On 01/04/2008, xjn <[EMAIL PROTECTED]> wrote: > > Hi, > > thx for your answer, but it does not fit my needs ... > > I try to make it cleaner : > > - i have an unknown number of message producers > - i have an unknown number of message consumers > - the message(s) is/are well defined > - every time a client connects, the last state an then the state changes > should be visible to the client(s) > > - a client may connect after a long period, so processing all 'in between' > messages is not a deal > > > To have an example, please assume there is a buildung, with many on/off > contacts for any kind of thing you imagine. > And every time for a new tenant, there are contacts of differrent kind > added/removed. > > Then there are a number of clients (the tenant, security,...), who are > interested in the native/interpreted state of the contacts, some client > every second, some one time every month or on startup. > > I'm not able to find a pattern to solve this kind of (stateful) messaging
See Last Image Caching which uses non-persistent topic subscriptions but allows you to provide the 'last image' first before any further updates... http://activemq.apache.org/subscription-recovery-policy.html -- James ------- http://macstrac.blogspot.com/ Open Source Integration http://open.iona.com
