It is not possible to use a custom tag for client-side validation. Any custom tags, along with any other JSP elements on your page, are executed to format the page before it is sent to the browser. So by the time your user is entering values into the input elements, these elements have long gone out of scope.
So, I want these tags to allow for my model update only if the date validation succeeds (like in JSF architecture) else throw an error
As I'm not in a position to adopt JSF techonolgy in my application, I'm in the lookout for such components
Re-read my first response. Custom tag technology cannot help you here. Anything on the page is evaluated to create the page to send to the client. You should be handling the server-side validation in the servlet to which the form is submitted.