Leon, Thanks for your thoughts.
I just convinced myself that thinking ActionForm as a part of Controller made most sense! Having said that, I'll be thinking more about your point of view. Regards, ATTA On Apr 1, 2005 4:59 AM, Leon Rosenberg <[EMAIL PROTECTED]> wrote: > On Fri, 2005-04-01 at 06:01 -0500, Ted Husted wrote: > > Well, you know, an ActionForm is what it is. :) > > > > On this list, most people will tell you it belongs to the View. > > > > To shorten Ted's post: > > This depends on your viewpoint. Inside the presentation layer it's 100% > the model. If you are talking about the presentation layer, refer to > ActionForm as Model. > > If you are talking about the system architecture, the whole presentation > layer is a view on the business layer. In this case ActionForm is part > of the view. > > regards > Leon > > > Other frameworks with similar architectural members call gizmos like > > ActionForms the "Model". Why? Because in classic MVC, the View > > subscribes to the Model, most often as an Observer. In a conventional > > Model 2 application, the View acquires data from the servlet contexts > > --- meaning the servlet contexts become the M in MVC. The JSP Tags > > "observe" critters like the ActionForm in the servlet contexts, hence, > > the argument would go, it's part of the Model. Snagging data from the > > contexts is not quite the Observer pattern, but it does have the same > > effect. > > > > Of course, since most, or all, of that data actually comes from a > > database, a lot of people tend to think of the database as the Model. > > And, in the big picture, the database usually is the one-true Model. > > But from the narrow perspective of Model-2 MVC, the JavaBeans we stuff > > into the servlet contexts do become, for all intents and purposes, the > > Model. > > > > One way to think of it is that our Views aren't designed to gaze upon > > the Model directly. So, the Controller creates a specialized form of > > the Model and places that chunk in the servlet context, where the > > Views can see it. From the View's perspective, the dynamic data in the > > servlet contexts is the Model. (Even though we know it's just a > > runtime snapshot of one sliver of the most-high database Model.) > > > > As to ActionForms in particular, personally, I consider everything in > > the Struts core (Action package) to be part of our Controller layer. > > The taglibs are our View, but the rest, including the ActionForm, is > > part of the Controller. The Controller simply shares the ActionForm > > with the View by putting it the Servlet context (so it becomes part of > > the Model as observed by the View). > > > > Of course, in the end, it doesn't really matter. The ActionForm is > > what the ActionForm is. The one thing it is not, is a business object. > > The Controller creates it from the request, and it bounces around > > between the Action and the JSP Tags (or other View Tools). But, it > > should *never* go past the Action into another layer. > > > > Aside from that key best practice -- the ActionForm should never go > > past the Action into another layer -- we might as well be discussing > > how many angels can dance on the head of a pin :) > > > > -Ted. > > > > On Mar 31, 2005 11:40 PM, atta-ur rehman <[EMAIL PROTECTED]> wrote: > > > Dea all, > > > > > > I'm sure I've seen this topic before! Just can't remember where and > > > google won't help either! Can anybody please explain which MVC layer > > > form belongs? > > > > > > TIA. > > > > > > ATTA > > > > --------------------------------------------------------------------- > > To unsubscribe, e-mail: [EMAIL PROTECTED] > > For additional commands, e-mail: [EMAIL PROTECTED] > > > > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: [EMAIL PROTECTED] > For additional commands, e-mail: [EMAIL PROTECTED] > > --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
