用struts做的基于web的小程序页面显示空白!
代码如下:
web.xml

<?xml   version= "1.0 "   encoding= "UTF-8 "?>
<!DOCTYPE   web-app   PUBLIC   "-//Sun   Microsystems,   Inc.//DTD   Web   Application   2.3//EN "   "http://java.sun.com/dtd/web-app_2_3.dtd ">
<web-app>

<display-name> test </display-name>
<listener>
<listener-class> com.common.TimerListener </listener-class>
</listener>

<filter>
<filter-name> EncodingFilter </filter-name>
<display-name> EncodingFilter </display-name>
<filter-class> com.common.EncodingFilter </filter-class>
<init-param>
<param-name> encoding </param-name>
<param-value> UTF-8 </param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name> EncodingFilter </filter-name>
<url-pattern> /* </url-pattern>
</filter-mapping>


<servlet>
<servlet-name> action </servlet-name>
<servlet-class> org.apache.struts.action.ActionServlet </servlet-class>
<init-param>
<param-name> debug </param-name>
<param-value> 2 </param-value>
</init-param>
<init-param>
<param-name> config </param-name>
<param-value> /WEB-INF/struts-config.xml </param-value>
</init-param>
<load-on-startup> 2 </load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name> action </servlet-name>
<url-pattern> *.do </url-pattern>
</servlet-mapping>

<session-config>
<session-timeout> 60 </session-timeout>
</session-config>

<welcome-file-list>
<welcome-file> /jsp/main.jsp </welcome-file>
</welcome-file-list>

<taglib>
<taglib-uri> /tags/struts-bean </taglib-uri>
<taglib-location> /WEB-INF/tld/struts-bean.tld </taglib-location>
</taglib>
<taglib>
<taglib-uri> /tags/struts-html </taglib-uri>
<taglib-location> /WEB-INF/tld/struts-html.tld </taglib-location>
</taglib>
<taglib>
<taglib-uri> /tags/struts-logic </taglib-uri>
<taglib-location> /WEB-INF/tld/struts-logic.tld </taglib-location>
</taglib>
<taglib>
<taglib-uri> /tags/struts-nested </taglib-uri>
<taglib-location> /WEB-INF/tld/struts-nested.tld </taglib-location>
</taglib>
<taglib>
<taglib-uri> /tags/struts-tiles </taglib-uri>
<taglib-location> /WEB-INF/tld/struts-tiles.tld </taglib-location>
</taglib>
</web-app>

struts-config.xml配置如下:
<?xml   version= "1.0 "   encoding= "UTF-8 "?>
<!DOCTYPE   struts-config   PUBLIC   "-//Apache   Software   Foundation//DTD   Struts   Configuration   1.1//EN "   "http://jakarta.apache.org/struts/dtds/struts-config_1_2.dtd ">
<struts-config>
<form-beans>
<form-bean   name= "fileUploadForm "   typ