Re: [wsbpel] Issue 6 - Rough draft of proposal for vote

[andrew.francis@elf.mcgill.ca]

Quoting "Yaron Y. Goland" <ygoland@bea.com>:

> A very common business process design pattern is to have multiple
> simultaneous actions where only one of the actions needs to complete in
> order for the process to continue. A classic example is a search
> operation. The proposal given below enables the programmer to directly
> express this pattern in the BPEL process.

On the "Workflow Patterns" website, van aalst describes two constructs:
"discriminator" and "N-out-of-M" join. What you are describing sounds
like the "discriminator." The discriminator waits for one activity to
complete before starting the next activity. The remaining parallel
activities are allowed to complete but the results are ignored. This
differs from Issue's six's description that talks about terminating
"unnecessary" concurrent activities.

If this is the case, why not construct the more general case, the
"N-out-of-M" join and allow the option to terminate or ignore outstanding
concurrent activities?

Cheer,
Andrew

"Workflow Patterns" website
http://tmitwww.tm.tue.nl/research/patterns/patterns.htm