Yes you should create a new consumer object. You can certainly reuse connections and sessions but you will want to call createConsumer() on the session to get a new consumer if you close the old one. If you create a new consumer the you should start receiving messages again.
On Wed, Jun 10, 2015 at 6:44 AM, spam trap < nospam.1.friedbad...@spamgourmet.com> wrote: > On Tue, 9 Jun 2015 10:31:02 -0400, Christopher Shannon > <christopher.l.shan...@gmail.com> wrote: > > OK. Thanks. > > Now I am looking at the case where we want messages to be redelivered > to the same consumer (assume there is only one consumer of a queue). I > have tried stopping and restarting the session and consumer objects > but not all messages are redelivered. > > The following article seems to suggest that you must close the > consumer object > (http://activemq.apache.org/what-is-the-prefetch-limit-for.html) > but if I try this and then attempt to restart it, no messages are > consumed at all, even new ones. > > How can I achieve the latter? Do I need to destroy and recreate the > consumer object, for example? > > >I think the only way you are going to be able to achieve what you want is > >by doing what Tim mentioned....using a transaction where you > >commit/rollback after each message. Since processing a message could take > >a while, you could increase the number of consumers to increase > throughput. > > > > > >Take a look at the documentation here: > >http://activemq.apache.org/message-redelivery-and-dlq-handling.html for > >more info on how messages can be redelivered. > > > >On Tue, Jun 9, 2015 at 9:51 AM, spamtrap < > >nospam.1.friedbad...@spamgourmet.com> wrote: > > > >> On Tue, 9 Jun 2015 07:29:16 -0600, Tim Bain > >> <tb...@alumni.duke.edu> wrote: > >> > >> >So why can't you use transactions? Won't you get what you want if you > >> >commit the transaction after every successful message and > >> >rollback()/close() and then reconnect after every failed one? > >> > >> No. It may take some time to process a message so we operate a > >> 'window'. Therefore there would normally be more than one message > >> outstanding. > >> > >> >Also is the app server going to fail to respond to *certain* messages, > or > >> >is it going to fail to respond to *any* messages? If the latter, you > can > >> >delay the reconnect till you figure out that the web service is > available > >> >again. > >> > >> We have to assume it may fail to respond to certain messages. > >> > >> >On Tue, Jun 9, 2015 at 7:09 AM, spamtrap < > >> >nospam.1.friedbad...@spamgourmet.com> wrote: > >> > > >> >> On Tue, 9 Jun 2015 06:43:45 -0600, Tim Bain > >> >> <tb...@alumni.duke.edu> wrote: > >> >> > >> >> The situation is that the consumer gets a message from a queue and > >> >> then converts into into a different format and sends it to an > >> >> application server, which should respond with an acknowledgement > >> >> message. If the application server does not respond to a particular > >> >> message then we want to be able to allow another ActiveMQ consumer to > >> >> pick up the message and send it elsewhere. Any consumer should be > >> >> able to process the message so we don't want to use selectors. > >> >> > >> >> >In this scenario, do you want to consume it twice, or do you really > >> want > >> >> to > >> >> >consume it once but you're picking which consumer gets it? If the > >> latter, > >> >> >can you use selectors to make sure the right consumer gets the right > >> >> >messages? Or maybe an embedded Camel route to send those messages > to a > >> >> >queue that's specific to the consumer that should get them? > >> >> >On Jun 9, 2015 6:00 AM, "spamtrap" < > >> nospam.1.friedbad...@spamgourmet.com> > >> >> >wrote: > >> >> > > >> >> >> On Tue, 9 Jun 2015 07:24:24 -0400, Christopher Shannon > >> >> >> <christopher.l.shan...@gmail.com> wrote: > >> >> >> > >> >> >> >The use case you are trying to achieve is probably best done by > >> using a > >> >> >> >transaction instead of individual acknowledgements. If you call > >> >> rollback > >> >> >> >on the session then the message would be available to be > >> redelivered to > >> >> >> >another consumer. > >> >> >> > >> >> >> I don't think I can use a transaction because all messages are > >> >> >> committed at once. We need to be able to select which messages > may > >> be > >> >> >> redelivered and which not, hence the individual acknowledge mode > is > >> >> >> used. > >> >> >> > >> >> >> Will the rollback work with individual acknowledgements? > >> >> >> > >> >> >> > >> >> >> > > >> >> >> >On Tue, Jun 9, 2015 at 3:50 AM, spamtrap < > >> >> >> >nospam.1.friedbad...@spamgourmet.com> wrote: > >> >> >> > > >> >> >> >> Hi, > >> >> >> >> > >> >> >> >> In some cases we want to allow another consumer to consumer a > >> message > >> >> >> >> that has already been consumed. The session is opened using > >> >> >> >> INDIVIDUAL_ACKNOWLEDGE and the message has not been > >> acknowledged. I > >> >> >> >> have tried closing the session where the message has been > consumed > >> >> but > >> >> >> >> the message is not available to the other consumer. How can I > >> >> achieve > >> >> >> >> what I need? > >> >> >> >> > >> >> >> >> TIA. > >> >> >> >> > >> >> >> >> > >> >> >> >> > >> >> >> > >> >> >> > >> >> >> > >> >> > >> >> > >> >> > >> > >> > >> > >
