Hi, just an update. We found out that there was a client subscribed to the incriminated topic with a double wildcard char: "/prj/plantid/+/gwid/+/connection_state". So, there is a step 0 to add to the ones in my previous post: "0) connect a client and subscribe the topic /prj/plantid/+/gwid/+/connection_state". It seems that it breaks something somewhere. When, in a second moment, I subscribe the punctual topic "/prj/plantid/111111/gwid/22222/connection_state" and the generic one "/prj/plantid/111111/gwid/22222/#", after the disconnection it is no more possible to subscribe the specific one. It seems like the unsubscribe method doesn't free the "link" between the punctual address and the generic one. Thus, any following subscribe event to the punctual topic throws a nullPointer exception.
Is it possible that something is wrong in the "WildcardAddressManager.java" class, for methods "private synchronized void removeAndUpdateAddressMap(final Address address) throws Exception" and "public boolean addBinding(final Binding binding) throws Exception"? Francesco -- View this message in context: http://activemq.2283324.n4.nabble.com/ARTEMIS-java-lang-NullPointerException-switching-subscription-with-tp4726641p4727006.html Sent from the ActiveMQ - User mailing list archive at Nabble.com.