Unless your queue went away, you should still be able to get a reference to
it.  What you are still missing though is that there is not a way with the
current JMS api anyway to remove a message from a queue.  You may be able do
this with the JMS implementation's native api though.  But still, unless you
can somehow stop the queue, when browsing you are still just getting a
snapshot of what WAS on the queue when the call was made.  I like the other
implementations people have been suggesting to you about building in support
downstream (in the MDB or further) to support a cancel.

Chris Thompson
Bean-test Developer
http://www.empirix.com

-----Original Message-----
From: Alvin Wang [mailto:[EMAIL PROTECTED]]
Sent: Wednesday, March 20, 2002 2:12 PM
Subject: Re: AW: [EJB-INT] Is MDB the best choice for asynchronous
request han dling in EJB?


Nicholas, for the QueueBrowser solution, when the user returns to cancel, he
has no way to retrieve the last QueueSession to retrieve the QueueBrowser.
Am I wrong? Thanks!



-----Original Message-----
From: A mailing list for Enterprise JavaBeans development
[mailto:[EMAIL PROTECTED]]On Behalf Of Nicholas
Sent: Tuesday, March 19, 2002 10:15 AM
To: [EMAIL PROTECTED]
Subject: Re: AW: [EJB-INT] Is MDB the best choice for asynchronous
request han dling in EJB?


I do not know of any specific MDB perfomance issues.
Can you elaborate ?

Also, technically, if the message has been sent to a
queue, and you have somehow persisted or "remembered"
any uniquer attributes of the message (like mesage ID
for example), you could use a queue browser to remove
the message before it is processed. However, I would
imaguine it unlikely that you would be able to grab
the message before it was processed if you do have
decent performance.

In general, I am in the same mind as Chan. You should
cancel undesired asych requests before they are sent.
It is a difficult proposal to cancel any sort of
asynch request without going out of band.

//Nicholas

--- Chan Philip <[EMAIL PROTECTED]>
wrote:
> The Request should has been cancelled before, not
> after, it is sent.
>
> -----Urspr|ngliche Nachricht-----
> Von: Alvin Wang [mailto:[EMAIL PROTECTED]]
> Gesendet: Montag, 18. Mdrz 2002 19:52
> An: [EMAIL PROTECTED]
> Betreff: Re: [EJB-INT] Is MDB the best choice for
> asynchronous request
> handling in EJB?
>
>
> For example, I cannot cancel a request in the queue,
> and the performance
> issue...
>
> -----Original Message-----
> From: A mailing list for Enterprise JavaBeans
> development
> [mailto:[EMAIL PROTECTED]]On Behalf Of Johan
> Eltes
> Sent: Monday, March 18, 2002 12:57 PM
> To: [EMAIL PROTECTED]
> Subject: Re: Is MDB the best choice for asynchronous
> request handling in
> EJB?
>
>
> What kind of limitations are you experiencing?
>
> /Johan
>
> -----Original Message-----
> From: A mailing list for Enterprise JavaBeans
> development
> [mailto:[EMAIL PROTECTED]]On Behalf Of Alvin
> Wang
> Sent: den 18 mars 2002 16:41
> To: [EMAIL PROTECTED]
> Subject: Is MDB the best choice for asynchronous
> request handling in EJB?
>
> Hi! We need to do some asynchronous request handling
> work in EJB. For
> example, the user sunmits a request and quits, and
> later he comes back and
> check the status/result of his request. Currently we
> are using MDB to do
> this. However, we feel that there are some
> limitations in MDB and JMS. Is
> MDB the most natural way to handle asynchronous
> request in EJB? Can any guru
> give us some alternative design strategies? Thanks!
>
> Alvin
>
>
==========================================================================To
> unsubscribe, send email to [EMAIL PROTECTED] and
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>


=====
Nicholas Whitehead
Home: (973) 377 9335
Cell: (201) 615 2716
Work: (212) 235 5783
[EMAIL PROTECTED]

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