Re: [wsbpel] implicite links of the runtime engine (was: Implicit<sequence> macro)

["Monica J. Martin" <monica.martin@sun.com>]

Frank Leymann wrote:

>Edwin,
>
>this was EXACTLY my reaction too!
>
>Assaf,
>
>I would appreciate an example of a business process that contains "wild
>cycles", and I would like to see a written down description of what the
>semantics of these loops are (two "intersecting" cycles suffice), a
>description of how you cope with races in the process, with one and the
>same activity being activited multiple time and at the same time (!), with
>concurrency issues on affected variables etc.. Thanks!
>
>Ron,
>
>what I do is I sit down with those customers who tell me that they need
>arbitrary cycles and I walk with them through their examples.  I discuss
>with them what they intended to express/specify with the cycles, and how
>these cycles should be interpreted.  Most often, different people in the
>room interprete the cycles differently and thus, they soon realize that
>this is no good.  Or I walk them through the effect of arbitrary cycles and
>discuss with them the issues above and the various alternatives how these
>issues may be resolved; and nearly always, different people in the room
>want different ways to resolve the issues - and they soon realize that this
>is no good.  Most often, the conclusion is that arbitrary cycles are to be
>avoided:  Otherwise the language will become much more complicated based on
>additional attributes of constructs and resulting complications to
>comprehend a model.  To state it explicitly: Just allowing arbitrary cycles
>is NOT enough, but you need to introduce a bunch of additional language
>elements to control the operational semantics of these cycles, a fixed
>"simple" operational semantics won't suffice.  Based on my experience the
>"controlled cycles" are not only sufficient according to the 80:20 rule but
>according to the 99:1 rule - and then it's a business decision whether or
>not to go for the 1%.
>  
>
mm1: As you have asked Assaf to provide, Frank, suggest you provide a 
use case to show the examples that customers usually associate with
cycles for this TC to evaluate.

Thanks.