任何MVC框架都需要与Web应用整合，这就不得不借助于web.xml文件，只有配置在web.xml文件中Servlet才会被应用加载。 
通常，所有的MVC框架都需要Web应用加载一个核心控制器，对于Struts2框架而言，需要加载FilterDispatcher，只要Web应用负责加载FilterDispatcher，FilterDispatcher将会加载Struts2框架。 
因为Struts2将核心控制器设计成Filter，而不是一个普通Servlet。故为了让Web应用加载FilterDispatcher，只需要在web.xml文件中配置FilterDispatcher即可。 
标准配置文件如下：

<?xml version="1.0" encoding="UTF-8"?>
<web-app id="WebApp_9" version="2.4" xmlns="http://java.sun.com/xml/ns/j2ee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">  <display-name>Struts Blank</display-name>  <filter>  <!-- 配置Struts2核心Filter的名字 -->  <filter-name>struts2</filter-name>  <!-- 配置Struts2核心Filter的实现类 -->  <filter-class>org.apache.struts2.dispatcher.FilterDispatcher</filter-class>  <init-param>  <!-- 配置Struts2框架默认加载的Action包结构，可以没有。 -->  <param-name>actionPackages</param-name>  <param-value>org.apache.struts2.showcase.person</param-value>  </init-param>  <!-- 配置Struts2框架的配置提供者类 -->  <init-param>  <param-name>configProviders</param-name>  <param-value>lee.MyConfigurationProvider</param-value>  </init-param>  </filter>  <!-- 配置Filter拦截的URL -->  <filter-mapping>  <!-- 配置Struts2的核心FilterDispatcher拦截所有用户请求 -->  <filter-name>struts2</filter-name>  <url-pattern>/*</url-pattern>  </filter-mapping>  <welcome-file-list>  <welcome-file>index.html</welcome-file>  </welcome-file-list>
</web-app>  

