myfaces-users mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "a clem" <>
Subject Re: [Orchestra] Explicit conversation starting and nested conversations
Date Tue, 01 Apr 2008 11:57:19 GMT
Thank's a lot for your response. What I would like to do is to be able
to share a page (ant its backing bean) between 2 conversations types,
like an activity définition can be shared between 2 process definition
in BPM. For exemple, the select customer page can be shared between
the 'send mail' and 'send invoice' use cases. I think I'm going to
hack the source to see how I can achieve this.


On Mon, Mar 31, 2008 at 11:18 PM, simon <> wrote:
> Hi,
>  On Mon, 2008-03-31 at 22:36 +0200, a clem wrote:
>  > Hi,
>  >
>  > I'm currently playing with this great framework Orchestra, trying to
>  > build some small examples and a few questions came to my mind:
>  > Is it possible to start a new conversation explicitly
>  > (programitically). I've looked to the API but there doesn't seem to be
>  > something like a begin or start method in it?
>  Well, there are two answers to this :-)
>  (1)
>  If you configure a bean A in Spring to inject some other bean B that is
>  configured in a conversation scope, then what is actually injected is a
>  proxy. The bean B isn't actually created, and the conversation is not
>  created to hold it (though the conversation might already exist if there
>  are multiple beans in the same conversation).
>  Then if A invokes any method on B, that triggers the creation of an
>  actual instance of B plus the conversation to hold it (if the
>  conversation does not yet exist).
>  So I guess you could call that "programmatic" creation of a
>  conversation; whether B is in the conversation or not is controlled by
>  what A does.
>  (2)
>  But if you mean actually creating a Conversation object then placing
>  objects in it, then no I don't think that is currently possible (or at
>  least not easy).
>  In theory there is no reason why Orchestra couldn't support that, I just
>  think we didn't consider it useful. If there is a good use case then I'm
>  sure that could be added.
>  The principle is simple: create a Conversation object then get a
>  reference to the current ConversationContext and add it. But the problem
>  is that there are a bunch of settings that a conversation can have which
>  are defined by a ConversationFactory (which is a mandatory parameter to
>  the Conversation constructor at the moment). This factory is really
>  expected to be a Spring scope manager object or similar; I don't know if
>  it is possible to look this up nicely, or whether it is actually needed
>  for manually-created conversations. But the settings would need to be
>  defined somewhere.
>  Method ConversationManager.getConversation(name) will return
>  conversations by name, but returns null if the conversation does not
>  exist; I don't think there is a way of forcing it to exist.
>  Note that a bean which is *already* in a conversation can add extra
>  objects to its own conversation via Conversation.setAttribute.
>  > Can the same backing bean belong to more that one conversation type?
>  > In other world can I share a view between multiples conversations? It
>  > seem's that backing beans can only have one conversation name.
>  No, a bean is expected to be in only one conversation. I think things
>  would get quite confusing otherwise. For a start, if persistence is
>  being used with conversations, then a bean could have two persistence
>  contexts associated with it simultaneously which would be tricky :-)
>  A bean in one conversation can quite happily call a bean in another
>  conversation of course (orchestra conversations are not like WebFlow or
>  Seam conversations).
>  What would the use case be for this?
>  >  And
>  > finally, is it possible to have nested conversation contexts? Thank's
>  > for all your coming responses! :)
>  No, but that feature is definitely on the to-do list.
>  Orchestra does support multiple concurrent named conversations, as I'm
>  sure you're aware. That solves many of the use-cases for nested
>  conversations but not all of them.
>  Good questions - I should put these on the Orchestra wiki FAQ page.
>  Unless perhaps you would be willing to do that?
>  Regards,
>  Simon

View raw message