实现文件下载的FileDownloadAction:提供一个返回InputStream流的方法。
DownAction.java
package action;
import java.io.InputStream;
import org.apache.struts2.ServletActionContext;
import com.opensymphony.xwork2.ActionSupport;
public class DownAction extends ActionSupport{
/**
* 定义一个返回InputStream的方法，
该方法将作为被下载文件的入口，
且需要配置stream类型结果时指定inputName参数，
inputName参数的值就是方法去掉get前缀、首字母小写的字符串
*/
private static final long serialVersionUID = 1L;
private String inputPath;//该属性可以在配置文件中动态指定该属性值
public InputStream getTargetFile() throws Exception {
return ServletActionContext.getServletContext().getResourceAsStream(inputPath);//ServletContext提供getResourceAsStream()方法
//返回指定文件对应的输入流
}
public void setInputPath(String value) {//依赖注入该属性值的setter方法
inputPath = value;
}
}
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<base href="<%=basePath%>">
<title>My JSP ‘down.jsp‘ starting page</title>
<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="This is my page">
<!--
<link rel="stylesheet" type="text/css" href="styles.css">
-->
</head>
<body>
<a href="/Upload-1/uploadFiles/xia.png">123</a>
<a href="/Upload-1/uploadFiles/中文.png">中文</a>
</body>
</html>
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE struts PUBLIC
"-//Apache Software Foundation//DTD Struts Configuration 2.3//EN"
"http://struts.apache.org/dtds/struts-2.3.dtd">
<struts>
<package name="hello" namespace="/hello" extends="struts-default">
<action name="down" class="action.DownAction">
<param name="inputPath">\uploadFiles\xia.png</param>
<result name="success" type="stream">
<param name="contentType">image/x-png</param>
<param name="inputName">targetFile</param>
<param name="bufferSize">600000</param>
<param name="contentDisposition">filename="小.jpg"</param>
</result>
</action>
</package>
</struts>
原文：http://blog.csdn.net/yantingmei/article/details/20300111