Check all your Maven (or equivalent) dependencies and make sure that you – or most likely another dependency – are not pulling in a pre-3.1 version of the javax.servlet / servlet-api that may be taking precedence over what’s in your Tomcat 8. If you’ve manually deployed, make sure you haven’t manually copied any servlet-api JARs into Tomcat itself.
See: https://stackoverflow.com/a/26232535/954442