ActionMailer sending mass emails,Suggestion for validation

Hi all,

I’ve used below link to send mass emails to people.I am able to send
using the same code without any issues.

Now,Is that i need to validate Subject,Recipient,Message text boxes.Can
you please suggest me how this can be achieved.As i am very new to rails
and i beleive ActionRecord cannot be used here as we are using
ActionMailer for sending mass emails.

Appreciate your quick response with some example to do or any steps.