JSP functions and Java Bean methods

[lisa.lipsky]

Hi all,

I'm new to jsp and I have a question that I couldn't find an explanation for.
I want to know why most functions are written inside Java Beans instead of JSP pages.
I know this may sound like a silly question but if I can have clarification to my confusion, I'm entirely grateful.

Regards,
Lisa

[dswastik]

JSP should be primarily used for the presentation purpose. We should avoid writing our business logic, data access logic etc. inside jsp pages, rather we should put them in java classes. Moreover if you look on this also makes our code modular. If you have to make any changes in business logic or data access logic you dont need to do any thing in the jsp page, and on the contrary if you have to make some changes in the presentation part you will just make changes in the jsp page, you dont have to do any thing with the java classes.

[lisa.lipsky]

What if I write the inside one jsp, for example logic.jsp and has all my other jsp pages include logic.jsp? Is this advisable?

[dswastik]

No. Because as per MVC-II what you mostly follow in web application these days, three different things had different usage. Model->Bean classes,other helper classes
View->output what the user gets (Generated through jsp) and controller->Servlet.

[lisa.lipsky]

OK. Now I know why most business logics are written in Bean. Thanks.