在Spring MVC的基础框架搭建起来后，我们测试了spring mvc中的返回值类型，如果你还没有搭建好springmvc的架构请参考博文->http://www.cnblogs.com/qixiaoyizhan/p/5819392.html
今天我们来讲讲spring mvc中的文件上传和下载的几种方法。
首先附上文件目录->我们需要配置的我做了记号->
一、文件上传
首先为了方便后续的操作，以及精简代码，我们在Utils包下封装一个文件上传下载的帮助类：Files_Helper_DG
Files_Helper_DG 代码
package Utils; 2 3 import org.springframework.web.multipart.MultipartFile; 4 5 import javax.servlet.http.HttpServletRequest; 6 import javax.servlet.http.HttpServletResponse; 7 import java.io.*; 8 import java.text.SimpleDateFormat; 9 import java.util.Date; 10 import java.util.UUID; 11 12 /** 13 * Author:qixiao 14 * Time:2016-9-2 23:47:51 15 */ 16 public final class Files_Utils_DG { 17 /** 18 * private constructor method that make class can not be instantiation 19 */ 20 private Files_Utils_DG() { 21 throw new Error("The class Cannot be instance !"); 22 } 23 24 /** 25 * spring mvc files Upload method (transferTo method) 26 * MultipartFile use TransferTo method upload 27 * 28 * @param request HttpServletRequest 29 * @param multipartFile MultipartFile(spring) 30 * @param filePath filePath example "/files/Upload" 31 * @return 32 */ 33 public static String FilesUpload_transferTo_spring(HttpServletRequest request, MultipartFile multipartFile, String filePath) { 34 if (multipartFile != null) { 35 //get files suffix 36 String suffix = multipartFile.getOriginalFilename().substring(multipartFile.getOriginalFilename().lastIndexOf(".")); 37 //filePath+fileName the complex file Name 38 String absolutePath = getAndSetAbsolutePath(request, filePath, suffix); 39 //return relative Path 40 String relativePath = getRelativePath(filePath, suffix); 41 try { 42 //save file 43 multipartFile.transferTo(new File(absolutePath)); 44 //return relative Path 45 return relativePath; 46 } catch (IOException e) { 47 e.printStackTrace(); 48 return null; 49 } 50 } else 51 return null; 52 } 53 54 /** 55 * user stream type save files 56 * @param request HttpServletRequest 57 * @param multipartFile MultipartFile support CommonsMultipartFile file 58 * @param filePath filePath example "/files/Upload" 59 * @return 60 */ 61 public static String FilesUpload_stream(HttpServletRequest request,MultipartFile multipartFile,String filePath) { 62 if (multipartFile != null) { 63 //get files suffix 64 String suffix = multipartFile.getOriginalFilename().substring(multipartFile.getOriginalFilename().lastIndexOf(".")); 65 //filePath+fileName the complex file Name 66 String absolutePath = getAndSetAbsolutePath(request, filePath, suffix); 67 //return relative Path 68 String relativePath = getRelativePath(filePath, suffix); 69 try{ 70 InputStream inputStream = multipartFile.getInputStream(); 71 FileOutputStream fileOutputStream = new FileOutputStream(absolutePath); 72 byte buffer[] = new byte[4096]; //create a buffer 73 long fileSize = multipartFile.getSize(); 74 if(fileSize<=buffer.length){//if fileSize < buffer 75 buffer = new byte[(int)fileSize]; 76 } 77 int line =0; 78 while((line = inputStream.read(buffer)) >0 ) 79 { 80 fileOutputStream.write(buffer,0,line); 81 } 82 fileOutputStream.close(); 83 inputStream.close(); 84 return relativePath; 85 }catch (Exception e){ 86 e.printStackTrace(); 87 } 88 } else 89 return null; 90 return null; 91 } 92 93 /** 94 * @param request HttpServletRequest 95 * @param response HttpServletResponse 