Play is the closest - but it's nowhere near the maturity of Rails. One good strategy that I see a lot of companies adopt is to write a services layer in Java/Scala and then keep the front-end Rails app part light weight. This way, you get the benefits of a robust, type-checked backend and the flexibility of Rails for the strictly web related stuff like asset pipelines etc.

Of course, the downside is that you need to switch context between two languages. However, this has not bothered me in the past too much.