ch.bind.philib.msg

Interface PubSub

All Known Implementing Classes:

PubSubVM

public interface PubSub

Method Summary

Methods

Modifier and Type	Method and Description
Map<String,Integer>	activeChannels() Lists all channels with one or more subscriptions. The returned Map is a representation of the state at the time of the invocation of this method.
void	publish(String channelName, Object message) Asynchronously published a message to all subscribers of a channel.
Subscription	subscribe(String channelName, MessageHandler handler) subscribe a MessageHandler to a channel.

Method Detail

subscribe

Subscription subscribe(String channelName,
                     MessageHandler handler)

subscribe a MessageHandler to a channel.

Parameters:

channelName -

handler - a non-null handler

Returns:

an Subscription object if this is a new message handler, null otherwise.

Throws:

IllegalArgumentException - if the channelName parameter is null or empty or if the handler parameter is null.

publish

void publish(String channelName,
           Object message)

Asynchronously published a message to all subscribers of a channel.

Parameters:

channelName -

message - the non-null message to be sent

Throws:

IllegalArgumentException - if the channelName parameter is null or empty or if the message parameter is null.

activeChannels

Map<String,Integer> activeChannels()

Lists all channels with one or more subscriptions.
The returned Map is a representation of the state at the time of the invocation of this method. New subscriptions or cancelled subscriptions which happen after the invocation of this method will not be reflected in maps of previous queries.

Returns:

a Map with active channel names as key and the number of subscribers as value.