Very urgent: call servlet from JSP

Question

Hello,
I'm facing a problem in invoking a servlet from a JSP having the JSF components.
The application has a text field to implement ajax for search functionality in the database .I have written a servlet to make the database connection and fire the querry.
Ajax implementation in a js file is called on every keyup event in the jsp file,and
a call is given to the servlet from the ajax methode.
The function in the js file is as follows:-
function getPersonByFirstNameXML( firstName ) {
    if (!firstName) {
        clearPersonByFirstNameXML();
    } else {   
        var url = BASE_URL + "/servlet/get_PersonsXML";
        alert(url);
        return new AJAXRequest("post", url, "firstName=" + encode(firstName), processGetPersonByFirstNameXML);
}Im getting the myAJAX.status value as 500.
I think I'm not able to access the servlet properly.
what changes do i need to make in the we.xml file ?
and what should be the url to be passed.
Please provide me a sloution to the above problem as it is very urgent else if anybody is aware of a readymade JSF componet with search functionality freely available please let me know.
PS:
The sample application named RedirectionExample which makes use of a servlet and would be of help to you. You can find the tutorial on the following page:
http://developers.sun.com/prodtech/javatools/jscreator/reference/codesamples/sampleapps.html
is not available as stated in some of the suggestions by Author: mayagiri
Thanks for any help.
Abhi

Answer 1

the status 500 generally means either HTTP server internal error or that execution of CGI script or servlet aborted with error.
It can be reasonably supposed that the request reaches the servlet, ie. that "url" value points to some existing servlet, otherwise most probably the status value would be 404.
To test that the servlet is working i'd try to access it using some simple html page with form like this (with {BASE_URL} replaced by real value):
<form method=post action={BASE_URL}/servlet/get_PersonsXML>
<input type=text name=firstName>
<input type=Submit>
</form>