call servlet from javascript

we need an implementation, to call servlet, from java script, servlet has to return back value to javascript from servlet has called.

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David H.H.LeeCommented:
Hi vittalmareddy,
Perhaps you can check this previous solved solution:

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Ajax is what you need:

There are many implementatios available, a short list would be:

- Prototype:
- Scriptaculous:
- Dojo:

There are many others, but I think any of the later would do the work. Of course you can also do it manually, coding all of it, but why reinvent the wheel when it's already available for free?
jQuery is a very good javascript library which provides several APIs along with post request from javascript...

Attached is a very simple example. (put all files in one directory and open jspost.html)

for more info check
This is exactly what you need.

I prefered to use some code earlier in my project.

The calling AJAX method

function ajaxFunction() {
  if(xmlhttp) {
   var txtname = document.getElementById("txtname");"POST","getname",true); //getname will be the servlet name
    xmlhttp.onreadystatechange  = handleServerResponse;
    xmlhttp.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');
    xmlhttp.send("txtname=" + txtname.value); //Posting txtname to Servlet

Inside the Servlet getname

  if(request.getParameter("txtname") != null) {
   name = request.getParameter("txtname");
                else {
                       name = "";
           out.println("You have successfully made Ajax Call:" + name);

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vittalmareddyAuthor Commented:
this is what i was looking for
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Java EE

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