JSP -> servlet -> JSP

[sabah ammar]

Hi, I am working on learning JSP/Servlet. I need to know that how may i retrieve some data from servlet into JSP? as my servlet already is retrieving data from jsp.thank you.

[Ben Souther]

What do you mean by:

as my servlet already is retrieving data from jsp.

?

[sabah ammar]

ok.. from an html page i am submitting form action to servlet. where I am retreiving data thru sql. now I want to display the selected data in another JSP. I just need to know how to link servlet to a new JSP. hope i cleared my question.

[Stan James]

Does this describe what you're trying to do?

 
   Browser      Servlet        JSP        Request       Model
 ------------ ------------ ------------ ------------ ------------
 
      get page
      +------------>
                   get parameters
                   +------------------------->
                   get data
                   +-------------------------------------->
                   put data
                   +------------------------->
                   forwardTo
                   +------------>
                                get data
                                +------------>
      HTML
      <-------------------------+

I assumed we wanted to get some data from the server, and elaborated a bit with the call to get data from the model. It's common for the servlet to get something from the database (for example) and put the data on the request, then forward to the JSP which gets that data and merges it into the response HTML.

[Stan James]

Wow, you answered my question while I was typing! Now the bad news: I do this so rarely I don't have the answer to your question memorized. I'll be back in a few minutes after I dig up an example.

Ok, I'm back. Look at:

getServletContext().getRequestDispatcher( "some.jsp" ).forward( request, response );

[ June 12, 2005: Message edited by: Stan James ]

[Ben Souther]

You did.

You'll want to read up on the RequestDispatcher interface.

You'll also want to learn how to bind your objects to the various 'scoped' objects that are available to JSP pages.
Section 13.4 in this chapter is helpful in this regard:
http://csajsp-chapters.corewebprogramming.com/CSAJSP-Chapter13.pdf

If you would like to see all of this being done in a very simple example, look at SimpleMVC from http://simple.souther.us
[ June 12, 2005: Message edited by: Ben Souther ]

[Stan James]

Doesn't anybody have anything better to do on Sunday night besides type faster than me?

[Ben Souther]

Originally posted by Stan James:
Doesn't anybody have anything better to do on Sunday night besides type faster than me?

If I tried to type that ascii art UML sequence diagram I'd still be working on it and wouldn't look half as nice.

[sabah ammar]

good good... both of you keep it up :roll: I got my answer. thanks.

[Stan James]

I have a tool to make those diagrams, but last night I guess I forgot part of it was case sensitive. I sat for a few minutes scratching my head.