96 * @param filePath example "/filesOut/Download/mst.txt" 97 * @return 98 */ 99 public static void FilesDownload_stream(HttpServletRequest request, HttpServletResponse response, String filePath) { 100 //get server path (real path) 101 String realPath = request.getSession().getServletContext().getRealPath(filePath); 102 File file = new File(realPath); 103 String filenames = file.getName(); 104 InputStream inputStream; 105 try { 106 inputStream = new BufferedInputStream(new FileInputStream(file)); 107 byte[] buffer = new byte[inputStream.available()]; 108 inputStream.read(buffer); 109 inputStream.close(); 110 response.reset(); 111 // 先去掉文件名称中的空格,然后转换编码格式为utf-8,保证不出现乱码,这个文件名称用于浏览器的下载框中自动显示的文件名 112 response.addHeader("Content-Disposition", "attachment;filename=" + new String(filenames.replaceAll(" ", "").getBytes("utf-8"), "iso8859-1")); 113 response.addHeader("Content-Length", "" + file.length()); 114 OutputStream os = new BufferedOutputStream(response.getOutputStream()); 115 response.setContentType("application/octet-stream"); 116 os.write(buffer);// 输出文件 117 os.flush(); 118 os.close(); 119 } catch (Exception e) { 120 e.printStackTrace(); 121 } 122 } 123 124 125 //------------------------------------------------------------------------------- 126 //return server absolute path（real path） 127 public static String getServerPath(HttpServletRequest request, String filePath) { 128 return request.getSession().getServletContext().getRealPath(filePath); 129 } 130 131 //return a dir that named date of today ; example:20160912 132 public static String getDataPath() { 133 return new SimpleDateFormat("yyyyMMdd").format(new Date()); 134 } 135 136 //check if the path has exist if not create it 137 public static void checkDir(String savePath) { 138 File dir = new File(savePath); 139 if (!dir.exists() || !dir.isDirectory()) { 140 dir.mkdir(); 141 } 142 } 143 144 //return an UUID Name parameter (suffix cover '.') example： ".jpg"、".txt" 145 public static String getUUIDName(String suffix) { 146 return UUID.randomUUID().toString() + suffix;// make new file name 147 } 148 149 //return server absolute path（real path） the style is “server absolute path/DataPath/UUIDName”filePath example "/files/Upload" 150 public static String getAndSetAbsolutePath(HttpServletRequest request, String filePath, String suffix) { 151 String savePath = getServerPath(request, filePath) + File.separator + getDataPath() + File.separator;//example:F:/qixiao/files/Upload/20160912/ 152 checkDir(savePath);//check if the path has exist if not create it 153 return savePath + getUUIDName(suffix); 154 } 155 156 //get the relative path of files style is “/filePath/DataPath/UUIDName”filePath example "/files/Upload" 157 public static String getRelativePath(String filePath, String suffix) { 158 return filePath + File.separator + getDataPath() + File.separator + getUUIDName(suffix);//example:/files/Upload/20160912/ 159 } 160 }
然后我们新建一个控制器类 FileUploadController
首先我们先展示出全部的代码，然后我们进行分步说明--->
