刚才讲解了Spring MVC实现文件上传，接着，我们看看Spring MVC如何实现文件下载。
1 准备下载的文件
2 设计下载页面
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>一点教程网-文件下载</title>
</head>
<body>
<h3>SpringMVC文件下载</h3>
<a href="/down">下载</a>
</body>
</html>
3 编写DownController
package com.yiidian.controller;
import com.yiidian.domain.User;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.ui.ModelMap;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.multipart.MultipartFile;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.io.*;
import java.util.UUID;
/**
* 演示Spring MVC文件下载
* 一点教程网 - www.yiidian.com
*/
@Controller
public class DownController {
/**
* 下载文件
*/
@RequestMapping("/down")
public void upload(HttpSession session, HttpServletResponse response) throws Exception {
//模拟文件下载
//1.读取需要下载的文件
InputStream inputStream = session.getServletContext()
.getResourceAsStream("/upload/spring.jpg");
//2.输出文件
//设置响应头
response.setHeader("Content-Disposition","attachment;filename=spring.jpg");
OutputStream outputStream = response.getOutputStream();
byte[] buf = new byte[1024];
int len = 0;
while( (len = inputStream.read(buf))!=-1 ){
outputStream.write(buf,0,len);
}
//3.关闭资源
outputStream.close();
inputStream.close();
}
}
4 运行测试
