[KCP] SystemChangeNotification: supported events

Daniel Vainsencher danielv at netvision.net.il
Sun Jun 29 12:55:11 UTC 2003


Roel Wuyts <wuyts at iam.unibe.ch> wrote:
> On Saturday, Jun 28, 2003, at 22:35 Europe/Zurich, Daniel Vainsencher 
> wrote:
> > - What does a method/class recategorization trigger?
> 
> Good question, since it is essentially a 'move'. So I guess it should 
> do a removal/addition pair. Or maybe a separate event. It depends on 
> whether anyone needs to know specifically about recategorization.

Just some things to think about -
If you consider methods to be merely behavior of a class, then method
recategorization shouldn't bring up any events at all, because behavior
hasn't changed. This is correct, because it is a view that might be
useful for some applications (concerned with behavior) but it isn't
complete, because other applications are interested in structure
(MudPie), which does change. So maybe having events for both
complementary perspectives is the only way to serve all those needs.

While most applications could be written successful to deal with
recategorization encoded as remove/add, consider that this loses
information, and then applications might need to start interpreting the
event stream to know what really happened (was that really removed, and
I need to run that classes tests again, or was it merely moved?). So it
might be better to consider a richer abstraction of possible events. 

Note that I don't want these meandering thoughts to stop you from
starting to implement something coherent and simple, I just thought I'd
complicate things a little before triage begins...

Daniel



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