Frank, I like your M+V+C channeling examples!
Thanks. ATTA On Apr 1, 2005 5:53 AM, Frank W. Zammetti <[EMAIL PROTECTED]> wrote: > "...we might as well be discussing how many angels can dance on the head > of a pin" > > 639. 704 if they all go to LA Weight Loss for 3 months. But either way > that assumes they haven't been drinking, otherwise they won't be able to > keep their balance long enough to count. I believe this research was > done at AMD development labs in coming up with the Athlon 64. But I > couldn't find a reference online. > > (Ahem. There goes my standup career.) > > About the ActionForms... I don't personally consider them part of either > layer. Tangentially, the same goes for Value Objects. They straddle > the line between two layers in my mind. They are the channel through > which the view communicates with the control layer, and Value Objects > are the channel through which the control layer communicates with the > model. Hence, I don't consider them part of either layer. Perhaps we > should stop calling it MVC and instead call it M+V+C, with the + signs > indicating those channels. :) > > Perhaps that's a politician's answer, avoid giving a real answer to a > sticky question :) but I actually feel like that fits the evidence, so > to speak. Depends on what the definition of "is" is I guess :) > > Frank > > 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. > > > > 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] > > > > > > > > > > > > -- > Frank W. Zammetti > Founder and Chief Software Architect > Omnytex Technologies > http://www.omnytex.com > > --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
