His objection might have been that sendRedirect(...) makes the client have to make another http request to the server. include(...) or forward(...) would behave similarly, but the client wouldn't even know they had occurred behind the scenes.
Servlet filters are also a nice place to put this type of behaviour especially if say more than one page had blocked access on fridays. That way you put the logic in the filter and you don't have to change the servlet code.
steve -
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