On 8/17/06, Naveen Rawat <[EMAIL PROTECTED]> wrote:
Great James
Your suggestion is working. A major hurdle seems solved.
A little query down there.
> > Hi James,
> >
> > Thanks for your response.
> >
> >
> > > Are you trying to implement request-response with A, B, C making
> > > requests on Z and getting the response? Or can A, B, C process any
> > > message from Z?
> >
> >
> > Exactly the first case.
> > A, B, C making requests on Z and getting the response from Z
> >
> >
> >
> > > I'm not sure if your issue is that say A doesn't see the responses for
> > > its request (if thats the case use either 3 queues, use temporary
> > > queues for the responses or use a selector and a correlationID on the
> > > request & response) - or is it that you have a small number of
> > > responses from Z and they are being hogged by one consumer - in which
> > > case setting a small prefetch and a round robin dispatch policy will
> > > fix this.
> >
> >
> > Its that, A doesn't see the responses for its requests made.
> >
> > I would really appreciate if I can get some help stuff on -
> > 1) Creating, destroying and maintaining data in temporary queues.
> > 2) Setting selector and correlationID in messages.
>
> Details here
>
>
http://incubator.apache.org/activemq/how-should-i-implement-request-response-with-jms.html
>
> for 1) just call session.createTemporaryQueue() and set that queue on
> the Message.setJMSReplyTo() property so that services can reply to
> your temporary queue. They are deleted when A terminates so there's no
> issue with maintaining data.
>
> for 2) just add a JMSCorrelationID() to the request messages you send
> as requests. You can then use a selector such as "JMSCorrelationID =
> 'abc'" on the consumer for responses so that responses are filtered to
> only return A's results etc
I went for this (2nd) one. Even though now a result is obtained, I would
like to ask which one approach is more favoured by you.
Is it the temporary queues overhead matter that makes 2nd score over 1st?
Any other reason please tell.
The main difference is, do you want the response to be persistent.
e.g. if A dies and comes back again later - do you want it to resume
processing old results? In which case use a persistent queue and
correlation IDs. If the responses are transient then use a temporary
queue so the old messages get discarded by the broker when A dies.
--
James
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http://radio.weblogs.com/0112098/
