Hi,
While working on SLING-4851 to extract the launchpad start levels
sequencing logic (aka "wait for the installer to do its thing at each
increasing start level") into independent bundles, I wrote a proof of
concept using the following API:
public interface StartLevelChangeBarrier {
CountDownLatch getStartLevelLatch(int startLevel);
}
Modules can supply such a service so that the new start levels
sequencer waits for their CountDownLatches to go to zero before
proceeding to the next start level.
The main advantage is that this avoids the current 2-seconds delay
between start levels that the launchpad currently needs, if we can
adapt the OSGi installer to provide this service efficiently. And if
the installer still needs this delay, it would at least be internal to
that module.
See the ticket for more details, feedback is welcome - I might not
work on this again for about two weeks but as usual feel free to steal
the good ideas if there are any ;-)
-Bertrand
