Using a Filter to serve a specific page?

I am using a class which implements Filter for my jsp stuff. It looks like this:

public class MyFilter implements Filter 
{
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) 
        throws IOException, ServletException 
    {
        request.getRequestDispatcher("mypage.jsp").forward(request, response); 
    }
}

So the target, "mypage.jsp",开发者_开发百科 is just sitting in my top-level directory. The filter works fine if I'm entering urls like:

http://www.mysite.com/foo
http://www.mysite.com/boo

but if I enter a trailing slash, I'll get a 404:

http://www.mysite.com/foo/
http://www.mysite.com/boo/

HTTP ERROR: 404
/foo/mypage.jsp

RequestURI=/foo/mypage.jsp

it seems if I enter the trailing slash, then the filter thinks I want it to look for mypage.jsp in subfolder foo or boo, but I really always want it to just find it at:

http://www.mysite.com/mypage.jsp

how can I do that?

Thank you

---

Make the request dispatcher path absolute - use "/mypage.jsp" rather than "mypage.jsp". The resource is then resolved from the root of the webapp context.