1 package HelloSpringMVC.controller; 2 3 4 import Utils.Files_Utils_DG; 5 import org.springframework.stereotype.Controller; 6 import org.springframework.web.bind.annotation.RequestMapping; 7 import org.springframework.web.bind.annotation.RequestMethod; 8 import org.springframework.web.bind.annotation.RequestParam; 9 import org.springframework.web.bind.annotation.ResponseBody; 10 import org.springframework.web.multipart.MultipartFile; 11 import org.springframework.web.multipart.MultipartHttpServletRequest; 12 import org.springframework.web.multipart.commons.CommonsMultipartResolver; 13 14 import javax.servlet.http.HttpServletRequest; 15 import javax.servlet.http.HttpServletResponse; 16 import java.util.Iterator; 17 18 /** 19 * Created by qixiao on 2016/8/30. 20 */ 21 @Controller 22 @RequestMapping(value = "/FileUpload/*") 23 public class FileUploadController { 24 25 /* 26 * 方式一 27 * 采用 fileUpload_multipartFile ， file.transferTo 来保存上传的文件 28 */ 29 @RequestMapping(value = "fileUpload_multipartFile") 30 @ResponseBody 31 public String fileUpload_multipartFile(HttpServletRequest request, @RequestParam("file_upload") MultipartFile multipartFile) { 32 //调用保存文件的帮助类进行保存文件，并返回文件的相对路径 33 String filePath = Files_Utils_DG.FilesUpload_transferTo_spring(request, multipartFile, "/files/upload"); 34 return "{'TFMark':'true','Msg':'upload success !','filePath':'" + filePath + "'}"; 35 } 36 37 /* 38 * 方式二 39 * 采用 fileUpload_multipartRequest file.transferTo 来保存上传文件 40 * 参数不写 MultipartFile multipartFile 在request请求里面直接转成multipartRequest，从multipartRequest中获取到文件流 41 */ 42 @RequestMapping(value = "fileUpload_multipartRequest") 43 @ResponseBody 44 public String fileUpload_multipartRequest(HttpServletRequest request) { 45 //将request转成MultipartHttpServletRequest 46 MultipartHttpServletRequest multipartRequest = (MultipartHttpServletRequest) request; 47 //页面控件的文件流，对应页面控件 input file_upload 48 MultipartFile multipartFile = multipartRequest.getFile("file_upload"); 49 //调用保存文件的帮助类进行保存文件，并返回文件的相对路径 50 String filePath = Files_Utils_DG.FilesUpload_transferTo_spring(request, multipartFile, "/files/upload"); 51 return "{'TFMark':'true','Msg':'upload success !','filePath':'" + filePath + "'}"; 52 } 53 54 /* 55 * 方式三 56 * 采用 CommonsMultipartResolver file.transferTo 来保存上传文件 57 * 自动扫描全部的input表单 58 */ 59 @RequestMapping(value = "fileUpload_CommonsMultipartResolver") 60 @ResponseBody 61 public String fileUpload_CommonsMultipartResolver(HttpServletRequest request) { 62 //将当前上下文初始化给 CommonsMultipartResolver （多部分解析器） 63 CommonsMultipartResolver multipartResolver = new CommonsMultipartResolver(request.getSession().getServletContext()); 64 //检查form中是否有enctype="multipart/form-data" 65 if (multipartResolver.isMultipart(request)) { 66 //将request变成多部分request 67 MultipartHttpServletRequest multipartRequest = (MultipartHttpServletRequest) request; 68 //获取multiRequest 中所有的文件名 69 Iterator iter = multipartRequest.getFileNames(); 70 while (iter.hasNext()) { 71 //一次遍历所有文件 72 MultipartFile multipartFile = multipartRequest.getFile(iter.next().toString()); 73 //调用保存文件的帮助类进行保存文件，并返回文件的相对路径 74 String fileName = Files_Utils_DG.FilesUpload_transferTo_spring(request, multipartFile, "/files/upload"); 75 System.out.println(fileName); 76 } 77 } 78 return "upload success ! "; 79 } 80 81 /* 82 * 方式四 83 * 通过流的方式上传文件 84 */ 85 @RequestMapping("fileUpload_stream") 86 @ResponseBody 87 public String upFile(HttpServletRequest request, @RequestParam("file_upload") MultipartFile multipartFile){ 88 String filePath= Files_Utils_DG.FilesUpload_stream(request,multipartFile,"/files/upload"); 89 return "{'TFMark':'true','Msg':'upload