Mailing-List: contact users-help@activemq.apache.org; run by ezmlm
Precedence: bulk
Reply-To: users@activemq.apache.org
Received-SPF: pass (athena.apache.org: local policy)
From: uma_rk@comcast.net
To: users@activemq.apache.org
Cc: "Mario Siegenthaler" <msiegenthaler@inventsoft.ch>
Subject: Re: Synchronous "Are you there?" using JMS
Date: Fri, 03 Aug 2007 05:32:05 +0000
Message-Id: 
 <080320070532.11183.46B2BDD50004ACB000002BAF2200760180059DA10E039A@comcast.net>

Hi,

I just need to be able to ping a functional component from another
functional component in a distributed application synchronously.
How can this be accomplished using JMS?

It appears its not straightforward?

Thanks,

/U

 -------------- Original message ----------------------
From: "Mario Siegenthaler" <msiegenthaler@inventsoft.ch>
> Just a thought, but why don't you use a topic for this? I think a
> queue will cause problems because the message will be stored. So the
> "I'm here" thing would possibly refer to an older question and would
> no longer be relevant.
> Hm, just reread your question, and realized that you directly want to
> process the clients ack. I don't think that'll work. How'd you receive
> the ack? Maybe a possiblity would be to define a max
> queue/topic-buffer size of 1 and then the send would block until the
> message is received. Another way would be to actually send a response
> and the asker would just wait for a different message on a temporary
> queue/topic. There's some utility in the JMS-API to do that.. sadly I
> can never it's name.
> 
> Mario
> 
> On 8/3/07, uma_rk@comcast.net <uma_rk@comcast.net> wrote:
> >
> > I have two entities on either side of a queue. Entity A needs to do a
> > synchronous "are you there?" on the queue and receive a response
> > synchronously from Entity B.
> >
> > I thought I'd do this:
> >   - Define a Queue "Are you there" and dispatchAsync = false
> >   - create a session with CLIENT_ACK set
> >   - send "are you there" message to the queue
> >
> > The receiver would acknowledge the message in the onMessage()
> > method.
> >
> > However, I would like for the sender to time out if the ack is not received
> > within a specified time. I see no option to do this which is obvious.
> > How do I make sure that a synchronous send times out if the response
> > is not received within a specified interval?
> >
> > Regards
> >
> > /U
> >
> >
> >