Return Ajax response to JSP

[Balamurugan Balakrishnan]

Hi all,

I have written a code in Ajax, from that i will get some responseXML from the server, get the value from the xml and i need to return the value to JSP while i getting the value in jsp it's Empty. please advice


Thanks in advance,
Bala...

[Bear Bibeault]

By the time an Ajax call can be initiated, the HTML page has been sent to the browser and the fact that the page was generated by a JSP is moot.

So what are you really trying to accomplish?

[Balamurugan Balakrishnan]

need to return Ajax response. have a look at this

  var xmlhttp = AjaxAPI.getXMLHttpRequest();
	xmlhttp.open("POST", url, "true");
	xmlhttp.send(null);
	xmlhttp.onreadystatechange = function(){
		if (xmlhttp.readyState == 4){
			if (xmlhttp.status == 200)
			{
				var x = xmlhttp.responseXML.getElementsByTagName('attribute');
				for(var i=0; i<x.length; i++){
					var name = x[i].getAttribute("name");
					var value = x[i].getAttribute("value");
					if(name == "Error"){
						alert(value);
					}
					else{
						return value;
					}
				}
			}
			else
			{
				alert("Probs");
			}
		}  

[David Newton]

Please UseCodeTags when posting code or configuration. Unformatted code and configuration is very difficult to read. You can edit your post to include them by using the button.

[David Newton]

What are you returning the value *from* in the above code?

[Balamurugan Balakrishnan]

some message...

[Bear Bibeault]

Balamurugan Balakrishnan wrote:some message...

If you are going to be uncooperative, how are you to obtain any help?

[Balamurugan Balakrishnan]

I said that "i am going to return some message from the Ajax, and process it in JSP".


sorry if anything wrong!

[Bear Bibeault]

Please read this for more information.

The more relevant details you give, the better your chances of getting help.

[David Newton]

No, not what are you returning, what are you returning it *from*?

The code you posted has a return statement, but it's not inside a function, so is meaningless.

You need to *do* something with the message.

[Balamurugan Balakrishnan]

Just give an alert or confirm box with the message which return from the server. for that I need to pass the message to my JSP file.

[David Newton]

So do that in the function you've already written. I'm not sure what the issue is.

[Balamurugan Balakrishnan]

The issue is that the returned value was empty, it say undefined while alert the returned message.

[Milind Mahajan]

Is it that you are getting alert dialog box with message 'undefined'? If so, can you post the actual xml text that is being received in the function? May be that would help us understand the issue better.

-Milind

[Balamurugan Balakrishnan]

here is the XML that returns from the server.

<data>
      <attribute name="keyValue" value="Please enter proper number"/>
</data> 

[David Newton]

So... the message *isn't* empty?

[Balamurugan Balakrishnan]

but returning the value it's alert like "undefined".



This was i have got.

[Paul Clapham]

If the server is returning an XML document to the AJAX request, but your Javascript code which attempts to process that returned document is encountering an undefined value, then clearly there's something wrong with your Javascript code.

So have a look at that. You could even post some details here if you wanted to progress a little faster.

[Eric Pascarello]

Balamurugan Balakrishnan wrote:here is the XML that returns from the server.

<data>
      <attribute name="keyValue" value="Please enter proper number"/>
</data> 

That looks like invalid xml to me. Is that the entire document that is returned?

Eric

[Balamurugan Balakrishnan]

i have return the value to some other JSP from the Javascript mentioned above.

[Paul Clapham]

Balamurugan Balakrishnan wrote:i have return the value to some other JSP from the Javascript mentioned above.

Oh, I see. Problem solved then?

[Balamurugan Balakrishnan]

i have returned but in the JSP only It has been alert as "undefined"

[Paul Clapham]

No, that "undefined" has to be coming from Javascript. As you know, the JSP runs on the server and generates HTML, which in this case includes Javascript. Your problem is with that Javascript. As you also know, we haven't seen any of that Javascript code. Only you have. So carry on looking at it. Good luck!

[Milind Mahajan]

Comparing the xml and the earlier Javascript code that you posted, I think there might be a problem in the way attributes are being accessed by the JavaScript code. For example, this is how I would access the value of "name" attribute of the "attribute" tag:

  var name = x[i].childNodes[0].getAttribute("name");  

instead of

  var name = x[i].getAttribute("name");  

Hope this helps,
-Milind

[Balamurugan Balakrishnan]

thanks for all your responses. Still i have the problem.

[Eric Pascarello]

I think it is about time you sit down and learn how to debug. Figure out why it is not working. Use Firebug for Firefox and set break points. If you can not do that, start adding alerts and see what is going on.

Eric