Hi Henrik, You are confusing yourself by asking DS for a mixture of field injection, bind/unbind methods and having non-thread-safe code for a dynamic reference.
By applying the annotation to the field you are telling DS to inject references directly into your component's field. You are also telling it to use bind/unbind methods, which it is also doing. The volatile setting is likely changing the result of a race condition that was happening before, where DS injects a one-element collection then starts calling the bind method. In your scenario I would strongly recommend not using field injection (you have bind/unbind methods) by moving the annotation to the bind method. You can then remove the custom bind attribute value and ensure thread safety by using a thread safe collection, or with appropriate synchronisation wherever the list is used. I hope this helps. Regards, Tim Sent from my iPhone > On 20 May 2017, at 21:22, Henrik Niehaus <henrik.nieh...@gmx.de> wrote: > > When I use a Set, bndtools complains, that there is no unbind method, > even though it's specified. But, in my opinion, using a Set only fixes > the symptoms, but not the source of the problem... > > Using CopyOnWriteArrayList does not make any difference. > >> Am 20.05.2017 um 19:42 schrieb Ferry Huberts: >> >> >>> On 20/05/17 18:48, Henrik Niehaus wrote: >>> I noticed a behavior with SCR, which I don't understand. I'm using a >>> multiple dynamic reference for a list like this: >>> >>> @Reference(cardinality = ReferenceCardinality.MULTIPLE, policy = >>> ReferencePolicy.DYNAMIC, bind="addService", unbind="removeService") >>> private List<WeatherService> services = new ArrayList<>(); >> >> Use a Set<> i.s.o. a List<>. >> even better would probably be CopyOnWriteArraySet, depending on your >> usage scenario. >> >>> >>> This works as I expect it. All 5 instances get added to the list. >>> >>> At startup SCR tells me, that it would be a good idea to make this list >>> volatile, which makes sense. So I tried that and ended up with 6 >>> instances in my list, which I don't understand. When I set a breakpoint >>> in the bind method "addService", it turns out, that the list already >>> contains an element when it is called the first time. One service is >>> contained twice in the list. And it is always the service, which is >>> added at last. Is this intended? Am I doing something wrong? >>> >>> - Henrik >>> >>> >>> _______________________________________________ >>> OSGi Developer Mail List >>> osgi-dev@mail.osgi.org >>> https://mail.osgi.org/mailman/listinfo/osgi-dev >>> >> > > _______________________________________________ > OSGi Developer Mail List > osgi-dev@mail.osgi.org > https://mail.osgi.org/mailman/listinfo/osgi-dev _______________________________________________ OSGi Developer Mail List osgi-dev@mail.osgi.org https://mail.osgi.org/mailman/listinfo/osgi-dev
