Re: [cdi-dev] On @Observes for async events

> Slightly off topic perhaps, but @Stateless is difficult to map to a >(CDI) scope. Everytime a method is called on a proxy, a different actual >bean instance can be used That is EXACTLY as NormalScoped beans are handled. Just think of @Stateless as a @PoolScoped CDI bean. And then you are almost there… It’s basically @RequestScoped with re-using instances by putting them back into a poll cache (like we had it with JSP tags in the old days). And of course with a few default Interceptors. But that’s really it. LieGrue, strub > Am 19.03.2015 um 19:14 schrieb arjan tijms <arjan.tijms(a)gmail.com&gt;: > > Hi > > On Thursday, March 19, 2015, Mark Struberg <struberg(a)yahoo.de&gt; wrote: > >> but opposed to ee concurrency utilities > > > > I thought this was by mistake rather than design? > > > > As far as I remember there was a long discussion on the EJB EG and it >was intentionally that @Asynchronous does NOT propagate any information >about the session, security, and don’t even share the same pool instance >from @Stateless (pool ~what we have as @RequestScoped). > > Slightly off topic perhaps, but @Stateless is difficult to map to a >(CDI) scope. Everytime a method is called on a proxy, a different actual >bean instance can be used (but it can also be the same bean instance as >used for the previous call from the same thread) > > The concept is actually not that far removed from a message passing >paradigm, but using synchronous communication and a typed target. > > Kind regards, > Arjan Tijms > > > > The reason is that EJB is all about removing concurrency complexity >from the user as good as possible. The other problem is that you don’t >have it under control how long the new thread will run. And the Session >might be looong time dead already. Another issue is with TX handling. >The JPA spec and also JTA spec (TransactionSynchronizationRegistry) >defines that a transaction must not be used ‚concurrently‘. Means they >only must be assigned to a very single Thread. > > Even with servlet 3.0 async requests you have a ServletRequest only >attached to a very single thread AT EACH TIME (means the thread might >switch, but it’s max 1 at a time). > > > > LieGrue, > strub > _______________________________________________ > cdi-dev mailing list > cdi-dev(a)lists.jboss.org > https://lists.jboss.org/mailman/listinfo/cdi-dev > > Note that for all code provided on this list, the provider licenses the >code under the Apache License, Version 2 >(http://www.apache.org/licenses/LICENSE-2.0.html). For all other ideas >provided on this list, the provider waives all patent and other >intellectual property rights inherent in such information. _______________________________________________ cdi-dev mailing list cdi-dev(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/cdi-dev Note that for all code provided on this list, the provider licenses the code under the Apache License, Version 2 (http://www.apache.org/licenses/LICENSE-2.0.html). For all other ideas provided on this list, the provider waives all patent and other intellectual property rights inherent in such information.