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Why the Filter is mapped with /* and how to configure explicit exclusions (since 2.1.7)
In the example above we've mapped the Struts 2 dispatcher to /*, so Struts 2 has a crack at all incoming requests. This is because Struts 2 serves static content from its jar files, including Dojo JavaScript files (if using S2.0, or the Dojo plugin in S2.1+) and FreeMarker templates for the Struts 2 tags that produce HTML.
If we change the filter mapping to something else, for example /*.html, we must take this in to account and extract the content that would normally be served from the Struts 2 jar files, or some other solution.
Since Struts 2.1.7, you are able to provide a comma seperated list of patterns for which when matching against the
request URL the Filter will just pass by. This is done via the configuration option struts.action.excludePattern, for example in your struts.xml
<struts>
<constant name="struts.action.excludePattern" value=".*unfiltered.*,.*\\.nofilter"/>
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