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The following page has been changed by MichaelJouravlev:
http://wiki.apache.org/struts/SAF1RoughSpots

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    1. '''SAF1 lifecycle'''  [MichaelJ] The lifecycle of SAF1 is quite simple, 
for a user's perspective it includes just reset/populate/validate functions. 
Consider to call all lifecycle functions explicitly from an action class, no 
more automatic population.
      * [FrankZ] I personally would not want to see the auto-population and 
validation and such go away.  I think them being declarative is a powerful 
notion.  I DO however agree that a developer should be able to turn them off 
declaratively and do it all manually.
+     * [MichaelJ] Considering to call lifecycle functions explicitly does not 
mean removing autopopulation from the next release :)
  
    1. '''Automatic validation'''  [MichaelJ] Deprecate automatic validation, 
newbies always stumble upon the fact that their action class is not called when 
validation fails. Instead, promote explicit validation.
      * [FrankZ] Definite -1 from me.  Again, I'm +1 to being able to turn it 
on and off, but I very much believe it should be there.  Perhaps there is some 
room for better logging in the cases you mention?
+     * [MichaelJ] Deprecating autovalidation does not mean removing that 
feature from the next release :) I hope you reconsider your "-1" or do you want 
me to remove "deprecate" word entirely? I think that without autovalidation 
things will be clearer: action class will always be called, and different error 
conditions with different targets can be supported.
  
    1. '''Input attribute'''  [MichaelJ] Deprecate "input" attribute of 
"action" tag in struts-config.xml. At least, rename it to "error" or something. 
A frequent misconception is to think that the lifecycle starts with displaying 
an "input" page, which is obviously not true.
      * [FrankZ] +0.  I don't disagree with you at all, and I think there are 
probably other things that could similarly be changed.  However, I think it is 
very important that anything done with SAF1 be evolutionary and take 
backwards-compatibility into consideration in a big way.  I think if you want 
revolution you go for SAF2 (a minor revolution in that it's theoretically still 
compatible) or Shale.
+     * [MichaelJ] Hey Frank, now ''you'' are writing me off the boat? ;) What 
if I want some revolution staying within SAF1 codebase?
  
    1. '''Form attribute'''  [MichaelJ] Add "form" attribute with the same 
meaning as "name" attribute; deprecate "name".
      * [FrankZ] +0.  Same comment as the above point.
+     * [MichaelJ] Again, "add" means add. It does not mean removing "name" in 
the next release.
  
    1. '''Differentiate forward from redirect in mappings'''  [MichaelJ] 
"forward" tag implements both forward and redirect, this is confusing. 
Implement two separate tags like "render" for forward and "transfer" for 
redirect. "forward" tag still can be kept for compatibility purposes.
      * [FrankZ] Hmm, I'm not sure how I feel about that.  Maybe simply adding 
a type attribute, ala Webwork, would do the trick?  "forward" or "redirect" as 
values?
+     * [MichaelJ] Check out this mapping from one of the users of Struts 
Dialogs 1.x (he uses Tiles too):
  
