问题
Does the FacesServlet in JSF 2.0 support the servlet 3.0 async features?
回答1:
No, with the simple reason that JSF 2.0 is designed with Servlet 2.5 in mind.
JSF 2.1 in turn is however designed with Servlet 3.0 in mind, but it does not utilize the new async features, perhaps with the simple reason being that there's just no need for it. The closest what you can get is ajax poll/push provided by 3rd party component libraries like RichFaces, PrimeFaces or IceFaces.
来源：https://stackoverflow.com/questions/6679790/facesservlet-servlet-3-0-async-support