AJAX call to PageFlow's actions and response

Question

Hi,
in my portlet, I need to do ajax calls for some actions. This works fine but I have a problem with the response. I want to put in the response only a message to be shown to the user (for example "Update successful" or "Error !!"), but WebLogic Portal write all the content of the page, even if I do not define any forward and I return null in my action.
@Jpf.Action()
protected Forward myAction() throws IOException
// action content
return null;
How can I tell WebLogic Portal to write nothing in the response when I return null ?

Answer 1

a) The only way I found to have an URL to an action is to put a <netui:anchor tagId="link" action="updateOrderFavori" value="" style="display:none;" /> tag and retrieve the generated URL in javascript (portlet:actionURL throwing IllegalStateException But I know it's not very clean. Moreover, as you say, the generated URL is a portal URL, not a URL directly to an action. How can I do that ? Is there an API to generate such an URL (like PageURL for a page URL) ?
b) I am not sure that the Portal AJAX features suit my needs because I don't want the whole porltet to have an AJAX behavior but only some actions. Can I do this with Portal AJAX features ?
Regards
Thomas