My reasons are as follows. I do not know if they are right or wrong, but would appreciate comments.
1. Consistency. All of the dynamic data that is presented in a jsp is via bean:write tags or scriptlets which access a value object. I think pre-populating or initializing a form should be no different. 2. Breaks MVC(IMHO). Action is a controller component. Initialization of forms is a presentation issue. 3. Additional code. A value object is generated anyway by the DAO(which you use to get the data). If you use the action for initialization, all you are doing is copying the data into the form bean. It ensures clean separation of data when you do it the other way around (i.e copying data from form bean to value object even if they are similar) because you do not want the rest of your code to know about action forms etc which are html specific. But it does not make sense (to me) to copy pure java objects/value beans into identical form beans just for pre-population. 4. Easier debugging. If your value is populated wrong, you can look at the jsp to figure out which values are being written from which bean. If you do init in the action, you have to debug java code to find out presentation issues especially for things like multiple selects of dropdowns etc. Again, I am not saying init in the action is wrong. But I saw a lot of emails saying that it is the right thing to do without giving any reason. For the above mentioned reasons, I opted not to do the init in the action. I am trying to understand why this approach is recommended over the other one? What have I missed? TIA, JC -----Original Message----- From: Barr, Scott [IBM GSA] [mailto:[EMAIL PROTECTED]] Sent: Tuesday, February 19, 2002 6:45 PM To: 'Struts Users Mailing List' Subject: RE: How do I init a Form bean via business logic? Hi JC If the data is dynamic, and we are talking about web apps here, why not populate it in the action? The form is a view component, and I don't give it any more 'smarts' than is possible. This as a neat way of separating the layers your application, one of the benefits of clean MVC design Scott > -----Original Message----- > From: Jakkampudi, ChandraseKhar [SMTP:[EMAIL PROTECTED]] > Sent: Wednesday, February 20, 2002 10:59 AM > To: 'Struts Users Mailing List' > Subject: RE: How do I init a Form bean via business logic? > > Why should pre-populating a form be done in the preceding action? When you > want to display some dynamic info. say in a table you put a value bean in > the request or session and use bean:write etc to display. Why should the > same not apply to form beans? Why not use the value attribute of the the > html tag libraries to pre-populate the data? I have seen posts saying it > should not be done this way but no reasons are given. > > What I mean is: > <html:text property="data" value="<%=bean.getData()%>"/> is a valid way to > populate the form (as long as the bean is in request scope and not session > or application scope) > > why is the above not recommended or preferred? > > -- To unsubscribe, e-mail: <mailto:[EMAIL PROTECTED]> For additional commands, e-mail: <mailto:[EMAIL PROTECTED]> -- To unsubscribe, e-mail: <mailto:[EMAIL PROTECTED]> For additional commands, e-mail: <mailto:[EMAIL PROTECTED]>
