struts2使用了拦截器传参数问题,实例主要功能就是文件下载，我不使用拦截器时我可以得到参数的文件名，但使用了就得不到文件的名字。那一位高手帮我看一下，谢谢了
AuthorizationInterceptor.java
package com.tfc.action;

import java.util.Map;
import com.opensymphony.xwork2.Action;
import com.opensymphony.xwork2.ActionInvocation;
import com.opensymphony.xwork2.interceptor.AbstractInterceptor;

@SuppressWarnings("serial")
public class AuthorizationInterceptor extends AbstractInterceptor {

    @SuppressWarnings("unchecked")
    public String intercept(ActionInvocation ai) throws Exception {
        Map session = ai.getInvocationContext().getSession();        
        String role = (String) session.get("username");
        System.out.println("AuthorizationInterceptor.username:\t" + role);
        if (null != role) {
            Object o = ai.getAction();
            System.out.println("AuthorizationInterceptor:o\t" + o);
            if (o instanceof RoleAware) {
                RoleAware action = (RoleAware) o;
                action.setRole(role);
            }
            return ai.invoke();
        } else {
            return Action.LOGIN;
        }
    }

}
LoginAction.java
package com.tfc.action;

import java.util.List;

import javax.servlet.http.HttpServletRequest;

import org.apache.struts2.interceptor.ServletRequestAware;

import com.opensymphony.xwork2.ActionContext;
import com.opensymphony.xwork2.ActionSupport;
import com.tfc.dao.DBUtil;

@SuppressWarnings("serial")
public class LoginAction extends ActionSupport implements ServletRequestAware {
    private String username;
    private String password;
    private HttpServletRequest request;
    @SuppressWarnings("unchecked")
    public String execute() throws Exception {
        // TODO Auto-generated method stub
        DBUtil dbUtil = new DBUtil();
        List userinfolist = dbUtil
                .selectPepoleOne("select * from tfcuserinfo where username='"
                        + username + "'and password='" + password + "'");
        System.out.print(userinfolist.size());
        @SuppressWarnings("unused")
        // loginInfo 0 未登陆，1登陆成功，2登陆失败
        int loginInfo = 0;
        if (userinfolist.size() > 0) {
            loginInfo = 1;
            request.setAttribute("userinfoList", userinfolist);
            ActionContext.getContext().getSession().put("userinfolist", userinfolist);
            request.setAttribute("loginInfo", loginInfo);
            ActionContext.getContext().getSession().put("username", username);
            return ActionSupport.SUCCESS;
        } else {
            loginInfo = 2;
            request.setAttribute("loginInfo", loginInfo);
            return ActionSupport.INPUT;
        }
    }

    public void setServletRequest(HttpServletRequest request) {
        // TODO Auto-generated method stub
        this.request = request;
    }

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }
}
DownloadAction.java
package com.tfc.action;

import java.io.InputStream;

import javax.servlet.http.HttpServletRequest;

import org.apache.struts2.ServletActionContext;
import org.apache.struts2.interceptor.ServletRequestAware;

import com.opensymphony.xwork2.ActionContext;
import com.opensymphony.xwork2.ActionSupport;

@SuppressWarnings("serial")
public class DownloadAction extends ActionSupport implements
        ServletRequestAware, RoleAware {
    private String filename;
    private String role;
    private HttpServletRequest request;

    public InputStream getDownloadFile() {
        System.out.println("DownloadFile2");
        return ServletActionContext.getServletContext().getResourceAsStream(
                "/images/" + "11.rar");
    }

    public String execute() {
        System.out.println("execute1");
        System.out.println("/images/" + filename);
        System.out.println("/role/" + role);
        String username = (String) ActionContext.getContext().getSession().get(
                "username");
        System.out.println("username:\t"+username);
        return SUCCESS;
    }

    public String getFilename() {
        return filename;
    }

    public void setFilename(String filename) {
        this.filename = request.getParameter("filename");
    }

    public void setRole(String role) {
        this.role = role;
    }

    public String getRole() {
        return role;
    }

    public void setServletRequest(HttpServletRequest request) {
        // TODO Auto-generated method stub
        this.request = request;
    }
}
RoleAware.java
package com.tfc.action;

