SpringMVC文件上传和下载

上传与下载

1文件上传

1.1加入jar包

文件上传需要依赖的jar包

1.2配置部件解析器

解析二进制流数据。

<?xml version="1.0" encoding="UTF-8"?>
<!-- 到入xml文件的约束 -->

<beans xmlns="http://www.springframework.org/schema/beans"
 xmlns:context="http://www.springframework.org/schema/context"
 xmlns:mvc="http://www.springframework.org/schema/mvc"
 xmlns:p="http://www.springframework.org/schema/p"
 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 xsi:schemaLocation="http://www.springframework.org/schema/beans 10  http://www.springframework.org/schema/beans/spring-beans-4.1.xsd 11  http://www.springframework.org/schema/context 12  http://www.springframework.org/schema/context/spring-context-4.1.xsd 13  http://www.springframework.org/schema/mvc 14  http://www.springframework.org/schema/mvc/spring-mvc-4.1.xsd 15  ">
      
      <!-- 开启注解扫描（将对象纳入spring容器） -->
      <context:component-scan base-package="org.guangsoft.controller">
      </context:component-scan> 
      
     <!-- 开始springmvc的映射注解和适配注解 -->
     <mvc:annotation-driven></mvc:annotation-driven>
     
     
     <!-- 实例化文件上传的解析器（MIME） -->
     <bean id="multipartResolver" 
 class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
         <property name="defaultEncoding" value="utf-8"></property><!-- 客户端发送数据的编码 -->
         <property name="maxUploadSize" value="5242880"></property><!-- 上传文件的大小 -->
         <property name="uploadTempDir" value="/upload"></property>
     </bean>
     
</beans> 

1.3建立FileController

package org.guangsoft.controller;  2 import java.io.File;  3 import java.io.IOException;  4 import java.util.UUID;  5 import javax.servlet.http.HttpSession;  6 import org.apache.commons.io.FileUtils;  7 import org.springframework.http.HttpHeaders;  8 import org.springframework.http.HttpStatus;  9 import org.springframework.http.MediaType; 10 import org.springframework.http.ResponseEntity; 11 import org.springframework.stereotype.Controller; 12 import org.springframework.web.bind.annotation.RequestMapping; 13 import org.springframework.web.bind.annotation.RequestParam; 14 import org.springframework.web.multipart.commons.CommonsMultipartFile; 15 @Controller 16 public class FileController 17 { 18     /*** 19  * 实现文件的上传 20  * 21  * @RequestParam:指定客户端发送数据的名字 22  * **/
    @RequestMapping("/uploadFile") 24     public String uploadFile(@RequestParam("cmf") CommonsMultipartFile cmf, 25  HttpSession session) 26  { 27         // 1获得上传的文件内容
        byte[] bytes = cmf.getBytes(); 29         // 2获得upload的绝对路径
        String path = session.getServletContext().getRealPath("/upload"); 31         // 3在服务器的upload目录下创建File对象
        String oname = cmf.getOriginalFilename(); // 上传文件的原始名字
        String uuid = UUID.randomUUID().toString(); 34         File file = new File(path, uuid 35                 + oname.substring(oname.lastIndexOf("."))); 36         // 4将上传的文件拷贝到指定的目录
        try
 { 39  FileUtils.writeByteArrayToFile(file, bytes); 40  } 41         catch (IOException e) 42  { 43  e.printStackTrace(); 44  } 45         return "index.jsp"; 46  } 47     /*** 48  * 实现文件下载 49  * ***/
    @RequestMapping("/download") 51     public ResponseEntity download(HttpSession session) 52  { 53         // 用来封装响应头信息
        HttpHeaders responseHeaders = new HttpHeaders(); 55         // 下载的附件的类型
 responseHeaders.setContentType(MediaType.APPLICATION_OCTET_STREAM); 57         // 下载的附件的名称
        responseHeaders.setContentDispositionFormData("attachment", "1.png"); 59         String path = session.getServletContext().getRealPath("/upload"); 60         String fname = "b8abd107-ecdd-49ae-9175-b39f1d18a288.png"; // 数据库查询获得 61         // 将下载的文件封装流对象
        File file = new File(path, fname); 63         try
 { 65             /**
 * arg1:需要响应到客户端的数据 arg2:设置本次请求的响应头 arg3:响应到客户端的状态码 67  * ***/
            return new ResponseEntity(FileUtils.readFileToByteArray(file), 69  responseHeaders, HttpStatus.CREATED); 70  } 71         catch (IOException e) 72  { 73  e.printStackTrace(); 74  } 75         return null; 76  } 77 } 

1.4建立视图页面

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();  4 String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";  5 %>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
  <head>
    <base href="<%=basePath%>">
    <title>upload</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">
  </head>
  
  <body>
    <form action="uploadFile.action" method="post" 
 enctype="multipart/form-data">
        <div>file<input name="cmf" type="file"/></div>
        <div> <input type="submit" value="提交"/></div>
    </form>
    <hr/>
    <a href="download.action">下载</a>
  </body>
</html> 

2 文件下载

2.1建立下的handler方法

见上