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Why no HttpServletReq on doFilter?

Max Tomlinson
Ranch Hand

Joined: Jul 17, 2001
Posts: 365
Seems odd (to me anyway) that doFilter would not take HttpServletRequest as input...aren't most filters going to apply to Http?
--->public void doFilter(
ServletRequest req,
ServletResponse resp,
FilterChain chain)
throws ServletException, IOException {

So if, for example, to get pathInfo, I have test for instanceof HttpServletRequest, then cast to it, just to get some basic info.
Or am I missing something?
Steve Leach
Ranch Hand

Joined: Sep 24, 2003
Posts: 46
Filters aren't Http specific. If you *know* that you are only going to get HttpServletRequests (which is reasonable) then you are safe to cast without checking.
Max Tomlinson
Ranch Hand

Joined: Jul 17, 2001
Posts: 365
OK, thanks.
Where would I want to use a non-http filter?
I agree. Here's the link:
subject: Why no HttpServletReq on doFilter?
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