Is it possible to have a JSP/JSPX form to submit to a PHP file?
The PHP file will then be in charge of validation and database update. After that it will send a sort of response to the same JSP/JSPX form. Also this should be done in AJAX using jQuery.
How can I do that and what are the underlying concepts needed?
Thanks!
You don't need anything specific in your case. Just submit the form via Ajax using jQuery to the PHP page and process the result in JavaScript as well. All the code necessary for that will be client side in JavaScript and operate on the plain HTML generated by the JSP page. The only restriction/problem might be if these two pages run on different domains.