For a topic subscription, the prefetch buffer is not maintained in memory by the broker, so you would need prefetch=0 which is a little odd for a topic. Would a queue not be better for this use case? Or a virtual topic, where each consumer gets its own queue.
On 18 July 2012 15:17, Alistair Young <alistair.yo...@uhi.ac.uk> wrote: > Perhaps getting at the prefetch buffer would prolly be better in that case. > Would you have a pointer on how to access it? > > Use case is a consumer that populates Active Directory and uses auto > acknowledge. If the AD bit slows down for any reason the topic should fill > up with messages and I need to provide a way for the support team to see if > an account is in the 'queue', i.e. it's been sent to the broker but not been > consumed yet. The query will be based on a userid which is contained in the > message body. Of course I might have missed an entirely easier way of doing > it. It's in conjunction with Camel routing so I could prolly do something > with a Processor or fancy logging but for the most part the consumer rarely > slows down and logging thousands of usernames seems a bit over the top on > the off chance one might be queried. > > > Alistair > > > > mov eax,1 > mov ebx,0 > int 80h > >>>> Gary Tully <gary.tu...@gmail.com> 18/07/12 3:05 PM >>> > > you would be on the right track. > you will need to lock the pending cursor for the duration of the > iteration so that will be a little expensive. > > the pending cursor only gets filled when the prefetch buffer is > filled, so you would need a low prefetch and a slow consumer if you > expect to find messages in there. > What is the use case here? > > On 18 July 2012 14:46, Alistair Young <alistair.yo...@uhi.ac.uk> wrote: >> would I be on the right path if I implemented it in TopicSubscriptionView >> and making use of PendingMessageCursor from TopicSubscription to get at >> the >> pending messages and their content and properties? Or is iterating >> PendingMessageCursor expensive? >> >> >> Alistair >> >> >> mov eax,1 >> mov ebx,0 >> int 80h >> >>>>> Gary Tully <gary.tu...@gmail.com> 18/07/12 1:16 PM >>> >> >> that feature does not exist, it would require some extension to >> org.apache.activemq.broker.jmx.TopicSubscriptionView >> >> On 18 July 2012 11:21, Alistair Young <alistair.yo...@uhi.ac.uk> wrote: >>> Is there a way to find a particular message in a topic, either via a >>> header >>> name/value or based on message content? e.g. if I have a message I know >>> may >>> be in the topic and it has a message body that would match a particular >>> regex, or has a header name with a particular value, is it possible to >>> find >>> it and therefore verify it's in the topic, i.e. it's in the backlog >>> waiting >>> to be consumed? >>> >>> thanks, >>> >>> Alistair >>> >>> >>> mov eax,1 >>> mov ebx,0 >>> int 80h >>> >> >> >> >> -- >> http://fusesource.com >> http://blog.garytully.com > > > > -- > http://fusesource.com > http://blog.garytully.com -- http://fusesource.com http://blog.garytully.com
