel_segment *( "/" channel_segment )
   channel_segment  = token 
 

Returns:

channel name.

getParentChannel

Channel getParentChannel()

Return current channel's parent or null if current channel is root.

Returns:

parent channel

getSubChannels

java.util.List<Channel> getSubChannels()

Return the list of immediate child channels for the current channel.

Returns:

the list of immediate child channels

getAllSubChannels

java.util.List<Channel> getAllSubChannels()

Return the list of all child channels for the current channel.

Returns:

the list of all child channels

addSubChannel

void addSubChannel(Channel child)

Add one immediate child channel to this channel.

Parameters:

child - child channel.

removeSubChannel

void removeSubChannel(Channel child)

Remove sub channel from this channel.

Parameters:

child - child channel.

destroy

void destroy(Client client)

Destroy this channel and all subchannels beneath it

Parameters:

client - Client object.

getClients

java.util.List<Client> getClients(Channel.ChannelPattern pattern)

Return list of clients subscribed this channel or its children, depending on pattern parameter passed in.

Parameters:

pattern - subscribe pattern, valid values are ITSELF, IMMEDIATE_SUBCHANNELS, ALL_SUBCHANNELS

Returns:

a list of client subscribing to this channel, or this channel's immediate child channels, or this channel's child channels.

subscribe

void subscribe(Client client)
        throws PubSubSecurityException

Subscribe to this channel.

 This method is equivalent to:
     subscribe(client, ChannelPattern.ITSELF);
 

Parameters:

client - client object.

Throws:

PubSubSecurityException - when any security error occurs.

subscribe

void subscribe(Client client,
               Channel.ChannelPattern pattern)
        throws PubSubSecurityException

Subscribe to this channel or its child channels with specified pattern.

• If client is interested in current channel only (/current_channel), the passed-in pattern should be ITSELF.
• If client is interested in current channel's immediate children ( /current_channel/*), the passed-in pattern should be IMMEDIATE_SUBCHANNELS
• If client is interested in all children of current channel ( /current_channel/**), the passed-in pattern should be ALL_SUBCHANNELS

Parameters:

client - client to subscribe this channel

pattern - pattern deciding which channels beneath the current channel should be subscribed.

Throws:

PubSubSecurityException - If security permission checking failure.

unsubscribe

void unsubscribe(Client client)

Unsubscribe from all of this channel.

 This method is equivalent to:
     unsubscribe(client, ChannelPattern.ITSELF);
     unsubscribe(client, ChannelPattern.IMMEDIATE_SUBCHANNELS);
     unsubscribe(client, ChannelPattern.ALL_SUBCHANNELS);
 

Parameters:

client - client object.

unsubscribe

void unsubscribe(Client client,
                 Channel.ChannelPattern pattern)

Unsubscribe from this channel.

• If client is interested in current channel only (/current_channel), the passed-in pattern should be ITSELF.
• If client is interested in current channel's immediate children ( /current_channel/*), the passed-in pattern should be IMMEDIATE_SUBCHANNELS
• If client is interested in all children of current channel ( /current_channel/**), the passed-in pattern should be ALL_SUBCHANNELS

Parameters:

client - client to unsubscribe this channel

pattern - pattern deciding which channels beneath the current channel should be unsubscribed.

publish

void publish(Client client,
             BayeuxMessage message,
             Channel.ChannelPattern pattern)
      throws PubSubSecurityException

Publish to this channel or its child channels with specified pattern.

• If client wants to publish messages to the current channel only, the passed-in pattern should be ITSELF.
• If client wants to publish messages to the current channel's immediate children, the passed-in pattern should be IMMEDIATE_SUBCHANNELS
• If client wants to publish messages to all child channels of the current channel, the passed-in pattern should be ALL_SUBCHANNELS

Parameters:

client - Client to publish to this channel

message - BayeuxMessage to publish

pattern - channel pattern to decide where to publish

Throws:

PubSubSecurityException - If no permission to publish