success !','filePath':'" + filePath + "'}"; 90 } 91 92 /* 93 * 方式五 94 * 采用 fileUpload_ajax ， file.transferTo 来保存上传的文件 异步 95 */ 96 @RequestMapping(value = "fileUpload_ajax",method = RequestMethod.POST,produces = {"application/json;charset=UTF-8"}) 97 @ResponseBody 98 public String fileUpload_ajax(HttpServletRequest request, @RequestParam("file_AjaxFile") MultipartFile multipartFile) { 99 //调用保存文件的帮助类进行保存文件，并返回文件的相对路径 100 String filePath = Files_Utils_DG.FilesUpload_transferTo_spring(request, multipartFile, "/files/upload"); 101 return "{'TFMark':'true','Msg':'upload success !','filePath':'" + filePath + "'}"; 102 } 103 104 /* 105 * 多文件上传 106 * 采用 MultipartFile[] multipartFile 上传文件方法 107 */ 108 @RequestMapping(value = "fileUpload_spring_list") 109 @ResponseBody 110 public String fileUpload_spring_list(HttpServletRequest request, @RequestParam("file_upload") MultipartFile[] multipartFile) { 111 //判断file数组不能为空并且长度大于0 112 if (multipartFile != null && multipartFile.length > 0) { 113 //循环获取file数组中得文件 114 try { 115 for (int i = 0; i < multipartFile.length; i++) { 116 MultipartFile file = multipartFile[i]; 117 //保存文件 118 String fileName = Files_Utils_DG.FilesUpload_transferTo_spring(request, file, "/files/upload"); 119 System.out.println(fileName); 120 } 121 return "{'TFMark':'true','Msg':'upload success !'}"; 122 } catch (Exception ee) { 123 return "{'TFMark':'false','Msg':'参数传递有误！'}"; 124 } 125 } 126 return "{'TFMark':'false','Msg':'参数传递有误！'}"; 127 } 128 129 /** 130 * 文件下载 131 * 132 * @param response 133 */ 134 @RequestMapping(value = "fileDownload_servlet") 135 public void fileDownload_servlet(HttpServletRequest request, HttpServletResponse response) { 136 Files_Utils_DG.FilesDownload_stream(request,response,"/files/download/mst.txt"); 137 } 138 } 复制代码 方式一：采用 fileUpload_multipartFile ， file.transferTo 来保存上传的文件 复制代码 1 /* 2 * 方式一 3 * 采用 fileUpload_multipartFile ， file.transferTo 来保存上传的文件 4 */ 5 @RequestMapping(value = "fileUpload_multipartFile") 6 @ResponseBody 7 public String fileUpload_multipartFile(HttpServletRequest request, @RequestParam("file_upload") MultipartFile multipartFile) { 8 //调用保存文件的帮助类进行保存文件，并返回文件的相对路径 9 String filePath = Files_Helper_DG.FilesUpload_transferTo_spring(request, multipartFile, "/filesOut/Upload"); 10 return "{"TFMark":"true","Msg":"upload success !","filePath":"" + filePath + ""}"; 11 } 复制代码 方式二：采用 fileUpload_multipartRequest file.transferTo 来保存上传文件 复制代码 1 @RequestMapping(value = "fileUpload_multipartRequest") 2 @ResponseBody 3 public String fileUpload_multipartRequest(HttpServletRequest request) { 4 //将request转成MultipartHttpServletRequest 5 MultipartHttpServletRequest multipartRequest = (MultipartHttpServletRequest) request; 6 //页面控件的文件流，对应页面控件 input file_upload 7 MultipartFile multipartFile = multipartRequest.getFile("file_upload"); 8 //调用保存文件的帮助类进行保存文件，并返回文件的相对路径 9 String filePath = Files_Helper_DG.FilesUpload_transferTo_spring(request, multipartFile, "/filesOut/Upload"); 10 return "{"TFMark":"true","Msg":"upload success !","filePath":"" + filePath + ""}"; 11 } 复制代码 方式三：采用 CommonsMultipartResolver file.transferTo 来保存上传文件---自动扫描全部的input表单 复制代码 1 @RequestMapping(value = "fileUpload_CommonsMultipartResolver") 2 @ResponseBody 3 public String fileUpload_CommonsMultipartResolver(HttpServletRequest