I’ve been writing servlets and filters for years and it is something that has always irked me a little – the checking and casting of ServletRequest and ServletResponse parameters to HttpServletRequest and HttpServletResponse, particularly with filters as there is no standard HttpFilter base class to do this for you – unlike servlets.
The question is – when would you ever see anything other that HttpServletRequest/HttpServletResponse being passed to your servlet/filter and what should you do if you do?
In some yet-to-be-realized world where there are other servlet types besides HttpServlets.