在struts2 的action里,想用request ,怎么办?
在struts2里，我想把一些值存如request   ,以便在页面上获取,,但struts2里面的   action里没有   request   这样的参数,我用HttpServletRequest   request   =   ServletActionContext.getRequest();     却报空指针,我该怎么获取request呢?

struts.xml:
<?xml   version= "1.0 "   encoding= "UTF-8 "?>  
<!DOCTYPE   struts   PUBLIC  
"-//Apache   Software   Foundation//DTD   Struts   Configuration   2.0//EN "  
"http://struts.apache.org/dtds/struts-2.0.dtd ">  
<struts>  
<constant   name= "struts.devMode "   value= "false "   />  
<constant   name= "struts.i18n.encoding "   value= "UTF-8 "   />  
<constant   name= "struts.action.extension "   value= "html "   />  
<constant   name= "struts.objectFactory "   value= "spring "   />  
<constant   name= "struts.custom.i18n.resources "  
value= "ApplicationResources,errors "   />  
<constant   name= "struts.multipart.maxSize "   value= "2097152 "   />  
<constant   name= "struts.ui.theme "   value= "css_xhtml "   />  
<constant   name= "struts.codebehind.pathPrefix "  
value= "/WEB-INF/pages/ "   />

<!--   Include   Struts   defaults   -->  
<include   file= "struts-default.xml "   />

<!--   Configuration   for   the   default   package.   -->  
<package   name= "default "   extends= "struts-default ">  
<default-interceptor-ref   name= "defaultStack "   />  
<!--   DashBoard-->  
<action   name= "dashBoard "   method= "showDashBoard "  
class= "com.flips.action.DashBoard ">  
<result   name= "success "> dashBoard.jsp </result>  
<interceptor-ref   name= "basicStack "/>  
</action>  
</package>  
</struts>


------解决方案--------------------
在ACTION里面引入
HttpServletRequest request = ServletActionContext.getRequest();