I'm interested in this mapper you talked about, thanks,
btw: What is the difference between this one and the one on Ted Husted's? Are you talking about Mapco? Sandeep --- "Sobkowski, Andrej" <[EMAIL PROTECTED]> wrote: > Hello, > > we're working on a quite large project with J2EE > (including EJBs) and we're > using Struts (we're still in the early phases). To > design a "clean" > application, I've defined different "object > conversions": > * Request phase > - the ActionForm is converted to a Value Object > - the Value Object is passed to the EJBs > * Response phase > - the EJBs return one ore more Value Objects > - the Value Object(s) is (are) converted back to > ActionForms. > > I think it's a good approach, but: > - my ActionForm and Value Objects have an almost > identical interface. The > main difference is that the ActionForm instance > variables are always of type > String while for the Value Object have "final > types" information (Date, > Integer, whatever) > - the conversion "ActionForm to VO" and back is > slowing down the performance > as my EJBs often return hundreds of VOs (each one to > be converted to an > ActionForm). > I know this can be improved by using paging > (Page-by-Page iterator) on both > the back-end and the front-end; furthermore, I've > written a small "mapper" > that uses extensively the Reflection API to > automatically perform the > mapping and this probably has an impact on the > overall performance. > > My question is: what are the best practices for this > type of issues? Does > anybody have the same problems? Should I reduce the > level of abstraction > between the layers? > > Thank you! > > Andrej > > PS. if you're interested, I can share the simple > mapper. It's a very small > mapper (less than 15k) that works fine with my app. > It's waaaaaaay less > complete than the mapper on Ted Husted's site but... > > -----Original Message----- > From: Jon.Ridgway [mailto:[EMAIL PROTECTED]] > Sent: Thursday, November 22, 2001 12:10 PM > To: 'Struts Users Mailing List' > Subject: RE: design question > > > > > -----Original Message----- > From: M`ris Orbid`ns [mailto:[EMAIL PROTECTED]] > Sent: 22 November 2001 16:54 > To: Struts-list (E-mail) > Subject: design question > > Hello > > I have several questions about design, "best > practises": > > 1) Where to store client's profile information > (like login name) ? > session or system state bean ? > > Use the HttpSession. But be aware that you should > put as little as possible > into the session. Large sessions do not work well in > a cluster. > > 2) How to create and use a system state bean ? > > System state bean should be in scope "session", > shouldnt it ? > > Again put as little as possible in the session and > avoid statefull session > beans. If you must put a bean in the session, make > it as small as possible, > ideally it would just hold key info that can be used > to request beans at > request level when needed. This is a trade off > between performance and > scalability. > > 3) Where to put business logic (where I invoke JDBC) > ? > Should business logic class be a bean ? > > If you have an app server business logic should go > into a stateless session > bean (BusinessService), which is invoked (via a > BusinessDelegate) from a > struts Action class. If you are not using EJBs then > the Action class should > still invoke a business delegate, but the delegate > would simply create a > normal Java bean to act as the Business Service. The > business service > (Stateless EJB or Java Bean) should delegate to > another class to access a > datasource. If your are using EJBs this should be a > CMP or BMP+DAO depending > on your app server (EJB 2 compliant consider CMP, > else try CMP if supported > but be prepared to subclass to a BMP+DAO at a later > date). > > thanx in advance > Maris Orbidans > > > Jon Ridgway. > > -- > To unsubscribe, e-mail: > <mailto:[EMAIL PROTECTED]> > For additional commands, e-mail: > <mailto:[EMAIL PROTECTED]> > __________________________________________________ Do You Yahoo!? Yahoo! GeoCities - quick and easy web site hosting, just $8.95/month. http://geocities.yahoo.com/ps/info1 -- To unsubscribe, e-mail: <mailto:[EMAIL PROTECTED]> For additional commands, e-mail: <mailto:[EMAIL PROTECTED]>
