I second Play Framework. Have used it and Scala is a very nice language to learn. If I had invested in so much into the JVM, Play Framework would be it. But, if it's just a simple CRUD app, and if you had a choice, I'd recommend you to give Ruby on Rails a try. Hope this helps!
The last version comes with Slick integration which brings Ling-for-Sql style persistency to the JVM. In combination with support for Postgress JSON persistency that makes for a great fast prototyping stack.