A person said to me that Filters (Servlet 2.3) are not portable, he said that some containers have no support for them. I´m not agreed, since Filter is part of the Servlet API and is so much used to cache, debugging, authentication and so on ...
Somebody knows about this? There is a container that not supports the Filter API ?
There are plenty of organizations that are still using older, Servlet 2.2- servers (like Websphere 4), so filters won't work on those servers.
I don't know of any Servlet 2.3 compliant server that does not support filters, though. In fact, by definition, it can't be Servlet 2.3 compliant if it doesn't.