public interface RoleAware {
    void setRole(String role);
}
配置文件,struts.xml
<struts>
    <!-- 解决字符编码 -->
    <constant name="struts.i18n.encoding" value="GB2312" />    
    <package name="default" extends="struts-default">
        <!-- 使用拦截器判断用户是否登陆，如果登陆则下载相应的附件     -->
        <interceptors>
            <interceptor name="auth"
                class="com.tfc.action.AuthorizationInterceptor" />                
        </interceptors>        
        <action name="login" class="com.tfc.action.LoginAction">
            <result type="chain">download</result>
            <result name="success">/download.jsp</result>
            <result name="input">/register.jsp</result>
            <result name="error">/error.jsp</result>
        </action>
        <!-- 不使用栏拦截器下载
            <action name="download" class="com.tfc.action.DownloadAction">
            <result name="success" type="stream">
            <param name="contentType">application/rar</param>
            <param name="contentDisposition">
            filename=${filename}
            </param>
            <param name="inputName">downloadFile</param>
            </result>
            <result name="login">/login.jsp</result>
            <result name="input">/login.jsp</result>
            <result name="error">/error.jsp</result>
            </action>-->
        <!--使用拦截器下载 -->
        <action name="download" class="com.tfc.action.DownloadAction">
            <interceptor-ref name="auth" />
            <result name="success" type="stream">
                <param name="contentType">application/rar</param>
                <param name="contentDisposition">
                    filename=${filename}
                </param>
                <param name="inputName">downloadFile</param>
            </result>
            <result name="login">/login.jsp</result>
            <result name="error">/error.jsp</result>
        </action>       
    </package>
    <include file="struts-default.xml"> </include> 
</struts>
页面测试：download.jsp
<%@ page language="java" pageEncoding="GB2312"%>
<%@ taglib uri="/struts-tags" prefix="s"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
    <head>
        <title>四川省土壤肥料与生态建设信息网资源下载</title>
        <!--
    <link rel="stylesheet" type="text/css" href="styles.css">
    -->

    </head>
    <%
        int loginInfo = (Integer) request.getAttribute("loginInfo");
        if (loginInfo == 1) {
    %>
    <script type="text/javascript">
              alert("登陆成功");
          </script>
    <%
        }
    %>
    <body>
        <%--头部--%>
        <table>
            <tr>
                <td></td>
            </tr>
        </table>
        <table>
            <tr>
                <td>
                    ${sessionScope.username }您好！
                    <a href="u    serinfo.jsp">个人信息</a>
                </td>
            </tr>
        </table>
        <input type="hidden" name="fName" value="11.rar" />
        <s:a href="download.action?filename=11.rar">11.rar</s:a>
        <%--尾部--%>
        <table>
            <tr>
                <td>
                    
                </td>
            </tr>
        </table>
    </body>
</html>
login.jsp
<%@ page language="java"  pageEncoding="GB2312"%>
<%@ taglib uri="/struts-tags" prefix="s" %>
    <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
    <html>
        <head>
        <title>四川省土壤肥料与生态建设信息网用户登陆</title>
        <script type="text/javascript">
            function validate(){
                var usernameValue = document.getElementById("username").value;
                var passwordValue = document.getElementById("password").value;
                if(null == usernameValue || usernameValue.length <= 0){
                    alert("用户帐号不能为空");
                    return false;
                }    
                else if(null == passwordValue || passwordValue.length <=0){
                    alert("用户密码不能为空");
                    return false;
                }
                return true;
            }
        </script>          
        </head>
        <body>
            <%--头部--%>
            <table>
                <tr>
                    <td></td>
                </tr>
            </table>
            <%--用户信息列表--%>
            <table>
                <tr>
                <td>会员登陆</td><td>${requestScope.registerInfo}</td>
                </tr>
            </table>
            <form action="login.action" method="post" onsubmit="return validate();">
                <table border="0">
                    <tr>
                        <td>
                            用户帐号:
                        </td>
                        <td>
                            <input type="text" name="username" id="username" />
                        </td>                        
                    </tr>
                    <tr>
                        <td>
                            用户密码:
                        </td>
                        <td>
                            <input type="password" name="password" id="password" />
                        </td>                        
                    </tr>
                    <tr>
                        <td><input type="submit" name="su" value="登陆" /></td>
                        <td><a href="javascript:window.open('backPassword.jsp')">忘记密码</a></td>
                    </tr>
                </table>
                <a href="register.jsp" target="_blank">用户注册</a>
                </form>
                    <%--尾部--%>
                    <table>
                        <tr>
                            <td></td>
                        </tr>
                    </table>
        </body>
    </html>

访问的地址:http:/127.0.0.1:8080/download.action
若用户没有进行登陆的时候直接访问下截地址，将跳到用户登陆对话框。现在的问题主要是在downloadaction里得不到文件的名称，那一位知道了原因请告诉我，谢谢了。我都解决好几天了.急哈！！