org.hawkular.cmdgw.command.ws

Class WsSessions

java.lang.Object

org.hawkular.cmdgw.command.ws.WsSessions

public class WsSessions
extends Object

Maintains a map of websocket Sessions currently connected with the server. The choice of the key for the map is up to the caller.

A sessionId of a UI client's Session or a feed's feedId are the most prominent candidates for keys.

A thread safety note: this class uses a ReadWriteLock internally, hence its public methods can be safely called from multiple threads.

Author:

Peter Palaga

Constructor Summary

Constructors

Constructor and Description
WsSessions(String endpoint)

Method Summary

Modifier and Type	Method and Description
boolean	addSession(String key, javax.websocket.Session newSession) Stores the given newSession under the given key.
void	addWsSessionListenerProducer(BiFunction<String,javax.websocket.Session,WsSessionListener> wsSessionListenerProducer) Add the given wsSessionListenerProducers to the internal list of WsSessionListener producers.
void	destroy()
javax.websocket.Session	getSession(String key) Returns the Session stored under the given key or null if there is no such session.
void	removeSession(String key, javax.websocket.Session doomedSession) Removes the session associated with the given key.
void	removeWsSessionListenerProducer(BiFunction<String,javax.websocket.Session,WsSessionListener> wsSessionListenerProducer) Remove the given wsSessionListenerProducers from the internal list of WsSessionListener producers.

Methods inherited from class java.lang.Object

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

Constructor Detail

WsSessions

public WsSessions(String endpoint)

Method Detail

addSession

public boolean addSession(String key,
                          javax.websocket.Session newSession)

Stores the given newSession under the given key.

If there is already a session associated with the given key, the given newSession is closed; it is not added or associated with the given key and an error will be logged. The original session remains associated with the key.

When adding a session, that new session's websocket session listeners will be told via WsSessionListener.sessionAdded().

Parameters:

key - the key (feedId or sessionId) that will be associated with the new session

newSession - the new session to add

Returns:

true if the session was added; false otherwise.

addWsSessionListenerProducer

public void addWsSessionListenerProducer(BiFunction<String,javax.websocket.Session,WsSessionListener> wsSessionListenerProducer)

Add the given wsSessionListenerProducers to the internal list of WsSessionListener producers. A listener-producer is just a bi-function that takes a key string (like a UI client session ID or a feed ID) and a websocket Session and produces a websocket session listener. A websocket session listener has the job of performing tasks when a websocket client connects and disconnects (for example, when a websocket client connects and its websocket session is created, a websocket session listener will then need to add bus listeners so the websocket client's messages can be processed properly).

Parameters:

wsSessionListenerProducer - a function that produces WsSessionListener for a given pair of sessionKey and Session.

getSession

public javax.websocket.Session getSession(String key)

Returns the Session stored under the given key or null if there is no such session.

Parameters:

key - the key to look for

Returns:

the Session stored under the given key or null if there is no such session.

removeSession

public void removeSession(String key,
                          javax.websocket.Session doomedSession)

Removes the session associated with the given key. If doomedSession is not null, the session matching the given key in sessions will only be removed if that session has the same ID as the given doomedSession.

When removing a known session, that doomed session's websocket session listeners will be told via WsSessionListener.sessionRemoved().

Parameters:

key - identifies the session to be removed

doomedSession - if not null, ensures that only this session will be removed

destroy

public void destroy()

removeWsSessionListenerProducer

public void removeWsSessionListenerProducer(BiFunction<String,javax.websocket.Session,WsSessionListener> wsSessionListenerProducer)

Remove the given wsSessionListenerProducers from the internal list of WsSessionListener producers.

Parameters:

wsSessionListenerProducer - a function that produces WsSessionListener for a given pair of sessionKey and Session.