org.xmlBlaster.jms
Class XBMessageConsumer

java.lang.Object
  org.xmlBlaster.jms.XBMessageConsumer

All Implemented Interfaces:

javax.jms.MessageConsumer, I_Callback

Direct Known Subclasses:

XBQueueReceiver, XBTopicSubscriber

public class XBMessageConsumer
extends java.lang.Object
implements javax.jms.MessageConsumer, I_Callback

XBMessageConsumer

Author:

Michele Laghi

Field Summary

protected javax.jms.Destination	destination
protected javax.jms.ExceptionListener	exceptionListener
protected Global	global
private static java.util.logging.Logger	log
private java.lang.String	ME
protected javax.jms.Message	msg
protected javax.jms.MessageListener	msgListener
protected java.lang.String	msgSelector
protected boolean	noLocal
protected boolean	open
protected XBSession	session
protected SubscribeReturnQos	subscribeReturnQos

Constructor Summary

XBMessageConsumer(XBSession session, javax.jms.Destination destination, java.lang.String msgSelector, boolean noLocal)
For each consumer created, an own xmlBlaster subscription is done since the msgSelector (i.e.

Method Summary

protected void	checkIfOpen(java.lang.String methodName)
void	close() unsubscribe here
javax.jms.MessageListener	getMessageListener()
java.lang.String	getMessageSelector()
private java.lang.String	getOid(javax.jms.Destination destination)
javax.jms.Message	receive()
javax.jms.Message	receive(long delay)
javax.jms.Message	receiveNoWait() Currently the implementation is such that if no msgListener has been associated to this consumer, the onMessage blocks until receiveNoWait has been invoked (if there is a message pending).
void	setMessageListener(javax.jms.MessageListener msgListener)
private SubscribeReturnQos	subscribe(javax.jms.Destination destination, java.lang.String msgSelector, boolean noLocal)
java.lang.String	update(java.lang.String cbSessionId, UpdateKey updateKey, byte[] content, UpdateQos updateQos) This is the callback method invoked from I_XmlBlasterAccess informing the client in an asynchronous mode about a new message.

Methods inherited from class java.lang.Object

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

Field Detail

ME

private java.lang.String ME

global

protected Global global

log

private static java.util.logging.Logger log

msgSelector

protected java.lang.String msgSelector

msgListener

protected javax.jms.MessageListener msgListener

session

protected XBSession session

msg

protected javax.jms.Message msg

subscribeReturnQos

protected SubscribeReturnQos subscribeReturnQos

destination

protected javax.jms.Destination destination

noLocal

protected boolean noLocal

exceptionListener

protected javax.jms.ExceptionListener exceptionListener

open

protected boolean open

Constructor Detail

XBMessageConsumer

XBMessageConsumer(XBSession session,
                  javax.jms.Destination destination,
                  java.lang.String msgSelector,
                  boolean noLocal)
            throws javax.jms.JMSException

For each consumer created, an own xmlBlaster subscription is done since the msgSelector (i.e. in xmlBlaster the mime plugin) could be different from one consumer to another. This is done in the constructor of the MessageConsumer. The msgSelector can be null.

Throws:

javax.jms.JMSException

Method Detail

checkIfOpen

protected final void checkIfOpen(java.lang.String methodName)
                          throws javax.jms.JMSException

Throws:

javax.jms.JMSException

getOid

private final java.lang.String getOid(javax.jms.Destination destination)
                               throws javax.jms.JMSException

Throws:

javax.jms.JMSException

subscribe

private final SubscribeReturnQos subscribe(javax.jms.Destination destination,
                                           java.lang.String msgSelector,
                                           boolean noLocal)
                                    throws javax.jms.JMSException

Throws:

javax.jms.JMSException

close

public void close()
           throws javax.jms.JMSException

unsubscribe here

Specified by:

close in interface javax.jms.MessageConsumer

Throws:

javax.jms.JMSException

getMessageListener

public javax.jms.MessageListener getMessageListener()
                                             throws javax.jms.JMSException

Specified by:

getMessageListener in interface javax.jms.MessageConsumer

Throws:

javax.jms.JMSException

getMessageSelector

public java.lang.String getMessageSelector()
                                    throws javax.jms.JMSException

Specified by:

getMessageSelector in interface javax.jms.MessageConsumer

Throws:

javax.jms.JMSException

receive

public javax.jms.Message receive()
                          throws javax.jms.JMSException

Specified by:

receive in interface javax.jms.MessageConsumer

Throws:

javax.jms.JMSException

receive

public javax.jms.Message receive(long delay)
                          throws javax.jms.JMSException

Specified by:

receive in interface javax.jms.MessageConsumer

Throws:

javax.jms.JMSException

receiveNoWait

public javax.jms.Message receiveNoWait()
                                throws javax.jms.JMSException

Currently the implementation is such that if no msgListener has been associated to this consumer, the onMessage blocks until receiveNoWait has been invoked (if there is a message pending). This has the disadvantage of blocking subscriptions of other sessions (or subscriptions on other topics). Using the get() method of XmlBlasterAccess would always return the last message (which is not wanted here). TODO we would need something as 'noInitialUpdates' for the getQos.

Specified by:

receiveNoWait in interface javax.jms.MessageConsumer

Throws:

javax.jms.JMSException

setMessageListener

public void setMessageListener(javax.jms.MessageListener msgListener)
                        throws javax.jms.JMSException

Specified by:

setMessageListener in interface javax.jms.MessageConsumer

Throws:

javax.jms.JMSException

update

public java.lang.String update(java.lang.String cbSessionId,
                               UpdateKey updateKey,
                               byte[] content,
                               UpdateQos updateQos)
                        throws XmlBlasterException

Description copied from interface: I_Callback

This is the callback method invoked from I_XmlBlasterAccess informing the client in an asynchronous mode about a new message.

So you should implement in your client code the I_Callback interface - suppling the update() method where you can do with the message whatever you want.

The raw protocol driver specific update() method (e.g. CORBA-BlasterCallback.update()) is unpacked and for each arrived message this update is called.

Specified by:

update in interface I_Callback

Parameters:

cbSessionId - The session ID specified by the client which registered the callback. You can specify a cbSessionId during connection (with ConnectQos) and this is bounced back here so you can authenticate the message.

updateKey - The arrived key containing the topic name

content - The arrived message content. This is your payload.

Throws:

XmlBlasterException

See Also:

I_XmlBlasterAccess