Hi Clement, thank you very much for your fast reply.
I have forgotten to mention, that the service BETA is stated as 'optional' within ALPHA (@Requires(optional=true)). Thus the injected proxy object returns NULL on calling the method 'getData' of BETA, if BETA is unavailable. Only the helper object (WORKER) receives the RuntimeException. It is a little confusing, as this should be the same proxy object !? I could make the WORKER class a Component, but how can I create the actual object instance during runtime for a Component ? Or is there a better way to accomplish this ? Regards, Thorsten On 15.06.2011, at 09:21, Clement Escoffier wrote: > Hi, > > On 14.06.2011, at 23:51, Thorsten Sprenger wrote: > >> Hi, >> >> I have a question concerning iPOJO and services with using a service within >> a subclass object of another service. >> The special case for which I need support is, when the accessed service >> becomes unavailable. >> >> I have two services ALPHA and BETA with a method 'getData'. >> The service ALPHA is spawning several objects (class WORKER, part of the >> ALPHA bundle) during runtime. Each WORKER object needs to access the service >> BETA. >> >> How can this be accomplished correctly ? >> >> The service ALPHA has a reference to BETA via field injection and I provide >> the BETA object reference to each spawned WORKER object upon creation of the >> WORKER object. >> >> If I access BETA from ALPHA directly, everything works as expected: if BETA >> becomes unavailable, getData returns NULL. >> But if I access BETA from the WORKER object, calling getData will throw a >> RuntimeException if BETA becomes unavailable. >> >> Is this the correct behavior ? > > Yes it is. The reason is that iPOJO injects proxies by default. Using proxies > allow you to give a service object to inner classes or helper objects. If the > service on which the proxy delegates, becomes unavailable, the proxy cannot > delegate to the service anymore. The main component instance is invalidated, > but for inner classes (or helper objects), a RuntimeException is thrown > because iPOJO does not control the lifecycle of those objects. > > Regards, > > Clement > >> How should I change my code or design, that I can access services from a >> subclass object ? >> >> Many thanks in advance ! >> >> Regards, >> Thorsten >> --------------------------------------------------------------------- >> To unsubscribe, e-mail: [email protected] >> For additional commands, e-mail: [email protected] >> > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: [email protected] > For additional commands, e-mail: [email protected] > > --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