request) { 4 //将当前上下文初始化给 CommonsMultipartResolver （多部分解析器） 5 CommonsMultipartResolver multipartResolver = new CommonsMultipartResolver(request.getSession().getServletContext()); 6 //检查form中是否有enctype="multipart/form-data" 7 if (multipartResolver.isMultipart(request)) { 8 //将request变成多部分request 9 MultipartHttpServletRequest multipartRequest = (MultipartHttpServletRequest) request; 10 //获取multiRequest 中所有的文件名 11 Iterator iter = multipartRequest.getFileNames(); 12 while (iter.hasNext()) { 13 //一次遍历所有文件 14 MultipartFile multipartFile = multipartRequest.getFile(iter.next().toString()); 15 //调用保存文件的帮助类进行保存文件，并返回文件的相对路径 16 String fileName = Files_Helper_DG.FilesUpload_transferTo_spring(request, multipartFile, "/filesOut/Upload"); 17 System.out.println(fileName); 18 } 19 } 20 return "upload success ! "; 21 }
方式四：通过流的方式上传文件
1 @RequestMapping("fileUpload_stream")
2 @ResponseBody
3 public String upFile(HttpServletRequest request, @RequestParam("file_upload") MultipartFile multipartFile){
4 String filePath=Files_Helper_DG.FilesUpload_stream(request,multipartFile,"/filesOut/Upload");
5 return "{"TFMark":"true","Msg":"upload success !","filePath":"" + filePath + ""}";
6 }
方式五：采用ajaxFileUpload.js插件与异步上传的方式上传文件
1 @RequestMapping(value = "fileUpload_ajax",method = RequestMethod.POST,produces = {"application/json;charset=UTF-8"})
2 @ResponseBody
3 public String fileUpload_ajax(HttpServletRequest request, @RequestParam("file_AjaxFile") MultipartFile multipartFile) {
4 //调用保存文件的帮助类进行保存文件，并返回文件的相对路径
5 String filePath = Files_Utils_DG.FilesUpload_transferTo_spring(request, multipartFile, "/files/upload");
6 return "{'TFMark':'true','Msg':'upload success !','filePath':'" + filePath + "'}";
7 }
上述方法需要 ajaxfileupload.js 插件的支持,该插件
多文件上传（其实是将上面的 MultipartFile 写成数组形式）
1 @RequestMapping(value = "fileUpload_spring_list") 2 @ResponseBody 3 public String fileUpload_spring_list(HttpServletRequest request, @RequestParam("file_upload") MultipartFile[] multipartFile) { 4 //判断file数组不能为空并且长度大于0 5 if (multipartFile != null && multipartFile.length > 0) { 6 //循环获取file数组中得文件 7 try { 8 for (int i = 0; i < multipartFile.length; i++) { 9 MultipartFile file = multipartFile[i]; 10 //保存文件 11 String fileName = Files_Helper_DG.FilesUpload_transferTo_spring(request, file, "/filesOut/Upload"); 12 System.out.println(fileName); 13 } 14 return "{"TFMark":"true","Msg":"upload success !"}"; 15 } catch (Exception ee) { 16 return "{"TFMark":"false","Msg":"参数传递有误！"}"; 17 } 18 } 19 return "{"TFMark":"false","Msg":"参数传递有误！"}"; 20 }
下面我们进行测试：
首先在webapp下新建文件夹目录/files/download，并且新建一个/Views/FileUpload/FileUpload.jsp
注意文件目录结构以及目录层次！！！
FileUpload.jsp代码如下
1 <%@ page contentType="text/html;charset=UTF-8" language="java" %>
2 <%
3 String path = request.getContextPath();
4 String basePath = request.getScheme() + "://" + request.getServerName() + ":" + request.getServerPort() + path + "/";
5 %>
6 <html>
7 <head>
8 <base href="<%=basePath%>">
9 <title>fileUpload</title>
10 <script src="<%=basePath%>scripts/jquery-1.11.1.js"></script>
11 <script src="<%=basePath%>scripts/ajaxfileupload.js"></script>
12 </head>
13 <body>
14 <h3>文件上传</h3><br>
15
16 <h3>采用 fileUpload_multipartFile ， file.transferTo 来保存上传的文件</h3>
17 <form name="form1" action="/FileUpload/fileUpload_multipartFile" method="post" enctype="multipart/form-data">
