> The DefaultIndexManagerFactory

I'm not convinced. Why? Sounds confusing to me, and I see no use to do such a thing.

> And this is done by the service implementing Startable and Stopable. If the service is not implementing these services, I am assuming that the service does either not need to be started or already has been started by the provider of this service. Make perfect sense to me.

You wouldn't allow for reuse of the same implementation in different contexts; something that we actually need.

Let's keep in mind this SPI is primarily meant to solve _our_ need to integrate with other projects. Its goal N'1 is to fullfull our practical needs; sure this might need some better javadoc on how it works but I'm not looking into developing a general purpose service framework, that's beyond its scope.