Sure they are using Java, through languages like Scala and Clojure both of which runs on the JVM, neither of which forces you to actually write in Java.
These days there is basically no reason to do webdevelopment in Java - even if you have legacy stuff lying around, JRuby or Scala will serve you much better and neither is that hard to learn and both will get you over Javas sever limitations (really, no anonymous functions? No Closures?)
These days there is basically no reason to do webdevelopment in Java - even if you have legacy stuff lying around, JRuby or Scala will serve you much better and neither is that hard to learn and both will get you over Javas sever limitations (really, no anonymous functions? No Closures?)