What major considerations are there in choosing a solution to implement
object to rdb mapping?
Aaron
-----Original Message-----
From: erik morton [mailto:[EMAIL PROTECTED]]
Sent: Tuesday, April 24, 2001 12:21 PM
To: [EMAIL PROTECTED]
Subject: Re: Developing an N-tier system
The biggest advantage that I can see for using JSPs instead of Servlets for
the
"workflow" layer is Rapid App Development - that's it. As a previous reader
pointed
out, Servlets are true objects where JSPs are really just a temporary
concept that
are translated into actual servlets at deploy/runtime. On the other hand, if
you
place ALL of your business logic inside beans than I see little need for
servlets.
But you must put ALL of the logic in the beans - I don't want to see a
single IF
statement in those JSP pages and don't even think about accessing the
database :-).
I said it before and I will say it again: spend time working on your
persistence
model. The truly robust systems that I have seen have persistence models
where you
can change the data model all you want and you never recompile your code. As
a rule
of thumb, we never embed SQL in the middle tier.
You can call me Captain Obvious if you want.
some links:
http://www.ambysoft.com/
http://www.castor.org/
Aaron O'Hara wrote:
> All,
>
> I'm designing an N-tier application and would like some feedback,
comments,
> notes from the field. I have tried to layer my design as follows:
>
> JSP/HTML - presentation layer
> Non-Gui JSP - workflow layer
> Scope Beans (page, request, session, application) - business logic
> Psuedo Entity Beans - persistence layer
> DB API - database services
>
> In the presentation layer, I either present information to the user or
> receive form information. All the form submissions go to the workflow
layer
> which calls the necessary business logic beans to determine what should
> happen next. The business logic beans retreive or save data using the
> psuedo entity beans. (I say psuedo because this in not a EJB entity bean,
> but an object that maps to a corresponding table in a database). All the
> entity beans perform their database operations via a singleton class, the
DB
> API.
>
> I'm looking for a critique or comments from people about the design I've
> adopted and implemented.
>
> Aaron
>
>
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> Some relevant FAQs on JSP/Servlets can be found at:
>
> http://java.sun.com/products/jsp/faq.html
> http://www.esperanto.org.nz/jsp/jspfaq.html
> http://www.jguru.com/jguru/faq/faqpage.jsp?name=JSP
> http://www.jguru.com/jguru/faq/faqpage.jsp?name=Servlets
--
Erik I Morton
Software Developer
------------------
CommerceHub
http://www.commercehub.com
518-886-0704
21 Corporate Drive
Clifton Park, NY 12065
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To unsubscribe: mailto [EMAIL PROTECTED] with body: "signoff
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Some relevant FAQs on JSP/Servlets can be found at:
http://java.sun.com/products/jsp/faq.html
http://www.esperanto.org.nz/jsp/jspfaq.html
http://www.jguru.com/jguru/faq/faqpage.jsp?name=JSP
http://www.jguru.com/jguru/faq/faqpage.jsp?name=Servlets
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To unsubscribe: mailto [EMAIL PROTECTED] with body: "signoff JSP-INTEREST".
For digest: mailto [EMAIL PROTECTED] with body: "set JSP-INTEREST DIGEST".
Some relevant FAQs on JSP/Servlets can be found at:
http://java.sun.com/products/jsp/faq.html
http://www.esperanto.org.nz/jsp/jspfaq.html
http://www.jguru.com/jguru/faq/faqpage.jsp?name=JSP
http://www.jguru.com/jguru/faq/faqpage.jsp?name=Servlets
