This is an excerpt from a blog post by Gordon Dickens, Chariot Architect and Trainer (via Technophile Blog)
After several iterations of Grails, we have to go to 17 (seventeen) pages to see all the validation constraints? I wanted to see them on one page.
Grails 1.3.5 – Validation Constraints
blank – To validate that a String value is not blank.
creditCard – To validate that a String value is a valid credit card number.
email – To validate that a String value is a valid email address.