Why my filtering does not work for me and how to setup it to work?
There is my web.xml:
<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
<servlet>
<display-name>GameServlet</display-name>
<servlet-name>GameServlet</servlet-name>
<servlet-class>ajaxdemo.action.GameServlet</servlet-class>
<load-on-startup>0</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>GameServlet</servlet-name>
<url-pattern>/gameservlet</url-pattern>
</servlet-mapping>
<filter>
<filter-name>struts2</filter-name>
<filter-class>
org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter
</filter-class>
</filter>
<filter-mapping>
<filter-name>struts2</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
<welcome-file-list>
<welcome-file>index.jsp</welcome-file>
</welcome-file-list>
</web-app>
On this configuration GameServlet does not receive anything and web server reports that there are no action mapping for /gameservlet URL.
If I comment filter-mapping this servlet works fine by this URL.
How to get working Struts filters and servlet filter simultaneously, the point is servlet should work only with /gameservlet URL, all others should be processed by Struts. I cannot understand how to create URL patterns for my case.
You should add excludePattern constant to struts.xml to exclude servlet mapping URL from Struts processing.
<struts>
<constant name="struts.action.excludePattern" value="/gameservlet/?.*"/>
...
</struts>
来源：https://stackoverflow.com/questions/29084423/how-to-configure-url-patterns-to-have-servlet-and-struts2-to-work-simultaneously