Ok that makes sense thanks for clearing that up

On Thu, Dec 1, 2016 at 11:24 PM, Rob Godfrey <rob.j.godf...@gmail.com>
wrote:

> On Fri, 2 Dec 2016 at 00:01, James Franco <mjfranc...@gmail.com> wrote:
>
> > yes it is the qpid hello world example . In your statement
> >
> > "The binding used depends on the topic type (which the client determines
> by
> > asking the broker) and the subject (or other details of the address).
> Since
> > no 'subject' is specified by default in hello world, and the exchange
> type
> > is a 'topic' exchange that supports wildcarding, the key used for the
> > binding is '#' which matches anything."address). Since no 'subject' is
> > specified by default in hello world, and the exchange type is a 'topic'
> > exchange that supports wildcarding, the key used for the binding is '#'
> > which matches anything."
> >
> > Does that mean if a listener is listening to a TopicExchange instead of a
> > queue then it is bound to all the queues of the exchange (i.e the
> listener
> > will get whatever goes through the exchange to other queues) ?
> >
>
> By definition a listener (consumer) in AMQP 0.x can only listen (consume)
> from a queue (there is no way to listen to an exchange).
>
> The addressing syntax used by the clients is an attempt to abstract away
> from the implementation details (queues and exchanges) into more common
> notions such as topics. If you subscribe to an address like foo/bar which
> you expect to provide topic like semantics... then what the client will be
> doing under the covers is creating a temporary queue, binding that to the
> exchange foo with the binding key bar and then listening for message
> arrivals into that temporary queue. Similarly subscribing to just amq.topic
> will bind (with a wildcard) a temporary queue which will receive all
> messages sent to the exchange. One thing that is very misleading in all
> this is that there is nothing specifically "topic" like about the topic
> exchange... it would have much better been called the wildcard exchange.
> You can equally well get topic like behavior from any of the other exchange
> types
>
> -- Rob
>

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