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Here I'd like to give some design option and my thinkings of this project. Thank you for your comment.
Wiki Markup Since valves have different levels, such as server level, engine level, host level, context level. And there are several places for the configuration: server.xml, web.xml. For server level, both server.xml and web.xml is suitable, since both of them are some kind of global. For engine and host level, I think server.xml is much more suitable. And we could also use "$CATALINA_BASE/conf/\[enginename\]/engine-filters.default" for engine level filters, "$CATALINA_BASE/conf/\[enginename\]/\[hostname\]/host-filters.default" for host level filters and "$CATALINA_BASE/conf/\[enginename\]/\[hostname\]/context.xml.default" for context levelfilters. This is the options for configuration file location that I could think about. In my opinion, we could put all these configuration in server.xml for simplicity, but keep an eye on those "$CATALINA_BASE/conf/\[enginename\]/\[hostname\]/" path just like tomcat deal with context.xml.default now. \\
markt - Are Valves going to be removed completely?
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9. I've made a seperate wiki page for the configuration location of those newly added filters. Here is the link: http://wiki.apache.org/tomcat/SummerOfCode2009/LoadingFilterConfiguration
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