Re: [jbosscache-dev] Handling invalid nodes

What about doing the isInvalid check(and exception throwing ) in an interceptor that would be AFTER the CacheLoaderInterceptor? Phps CallInterceptor? Manik Surtani wrote: > Guys, > > I've been thinking about behaviour with the Node API, and wonder > what works best from a user standpoint. Consider: > > * User gets a hold of a node and holds on to the ref for > performance reasons (Node n = cache.getNode(fqn)) > * Performs tasks on the node: n.put(), n.get(), etc. > * Node checks for validity before performing any API calls, > throwing a NodeNotValidException if the node is not valid anymore. > > Nodes get marked as invalid if they are removed or moved by a > concurrent thread, or invalidated by a remote one. Eviction did > not mark a node as invalid, but I think this is inconsistent and a > bug: eviction too should mark the node as invalid. > > So the question is this - with potentially likely events marking a > node as invalid - especially with eviction - should we throw a > NodeNotValidException? Since (as of 2.1.0), the Node > implementation that a user has is an instance of > NodeInvocationDelegate which in turn has a reference to an > UnversionedNode, perhaps we should handle the NNVE within the > NodeInvocationDelegate and perform a lookup internally and refresh > the UnversionedNode reference, and THEN throw a NNVE if we can't > fetch the node? > > Th drawback is that this is potentially two calls for what should > be one - node gets evicted, we call cache.getNode() internally to > refresh the reference (from a cache loader, etc), and then invoke > whatever call the user intended to call up the interceptor chain. > The benefit is a smoother user experience. > > Thoughts/opinions? > > Cheers, > -- > Manik Surtani > Lead, JBoss Cache > manik(a)jboss.org > > > > > > > _______________________________________________ > jbosscache-dev mailing list > jbosscache-dev(a)lists.jboss.org > https://lists.jboss.org/mailman/listinfo/jbosscache-dev