Re: Steps with non-connected outputs

On 4/13/07, Norman Walsh <Norman.Walsh@sun.com> wrote:
> / Alex Milowski <alex@milowski.org> was heard to say:
> | In my model, we have the following time sequence for the lifetime of
> | a step:
> |
> | 1. Initialization of the component happens.  This is typically while the
> |    pipeline itself is being initialized.  This is a event that probably
> | happens
> |    outside our specification.
> |
> | 2. Resources that are statically known and bound to input ports are made
> |    available to  steps.  This allows steps to detect errors staticially (
> | e.g. I can't
> |    locate or compile the XSLT transform).  This is an optimization but a
> | very
> |    important one.
> |
> | 3. Output ports are bound to their recipients.
> |
> | 4. The pipeline starts and the step is notified.
> |
> | 5. Some sequence of documents are received (or "pulled") on the
> |    input ports for the step.
> |
> | 6. The pipeline ends and the step is notified.
> |
> | I think our specification needs to allow for 1-3 but needs to focus on
> | 4-6 as standard semantics.
>
> That is waaayyyy more than we want to say. Or at least, it's way more
> than *I* want to say. I think it's something like this:
>
> 1. Initialization of the component happens.
>
> Clearly outside our scope.
>
> 2. The pipeline starts running.
>
> Well, duh, how else is anything ever going to happen.
>
> 3. Each step is run. Steps that occur inside for-each may run more than
>    once.

And a step inside a p:when ? or in p:catch ?

>
> 4. Each step reads as much of its input as it wants. There's no
>    gaurantee that all input is avialable when execution begins. Steps
>    may have to block waiting for input. There's no gaurantee that all
>    steps read all their inputs.
>
> 5. Steps produce their output, if any.
>
> 6. Each step stops.
>
> 7. The pipeline stops.
>
>                                         Be seeing you,
>                                           norm
>
> --
> Norman Walsh
> XML Standards Architect
> Sun Microsystems, Inc.
>
>


-- 
Innovimax SARL
Consulting, Training & XML Development
9, impasse des Orteaux
75020 Paris
Tel : +33 8 72 475787
Fax : +33 1 4356 1746
http://www.innovimax.fr
RCS Paris 488.018.631
SARL au capital de 10.000 €

Received on Friday, 13 April 2007 19:16:46 UTC