18 <input type="file" name="file_upload">
19 <input type="submit" value="upload"/>
20 </form>
21 <hr>
22
23 <h3>采用 fileUpload_multipartRequest file.transferTo 来保存上传文件</h3>
24 <form name="form2" action="/FileUpload/fileUpload_multipartRequest" method="post" enctype="multipart/form-data">
25 <input type="file" name="file_upload">
26 <input type="submit" value="upload"/>
27 </form>
28 <hr>
29
30 <h3>采用 CommonsMultipartResolver file.transferTo 来保存上传文件</h3>
31 <form name="form3" action="/FileUpload/fileUpload_CommonsMultipartResolver" method="post" enctype="multipart/form-data">
32 <input type="file" name="file_upload">
33 <input type="submit" value="upload"/>
34 </form>
35 <hr>
36
37 <h3>通过流的方式上传文件</h3>
38 <form name="form4" action="/FileUpload/fileUpload_stream" method="post" enctype="multipart/form-data">
39 <input type="file" name="file_upload">
40 <input type="submit" value="upload"/>
41 </form>
42 <hr>
43
44 <h3>通过ajax插件 ajaxfileupload.js 来异步上传文件</h3>
45 <form name="form5" action="/" method="post" enctype="multipart/form-data">
46 <input type="file" id="file_AjaxFile" name="file_AjaxFile">
47 <input type="button" value="upload" onclick="fileUploadAjax()"/><span id="sp_AjaxFile"></span><br><br>
48 上传进度：<span id="sp_fileUploadProgress">0%</span>
49 </form>
50 <script type="text/javascript">
51 function fileUploadAjax() {
52 if ($("#file_AjaxFile").val().length > 0) {
53 progressInterval=setInterval(getProgress,500);
54 $.ajaxFileUpload({
55 url: '/FileUpload/fileUpload_ajax', //用于文件上传的服务器端请求地址
56 type: "post",
57 secureuri: false, //一般设置为false
58 fileElementId: 'file_AjaxFile', //文件上传空间的id属性 <input type="file" id="file1" name="file" />
59 dataType: 'application/json', //返回值类型 一般设置为json
60 success: function (data) //服务器成功响应处理函数
61 {
62 var jsonObject = eval('(' + data + ')');
63 $("#sp_AjaxFile").html(" Upload Success ！ filePath:" + jsonObject.filePath);
64 },
65 error: function (data, status, e)//服务器响应失败处理函数
66 {
67 alert(e);
68 }
69 });//end ajaxfile
70 }
71 else {
72 alert("请选择文件!");
73 }
74 }
75 var progressInterval = null;
76 var i=0;
77 var getProgress=function (){
78 $.get("/FileUpload/fileUploadprogress",
79 {},
80 function (data) {
81 $("#sp_fileUploadProgress").html(i+++data);
82 if(data==100||i==100)
83 clearInterval(progressInterval);
84 }
85 );
86 }
87 </script>
88 <hr>
89
90 <h3>多文件上传 采用 MultipartFile[] multipartFile 上传文件方法</h3>
91 <form name="form5" action="/FileUpload/fileUpload_spring_list" method="post" enctype="multipart/form-data">
92 <input type="file" name="file_upload">
93 <input type="file" name="file_upload">
94 <input type="file" name="file_upload">
95 <input type="submit" value="upload"/>
96 </form>
97 <hr>
98
99 <h3>通过 a 标签的方式进行文件下载</h3><br>
100 <a href="<%=basePath%>filesOut/Download/mst.txt">通过 a 标签下载文件 mst.txt</a>
101 <hr>
102 <h3>通过 Response 文件流的方式下载文件</h3>
103 <a href="/FileUpload/fileDownload_servlet">通过 文件流 的方式下载文件 mst.txt</a>
104
105 </body>
106 </html>
这里一定要记得在spring-servlet.xml里面配置访问静态路径方法->下面我附上spring-servlet.xml
