gcs
Class GcsMessageListener

java.lang.Object
  gcs.GcsMessageListener

All Implemented Interfaces:

GcsAdvancedMessageListener

Direct Known Subclasses:

SpreadGcsMessageListener

public abstract class GcsMessageListener
extends java.lang.Object
implements GcsAdvancedMessageListener

GcsMessageListener object allows blocking reception of messages through the listener message reception system. It is accomplished by calling getNewMessages() method. It activates the listener and blocks until at least one message is available or stopListener() is called. Upon new message arrival the listener is deactivated and message retrieved by the client.

Author:

tkob

Field Summary

protected boolean	active
protected ProfileEntity	mySessionReference
protected java.util.List<GcsMessage>	newMessages
protected boolean	quitting

Constructor Summary

protected

GcsMessageListener(ProfileEntity mySessionReference) Constructor.

Method Summary

protected abstract void	activateListener() Sets up the listener from the connection.
protected abstract void	deactivateListener() Removes the listener from the connection.
abstract java.util.List<GcsMessage>	getNewMessages() Used for retrieving new messages.
abstract boolean	isActive() Used to check the state of the GcsMessageListener.
abstract void	stopListener() Deactivates the listener and causes the getNewMessages() to continue when it is blocked.

Methods inherited from class java.lang.Object

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

Methods inherited from interface gcs.GcsAdvancedMessageListener

membershipMessageReceived, regularMessageReceived

Field Detail

mySessionReference

protected ProfileEntity mySessionReference

newMessages

protected java.util.List<GcsMessage> newMessages

quitting

protected boolean quitting

active

protected boolean active

Constructor Detail

GcsMessageListener

protected GcsMessageListener(ProfileEntity mySessionReference)

Constructor. The ProfileEntity reference given by the argument is used for retrieving the GcsConnection necessary for the listener to be set up or later removed.

Parameters:

mySessionReference -

Method Detail

activateListener

protected abstract void activateListener()
                                  throws GcsException

Sets up the listener from the connection.

Throws:

GcsException - if the listener can not be set up

deactivateListener

protected abstract void deactivateListener()
                                    throws GcsException

Removes the listener from the connection.

Throws:

GcsException

getNewMessages

public abstract java.util.List<GcsMessage> getNewMessages()
                                                   throws GcsException

Used for retrieving new messages. It returns when at least one message is avaliable or the stopListener() is called.

Returns:

list of new messages

Throws:

GcsException - if problem were encountered during reception of the messages

stopListener

public abstract void stopListener()
                           throws GcsException

Deactivates the listener and causes the getNewMessages() to continue when it is blocked.

Throws:

GcsException - if listener could not be deactivated

isActive

public abstract boolean isActive()

Used to check the state of the GcsMessageListener.

Returns:

true if the listener is set up, false otherwise