[news.eclipse.technology.equinox] Re: Plugins - singletons or not?

["Jeff McAffer" <jeff_mcaffer_REMOVE@xxxxxxxxxx>]

Great.  Thanks for the clarification.  Makes sense.

Jeff

"pkriens" <Peter.Kriens@xxxxxxxx> wrote in message
news:3E89E264.5040302@xxxxxxxxxxx
> Yes. your recap is correct.
>
> A refresh is not a framework restart (though it might be implemented as
> such for simple minded implementers). The parameter to the refresh is a
> set of bundles. The implementation is supposed to calculate the closure
> of all dependent bundles and restart those. So -at least- the affected
> bundles should be stopped and started again (which effectively creates a
> new ClassLoader for each). Good implementations minize the set of
> affected bundles though this is not a trivial calculation.
>
> Kind regards,
>
> Peter Kriens
>
>
> Jeff McAffer wrote:
>
> > Just to recap then.
> > "eager" = restart all dependents when a prereq changes
> > "lazy" = wait until an explicit framework restart/refresh to hook the
new
> > packages into the global namespace.
> > Is this close?  Assuming it is,
> >
> > What happens during the refresh?  Is this effectively a framework
restart
> > where everything is shutdown and restarted?  If not, how do the
dependents
> > of some updated bundle know to drop their references to old classes and
get
> > new ones?
> >
> > Jeff
> >
> > "pkriens" <Peter.Kriens@xxxxxxxx> wrote in message
> > news:3E893936.8000104@xxxxxxxxxxx
> >
> >>Jeff McAffer wrote:
> >>
> >>
> >>>In OSGi (at least some older versions) the old bundle (B) would stay
> >>>
> > around
> >
> >>>until the framework was restarted or all dependent bundles were
shutdown
> >>>
> > and
> >
> >>>restarted.  Is this still the state of the art in OSGi?
> >>>
> >>In release 1 some frameworks refreshed "eagerly", restarting any
> >>dependent bundles, other frameworks left the packages lying around and
> >>resolved the problem lazy. In release 2 we mandate the lazy approach but
> >>provide a special service, the PackageAdmin service that allows the
> >>Management Agent to initiate a refresh (and expose the current status of
> >>package sharing). The refresh can do a global refresh or for a set of
> >>bundles.
> >>
> >>The idea behind this is that a management agent can install several
> >>bundles before it refreshes saving time and some error scenarios.
> >>
> >>BTW, what stayed around were exported packages not the bundle.
> >>
> >>Kind regards,
> >>
> >>Peter Kriens
> >>
> >>
> >>
> >>>Jeff
> >>>
> >>>
> >>>
> >>>
> >
> >
>