strus2 自定义 intercept 时 对象为null 解救方案

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE struts PUBLIC
    "-//Apache Software Foundation//DTD Struts Configuration 2.1.7//EN"
    "http://struts.apache.org/dtds/struts-2.1.7.dtd">
<struts>

<include file="conf/struts/struts_demo.xml"></include>
<package name="zskx-demo-mytest" abstract="ture" extends="struts-default,json-default">


<interceptors>
<interceptor name="permissioninterceptor" class="com.zskx.demo.application.filter.permissionIntercepter"/>
<interceptor-stack name="permissionDefaultStack">
<interceptor-ref name="fileUpload">
                 <param name="maximumSize">204800000</param>
                </interceptor-ref>
                <interceptor-ref name="defaultStack"/>
                <interceptor-ref name="permissioninterceptor"></interceptor-ref>
</interceptor-stack>
</interceptors>
      <default-interceptor-ref name="permissionDefaultStack" />

<!-- 全局转向 -->

   <global-results>
       <result name="input">/WEB-INF/pages/hello.jsp</result>
       <result name="login">/WEB-INF/pages/login.vm</result>
   </global-results>
<!-- 全局转向 -->
  

</package>

<constant name="struts.velocity.toolboxlocation" value="WEB-INF/toolbox.xml" />
</struts>