[infinispan-dev] Cache entry not invalidated callback?

Hi, Re: Porting over http://opensource.atlassian.com/projects/hibernate/browse/HHH-3818 to Infinispan 2nd level cache. For HHH-3818, Brian used the cache as a bus to notify that the cache contents where invalid. To do so, he implemented cache entry modified and invalidated callbacks that react to cache modifications or invalidations where the FQN is an internal fqn which contains the local address. Now, the trick he uses for the invalidation is that on startup or whenever there's a view change, he establishes these internal FQNs in each node for each of the members in the cluster, i.e. fqn=/test/com/foo/test/ENTITY/NODE/127.0.0.1:39104 So, in an invalidation scenario, if you a node puts something on /test/com/foo/test/ENTITY/NODE/127.0.0.1:39104, the other nodes have at least /test/com/foo/test/ENTITY/NODE/127.0.0.1:39104 created on their caches which means that the invalidation callback works fine cos the FQN exists in other nodes. Now, in Infinispan's case, bearing in mind that there're no FQNs, I could set up such keys when there's a view change too. However, I was thinking of another alternative. Currently, cache invalidation callback fails on Infinispan because when you do a put on key=127.0.0.1:39104, the other nodes do not contain the key=127.0.0.1:39104, so no invalidation callback is received. So, my suggestion is the following: Why not have a callback saying: "I attempted to do an invalidation on k=x but k=x did not exist". Maybe something like CacheEntryNotInvalidated callback? It looks to me that it'd be relatively simply to implement such notification and would simplify the code on the Infinispan 2nd level cache provider. Thoughts? -- Galder Zamarreño Sr. Software Engineer Infinispan, JBoss Cache