How can we redirect the servlet response with success/failure message to same page using sling selectors

Hi,

We have implemented a form using OOTB forms tool kit. When we submit the form, an email is triggered to send the form data in that. So, on successful submission, we redirect to success page or else we redirect to a failure page.

Now, we don't want the redirect to happen but stay in the same page but show the success/failure message to user.

How can we achieve this?

I'm not looking at using Ajax for getting the success/failure message.

How can we use sling selectors to achieve this?