On conversation usage patterns

[rdewell]

To prefix: I'm using Seam extended managed transactions.

I've run into a use-case that seems to lie somewhere in the realm of conversations, yet doesn't quite fit current conversational semantics exactly.

Obviously conversations seem best suited to a page-to-page wizard style UI. A flow with definite beginning, middle, and end that lends itself to using @Begin and @End.

But, what about a (potentially) long running "conversation" that does not fit as neatly into this pattern?

Example: a single view that has many forms, and thus may span many submit/request cycles in and of itself. The entire usage pattern of this single view IS a long running conversation. However, because you are explicitly making changes/actions via the multiple granular forms on this view, there is never a needed or logical necessity to "end" the conversation on that view. You end it, really, by navigating away from the view.

To be more specific, this view's purpose is as a kind of "component builder". All of the actions and granular forms are working with a single component and its subcomponents in various ways, building and editing that component.

Thus, you could describe it as a freeform conversation rather than a directed conversation. I guess that kind of gets to the heart of the question: freeform long running conversations vs. directed (wizard style) long running conversations. Seam conversations right now seemed to be geared towards the latter. I'm at odds on how best to handle the former.

Perhaps at each action on this view I should grab the UserTransaction and call commit on it manually? Then, just let Seam timeout out the conversation since @End will never be called. Does that sound right?

Thoughts?

Ryan

[rdewell]

Perhaps it's the notion of a "save point" that I'm getting at? A point intermediary to the explicit end of the conversation where progress is committed, but the conversation is NOT ended.

For the UserTransaction, it would be a "commit/begin", and the current conversation bean(s) would stay a part of the current conversation.

This would be great as an conversation related annotation. @Savepoint, or something similar.

Ryan

[gavin.king]

I think either are perfectly doable in Seam. I mean, logically, there is only two ways a conversation could be "cleaned up".

(1) the app explicitly indicates the conversation is over
(2) the conversation times out

Both logical possibilities are supported. Hence, *anything* that is doable is doable using the current model :-)

My reverse engineered crud app stuff has the freeform model you are describing, btw.

[gavin.king]

As for "savepoints", I assume that you mean you are using FlushMode.NEVER. Well, in that case, you can have as many explicit flushes as you like in a single conversation. So this is also supported.

[rdewell]

Thanks for the input. RE: "My reverse engineered crud app stuff has the freeform model you are describing".

I'm not sure where that's located at? I'd like to take a look and compare it to what I'm doing.

Ryan

[lavoir]

"rdewell" wrote:
Thanks for the input. RE: "My reverse engineered crud app stuff has the freeform model you are describing".

I'm not sure where that's located at? I'd like to take a look and compare it to what I'm doing.

Ryan

I d like to have a look at it too :)

[andrewa]

from CVS: examples/crud

[gavin.king]

Nope, actually, it is stuff in Hibernate Tools. What I might do is check one of my reverse engineered applications into the examples/crud directory.

Unfortunately, to actually run this stuff, you need to upgrade JBoss to use the brand new releases of Hibernate 3.1, Hibernate Annotations and Hibernate EntityManager.

[lavoir]

Just ran through the generate crud code, looks nice.

Question though, why are you not using a resource bundle?

I always wondered the same when it came to the examples, but figured, Eh, they are just examples.

[gavin.king]

Sure, it would make perfect sense to use a resource bundle. Just did not get time to futz with that stuff yet.

Are you volunteering to patch the velocity templates to do this? :-)

[lavoir]

I'll definatetly have a look :)

[marius.oancea]

Gavin, would you be so kind to put one generated example into examples directory. Will be of much interes for all of us.

[manuel.gentile]

i did not find crud example in the hibernate tool cvs?
where is it ?

thanks

[gavin.king]

I'll definatetly have a look :)

Well, I beat you to it ;)

In CVS.

[lavoir]

I'll definatetly have a look :)

Well, I beat you to it ;)

In CVS.

I just sa that tonight looking through some generated code :)