Hi,

The problem is that jPDL navigation is constrained (by contrast to JSF or Seam navigation which are free form).

So, with jPDL, the path that your users can follow is represented by a finite graph, with well defined transitions from state to state (a state being either a page or decision).

Each time the jPDL/jBPM engine detects that a user took a path that is not defined in the graph, it triggers an Illegal navigation Exception.

If you provide some kind of escape door for your users (like a cancel button, or back to menu), you should end the pageflow when the user use it. The key point is to end the conversation : that will end the pageflow as well.

According to the doc, this is done by using <end-conversation> (in your .jpdl.xml file) or by calling an @End method. AFAIK, you could use a s:link to do that. But propagation="none" will not suffice: the conversation will not be propagated thought the link, but will still be active.

You need an s:link with propagation="end" (yes, it exists !)

Hope this helps,
Sylvain

Thanks guys... but this is not working well. If you use a s:link with

propagation=end

the conversation is ended but this still trigger the IllegalNavigation Exception.. If you click for second time in the link then works fine..

this is the correct behaviour?

Ariel

Looking the PageFlow class, I realized that this is a pending task (TODO). I think that in order to achieve the behaviour wanted, we must to comment the lines 133 to 137 :)

Here is the part of the code that we must comment:

         //now check that the restored view id matches what we expect
         //from the pageflow node
         //TODO: we need some way to disable this check, since users
         //      might want some adhoc nav in and out of a pageflow?
         String viewId = Pages.getViewId(facesContext);
         if ( !viewId.equals( getPage().getViewId() ) )
         {
            illegalNavigationError();
         }

There should be a way to end the pageflow without ending the conversation.

They should be considered different features.

Yes, that way exist..As Bernard or Sylvain said in the previous post you must write a s:link with

propagation=none

I think this will be fixed in the next release. Anyway, you can fix it following the post that I wrote above.

Ariel

Ariel Ludueña wrote on May 06, 2008 07:44 PM:
I think this will be fixed in the next release. Anyway, you can fix it following the post that I wrote above.

Is there a JIRA issue opened for this fix? I can't find one. How about a link or number? If there's no JIRA issue, I don't think it's on the radar to be fixed.

And, I don't see an explanation of a fix above for the case where one DOES want to end the conversation with propagation=end. Or, was the suggested fix for now to comment and recompile the code?

Thanks

There is no JIRA issue for this bug.. I thought that there was.. Can you report this?

The suggested fix is recompile the code :)

Comment the line that throw the illegalNavigationError() in the PageFlow class and recompile the code..

This is the fastest solution that we have..

Ariel

Ariel Ludueña wrote on May 08, 2008 03:14 PM:
There is no JIRA issue for this bug.. I thought that there was.. Can you report this?

I am not able to sign up to Seam Jira. Would anybody report this bug...? I've recompiled seam - it works now! Thanks!

Jan