1 <?xml version="1.0" encoding="UTF-8"?> 2 <beans xmlns="http://www.springframework.org/schema/beans" 3 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 4 xmlns:context="http://www.springframework.org/schema/context" 5 xmlns:mvc="http://www.springframework.org/schema/mvc" 6 xsi:schemaLocation="http://www.springframework.org/schema/beans 7 http://www.springframework.org/schema/beans/spring-beans-3.1.xsd 8 http://www.springframework.org/schema/context 9 http://www.springframework.org/schema/context/spring-context-3.1.xsd 10 http://www.springframework.org/schema/mvc 11 http://www.springframework.org/schema/mvc/spring-mvc-3.1.xsd"> 12 13 <!-- 启动注解驱动的Spring MVC功能，注册请求url和注解POJO类方法的映射--> 14 <mvc:annotation-driven > 15 16 </mvc:annotation-driven> 17 18 <!-- 启动包扫描功能，以便注册带有@Controller、@service、@repository、@Component等注解的类成为spring的bean --> 19 <context:component-scan base-package="HelloSpringMVC.controller" /> 20 <!-- 对模型视图名称的解析，在请求时模型视图名称添加前后缀 --> 21 <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver"> 22 <property name="viewClass" value="org.springframework.web.servlet.view.JstlView"/> 23 <property name="prefix" value="/"/> <!-- 前缀 --> 24 <property name="suffix" value=".jsp"/> <!-- 后缀 --> 25 </bean> 26 <!-- 访问静态文件（jpg,js,css）的方法 --> 27 <mvc:resources location="/files/" mapping="/files/**" /> 28 <mvc:resources location="/scripts/" mapping="/scripts/**" /> 29 <mvc:resources location="/styles/" mapping="/styles/**" /> 30 <mvc:resources location="/Views/" mapping="/Views/**" /> 31 32 <!-- 多部分文件上传 需配置MultipartResolver处理器--> 33 <bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver"> 34 <property name="maxUploadSize" value="104857600" /> 35 <property name="maxInMemorySize" value="4096" /> 36 <property name="defaultEncoding" value="UTF-8"></property> 37 </bean> 38 <!-- SpringMVC在超出上传文件限制时,会抛出org.springframework.web.multipart.MaxUploadSizeExceededException --> 39 <!-- 该异常是SpringMVC在检查上传的文件信息时抛出来的,而且此时还没有进入到Controller方法中 --> 40 <bean id="exceptionResolver" class="org.springframework.web.servlet.handler.SimpleMappingExceptionResolver"> 41 <property name="exceptionMappings"> 42 <props> 43 <!-- 遇到MaxUploadSizeExceededException异常时,自动跳转到/WEB-INF/jsp/error_fileupload.jsp页面 --> 44 <prop key="org.springframework.web.multipart.MaxUploadSizeExceededException">error_fileupload</prop> 45 </props> 46 </property> 47 </bean> 48 </beans>
然后我们运行tomcat进入http://localhost:8080/Views/FileUpload/FileUpload.jsp
打开后，页面如下：
我们依次选择文件->
共八个文件！
然后依次点击upload按钮，进行文件的上传->
可见，六种上传都已经执行成功！下面我们打开文件目录查看一下上传的文件->
一共八个文件！证明所有文件都上传成功了！
二、文件下载
在控制器类 FileUploadController里面继续添加代码->
1 @RequestMapping(value = "fileDownload_servlet")
2 public void fileDownload_servlet(HttpServletRequest request, HttpServletResponse response) {
3 Files_Helper_DG.FilesDownload_servlet(request,response,"/filesOut/Download/mst.txt");
4 }
这里调用了帮助类 Files_Helper_DG.FilesDownload_servlet(request,response,"/filesOut/Download/mst.txt");
然后我们进行测试->
前面我们新建的文件夹/files/download，在里面放一个文件mst.txt,代码访问的就是这个文件！
然后是我们FileUpload.jsp,前面已经拷贝过了这段代码->
1 <h3>通过 a 标签的方式进行文件下载</h3><br> 2 <a href="<%=basePath%>filesOut/Download/mst.txt">通过 a 标签下载文件 mst.txt</a> 3 <hr> 4 <h3>通过 Response 文件流的方式下载文件</h3> 5 <a href="/FileUpload/fileDownload_servlet">通过 文件流 的方式下载文件 mst.txt</a>
首先是第一种直接访问文件目录，此方式有缺陷，暴露了项目文件结构，造成安全隐患！
点击便可下载！（如果浏览器可以读取文件，则会直接浏览器打开，我们可以右键->链接另存为选择路径保存）
然后我们点击第二种下载方式->实际项目中，我们应该优先选择第二种方式，提高了安全性！
从服务器直接下载到浏览器默认的保存文件目录！（本人在F:）
到此，我们的 spring mvc 文件上传下载已经实现！
本文为七小站主原创作品，转载请注明出处：http://www.cnblogs.com/qixiaoyizhan/ 且在文章页面明显位置给出原文链接，否则保留追究法律责任的权利。
另外安利一个博主的个人网站http://qixiao123.cn/ 欢迎大家访问！