全部配置如下

<?xml version="1.0" encoding="UTF-8"?>
<web-app id="WebApp_9" version="2.4" xmlns="http://java.sun.com/xml/ns/j2ee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd"><display-name>Struts Showcase Application</display-name><filter><filter-name>struts-prepare</filter-name><filter-class>org.apache.struts2.dispatcher.filter.StrutsPrepareFilter</filter-class></filter><filter><filter-name>struts-execute</filter-name><filter-class>org.apache.struts2.dispatcher.filter.StrutsExecuteFilter</filter-class></filter><filter><filter-name>sitemesh</filter-name><filter-class>com.opensymphony.sitemesh.webapp.SiteMeshFilter</filter-class></filter><filter-mapping><filter-name>struts-prepare</filter-name><url-pattern>/*</url-pattern></filter-mapping><filter-mapping><filter-name>sitemesh</filter-name><url-pattern>/*</url-pattern></filter-mapping><filter-mapping><filter-name>struts-execute</filter-name><url-pattern>/*</url-pattern></filter-mapping><listener><listener-class>org.springframework.web.context.ContextLoaderListener</listener-class></listener><listener><listener-class>org.apache.struts2.tiles.StrutsTilesListener</listener-class></listener><!-- Chat Example in Showcase --><listener><listener-class>org.apache.struts2.showcase.chat.ChatSessionListener</listener-class></listener><listener><listener-class>org.apache.struts2.dispatcher.listener.StrutsListener</listener-class></listener><!-- SNIPPET START: dwr --><servlet><servlet-name>dwr</servlet-name><servlet-class>uk.ltd.getahead.dwr.DWRServlet</servlet-class><init-param><param-name>debug</param-name><param-value>true</param-value></init-param></servlet><servlet><servlet-name>JspSupportServlet</servlet-name><servlet-class>org.apache.struts2.views.JspSupportServlet</servlet-class><load-on-startup>1</load-on-startup></servlet><!-- Sitemesh Freemarker and Velocity Decorator Servlets. Shares configuration with Struts.--><servlet><servlet-name>sitemesh-freemarker</servlet-name><servlet-class>org.apache.struts2.sitemesh.FreemarkerDecoratorServlet</servlet-class><init-param><param-name>default_encoding</param-name><param-value>UTF-8</param-value></init-param><load-on-startup>1</load-on-startup></servlet><servlet><servlet-name>sitemesh-velocity</servlet-name><servlet-class>org.apache.struts2.sitemesh.VelocityDecoratorServlet</servlet-class><init-param><param-name>default_encoding</param-name><param-value>UTF-8</param-value></init-param><load-on-startup>1</load-on-startup></servlet><servlet-mapping><servlet-name>dwr</servlet-name><url-pattern>/dwr/*</url-pattern></servlet-mapping><servlet-mapping><servlet-name>sitemesh-freemarker</servlet-name><url-pattern>*.ftl</url-pattern></servlet-mapping><servlet-mapping><servlet-name>sitemesh-velocity</servlet-name><url-pattern>*.vm</url-pattern></servlet-mapping><!-- END SNIPPET: dwr --><!-- SNIPPET START: example.velocity.filter.chain<filter><filter-name>struts-cleanup</filter-name><filter-class>org.apache.struts2.dispatcher.ActionContextCleanUp</filter-class></filter><filter><filter-name>sitemesh</filter-name><filter-class>org.apache.struts2.sitemesh.VelocityPageFilter</filter-class></filter><filter><filter-name>struts</filter-name><filter-class>org.apache.struts2.dispatcher.FilterDispatcher</filter-class></filter><filter-mapping><filter-name>struts-cleanup</filter-name><url-pattern>/*</url-pattern></filter-mapping><filter-mapping><filter-name>sitemesh</filter-name><url-pattern>/*</url-pattern></filter-mapping><filter-mapping><filter-name>struts</filter-name><url-pattern>/*</url-pattern></filter-mapping>END SNIPPET: example.velocity.filter.chain --><!-- SNIPPET START: example.freemarker.filter.chain<filter><filter-name>struts-cleanup</filter-name><filter-class>org.apache.struts2.dispatcher.ActionContextCleanUp</filter-class></filter><filter><filter-name>sitemesh</filter-name><filter-class>org.apache.struts2.sitemesh.FreeMarkerPageFilter</filter-class></filter><filter><filter-name>struts</filter-name><filter-class>org.apache.struts2.dispatcher.FilterDispatcher</filter-class></filter><filter-mapping><filter-name>struts-cleanup</filter-name><url-pattern>/*</url-pattern></filter-mapping><filter-mapping><filter-name>sitemesh</filter-name><url-pattern>/*</url-pattern></filter-mapping><filter-mapping><filter-name>struts</filter-name><url-pattern>/*</url-pattern></filter-mapping>END SNIPPET: example.freemarker.filter.chain --><welcome-file-list><welcome-file>index.jsp</welcome-file><welcome-file>default.jsp</welcome-file><welcome-file>index.html</welcome-file></welcome-file-list><!-- Restricts access to pure JSP files - access available only via Struts action --><security-constraint><display-name>No direct JSP access</display-name><web-resource-collection><web-resource-name>No-JSP</web-resource-name><url-pattern>*.jsp</url-pattern></web-resource-collection><auth-constraint><role-name>no-users</role-name></auth-constraint></security-constraint><security-role><description>Don't assign users to this role</description><role-name>no-users</role-name></security-role></web-app>

*如上，当配置Struts2的FilterDispatcher类时，可以指定一系列的初始化参数，为该Filter配置初始化参数时，其中有3个初始化参数有特殊意义： 
config：使用逗号隔开的字符串，每个字符串都是一个XML配置文件的位置。Struts框架将自动加载该属性指定的系列配置文件。
actionPackages：使用逗号隔开的字符串，每个字符串都是一个包空间，Struts2框架将扫描这些包空间下的Action。 
configProviders：配置自己的ConfigurationProvider类。 
还可以在此处配置Struts2常量，每个<init-param>元素配置一个Struts2常量，其中<param-name>子元素指定了常量name，而<param-value>子元素指定了常量value。

*在web.xml中配置了<Filter>元素，还需要配置该Filter拦截的URL。通常，我们让该Filter拦截所有的用户请求。可以能过<filter-mapping>元素配置。