Here is a survey from 2012(note: the article is from 2014) that has Spring nearly twice as popular as Struts 2. Here is another using Google Trends that show Spring has substantially more people searching for it. If you look at the forums here you'll see that the Spring forum gets a lot more traffic than the Struts forum.
Does that mean Spring is the best framework for your application? That's for you to decide. As a matter of fact the first report I linked tries to answer that question and comes up with Vaadin, Grails and Play as their first, second and third choices and I haven't seen any of those in the wild. Looking in the forums here, only Grails has a mention (on the Groovy forum). A glance at our Other Frameworks forum shows two topics for Play and none for Vaadin.