+ {{{
+ <component path = "/userCenter"
+            type = "com.acme.action.UserCenterAction"
+            form = "userCenterForm"
+            view = "page.userCenter">
+   <event name = "DIALOG-EVENT-CHANGE" handler = "onUpdate"/>
+   <event name = "DIALOG-EVENT-DELETE" handler = "onDelete"/>
+   <event name = "DIALOG-EVENT-SHOW-ORDERS" handler = "onShowOrders"/>
+   <event name = "DIALOG-EVENT-SHOW-PRICE-LIST" handler = "onShowPriceList"/>
+   <event name = "DIALOG-EVENT-SHOW-ORDER-DETAILS" handler = 
"onShowOrderDetails"/>
+ 
+   <transfer name = "SHOW-ORDERS" path = "/showOrders.do"/>
+   <transfer name = "SHOW-PRICE-LIST" path = "/showPriceList.do"/>
+   <transfer name = "SHOW-ORDER-DETAILS" path = "/showOrderDetails.do"/>
+ 
+   <render name = "ON-CC-DIALOG" path = "page.CCDialog"/>
+   <render name = "ON-GET-DELIVERY-CONFIRMATION" path = 
"/jsp/deliveryConfirmation.jsp"/>
+ </component> 
+ }}}
+ 
+ This mapping use new format for action mapping. "component" is essentially 
"action" with different defaults and some new elements. This is 1:1 
correspondence between mapping and action class. Same action class handles 
input phase as well as render phase (I saw your remark about 
Redirect-After-Post, here it is, implemented).
+ 
-   1. '''DispatchActions'''  [MichaelJ] Having that many dispatching actions 
in the distro, all of them but !EventDispatchAction and more generic 
EventActionDispatcher should be deprecated.
+   1. '''!DispatchActions'''  [MichaelJ] Having that many dispatching actions 
in the distro, all of them but !EventDispatchAction and more generic 
EventActionDispatcher should be deprecated.
  
    1. '''Tiles improvements'''  [MichaelJ] Improve Tiles to support real 
components, that can be fully independent of composite page, can process user 
input, and can render themselves.
  
    1. '''Per-request Action instantiation'''  [FrankZ] Actions should be 
instantiated for each request, therefore removing the thread safety concerns 
that exist today.
+     * [MichaelJ] +0. Not sure that this bothers me anymore :)
  
    1. '''Pure POJO !ActionForms'''  [FrankZ] An !ActionForm should not need to 
extend !ActionForm.  The framework would have to be smart enough to not call 
validate() and such in that case.  This would allow for the Action to be the 
!ActionForm as well, and this is really the underlying goal because many people 
view them being separate as a rough spot.
+     * [MichaelJ] Definite +1
  
    1. '''Built-in AJAX support'''  [FrankZ] I am not entirely sure what the 
best form for this is, although I believe the !AjaxTags paradigm still has a 
great deal of merit.  In any case, in today's world, not offering some degree 
of AJAX out of the box is probably a rough spot for many.
+     * [MichaelJ] I believe that I can combine JSP Controls Tag Library with 
Tiles, building both a real component subframework on top of Struts, as well as 
built-in Ajax features (actually, AHAH. It is coarse-grained in-place update of 
a component within a composite page. Therefore, I believe that it can coexist 
nicely with more finegrained approach of !AjaxTags).
  
    1. '''Custom attributes on tags'''  [FrankZ] All Struts tags that render 
HTML should allow for arbitrary attributes.  I again propose a "specCompliant" 
attribute on the <html:html> tag.  When true, no arbitrary attributes are 
allowed (this would be the default if the attribute is not present).  If false, 
any attribute can be added.  This has been a hassle for me a couple of times 
where I wanted to store some custom information on a tag for client-side 
purposes.
  
@@ -40, +70 @@

    1. '''!ThreadLocal !ActionContext''' [FrankZ] Yes, I think this is one 
place we should flat-out rip off Webwork :)  Backwards-compatibility would have 
to be considered, but I'd like Actions to have to deal with a single object, 
and for that object to be accessible via the !ThreadLocal mechanism.  This 
should also open the door for POJO Actions.
  
    1. '''Built-in support for RAP (Redirect After Post) pattern''' [FrankZ] 
I'm not sure how best to accomplish this, but this should be a very easy thing 
for a developer to do, the framework should do any required heavy lifting.  
Again, not so much a rough spot as it is something I think a lot of people 
would appreciate.
+     * [MichaelJ] Redirect-After-Post is fully implemented in Struts Dialogs 
1.x (last version is 1.24). After Struts 1.2.9 got better dispatch action, I 
stopped advertising Struts Dialogs project, but it is still valuable in terms 
of samples. Check it out. !EventDispatchAction can implement 
Redirect-After-Post as well, Paul and I spent quite some time discussing how 
!EventDispatchAction can be used for both input and render phases.
  
    1. '''Pre and post-processing abilities''' [FrankZ] A developer should be 
able to specify a class and method to call before and after an Action executes, 
on a per-mapping basis.  This should be independant of modifying a chain.  
Should just amount to adding the appropriate config file changes and two 
commands to the default chain.  This is for handling things like common setup 
of view-type Actions, etc.
+     * [MichaelJ] +0. I prefer having 1:1 correspondence between mapping and 
action class. With autopopulation out of the way, I can call whatever I want 
right in the beginning and at the end of execute() method. Same thing, but 
simpler, I think.
  
    1. '''MAYBE roll StrutsWS into Struts''' [FrankZ] Heck, I'm not even sure 
*I* would +1 this idea!  Might be worth considering at least.
  
@@ -60, +92 @@

  
    1. '''Webresource-centered approach'''  [MichaelJ] Up until now SAF1 best 
practices center around a View, usually a JSP page. Instead, best practices 
should teach the webresource-centered approach.
      * [FrankZ] Speaking for myself, I would need to see a good definition of 
this approach before I was +/- on it.  I have never seen a clear explanation 
that made me say "oh yeah, I see, that's better!"
+     * [MichaelJ] Check out DataEntryForm. Well, it uses dispatching action 
and session-scoped form, but if you look at it from 10000 ft, it gives the idea 
of what web resource is about. Basically, it is one-two actions, one form and 
one or more JSPs. A resource does NEVER forwards to a JSP page that does not 
belong to the resource. In the best case we can have nice and simple 1:M 
relationship between action and JSPs.
  
    1. '''Dispatch-type actions should be more front-and-center'''  [MichaelJ] 
Dispatch-action style request processing should become a cornerstone technique 
instead of "yet another way of doing things". It works especially well in data 
entry form processing or menu processing. See DataEntryForm.
      * [FrankZ] As an oft-stated opponent, GENERALLY, of Dispatch-type 
Actions, I wouldn't be thrilled with this being sold as a "best practice".  I 
would have no problem with it being described in more detail and the pluses and 
minuses stated for people to be able to make a more informed decision either 
way.
+     * [MichaelJ] If you stop thinking in JSP pages, and start thinking in 
terms of resources that accept commands, then dispatch action comes as a 
natural fit.
  
    1. '''Preference for session-scoped !ActionForms'''  [MichaelJ] Best 
practices should explain that there is nothing wrong in having session-scoped 
action forms. Best practices should teach how to build stateful web resources.
      * [FrankZ] -1.  Saying there is "nothing wrong" with it, I do not believe 
is true.  Speaking as someone who works all day in a large distributed 
enterprise environment, I am very well aware of the pitfalls of storing things 
in session and in letting session get too big.  I'm not saying I never store 
anything in session, of course I do! :)  But I think people need to know the 
positives and negatives of doing so and decide what is appropriate in a given 
use case rather than being told this or that is a "best practice".
+     * [MichaelJ] My original wording did not have "preference". What I am 
saying is that session-scoped forms should not be a taboo, and their benefits 
should be cleanly explained. Would you reconsider your "-1"?
  
    1. '''Building stateful components'''  [MichaelJ] It is possible to build 
stateful and independent web components with SAF1. Best practices should teach 
how to do that.
  
    1. '''!ActionForm as true I/O buffer'''  [MichaelJ] !ActionForm should be 
used as I/O buffer instead of simply collecting user input from request.
      * [FrankZ] Could you explain this further?  I'm not at all clear on what 
you mean.
+     * [MichaelJ] This is that 60% of Struts users do. I guess you do it as 
well. You have actionform associated with input action. You submit a form, 
actionform is populated. In case of error or whatnot you render the same JSP 
page a pull the data from the actionform, it is already there, saved for you by 
Struts. I use this all the time for data entry use case, but this does not seem 
to be an officially endorsed practice.
  
    1. '''Use of nested properties'''  [MichaelJ] Emphasize using of nested 
properties, using business objects as nested properties, using dynaforms 
holding business objects.
  

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