springmvc上传下载

上传

导包

    <!--springmvc 上传-->
    <dependency>
        <groupId>commons-fileupload</groupId>
        <artifactId>commons-fileupload</artifactId>
        <version>1.2.2</version>
    </dependency>
    <dependency>
        <groupId>commons-io</groupId>
        <artifactId>commons-io</artifactId>
        <version>2.4</version>
    </dependency>

配置文件

<!--文件上传-->
<bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
    <!--限制文件大小-->
    <property name="maxUploadSize" value="10485760"></property>
    <property name="defaultEncoding" value="UTF-8"></property>
</bean>

jsp页面

<html>
<head>
    <title>上传</title>
</head>
<body>
    <%--使用post请求,enctype="multipart/form-data"--%>
<form action="/upload.do" method="post" enctype="multipart/form-data">
    <label>头像</label><input type="file" name="file"><br>
    <label>用户名</label><input type="text" value="" placeholder="用户名" name="username"><br>
    <label>密码</label><input type="password" value="" placeholder="密码" name="password"><br>
    <input type="submit" value="提交">
</form>
</body>
</html>

controller层

@RequestMapping(value = "/upload.do")
@ResponseBody
public void testUpload(
    HttpServletRequest request,
    HttpServletResponse response,
    User user,
    @RequestParam(value = "file") MultipartFile file)
    throws IOException {
    // 获取用户信息
    System.out.println("用户名");
    System.out.println(user.getUsername());
    System.out.println("密码");
    System.out.println(user.getPassword());
    // 获取文件名
    String filename = file.getOriginalFilename();
    System.out.println(filename);
    // 获取绝对路径
    String upload_Path = request.getRealPath("/upload");
    // 路径处理
    String file_path = upload_Path + "//" + UUID.randomUUID() + filename;
    // 判断路径是否存在如果没有就创建
    File file1 = new File(file_path);
    if (!file1.getParentFile().exists()) {
    file1.getParentFile().mkdirs();
    }
    // 将文件file里的内容复制到file1里
    file.transferTo(file1);
}

下载

jsp页面

 <html>
 <head>
     <title>Title</title>
 </head>
 <body>
 <a href="download.do?filename=f12c1a77-158f-466f-b272-33144f668de3_4Ib-a8g9aA.jpg">下载</a>
 </body>
 </html>

controller层

    @RequestMapping("/download")
public ResponseEntity<byte[]> downloadTest(
    HttpServletRequest request, @RequestParam("filename") String filename, Model model)
    throws IOException {
    filename = new String(filename.getBytes("ISO-8859-1"), "UTF-8");
    // 文件下载路径
    String path = request.getRealPath("/upload/");
    System.out.println("path:" + path);
    File file = new File(path + File.separator + filename);
    HttpHeaders httpHeaders = new HttpHeaders();
    // 解决文件名的乱码问题
    String downloadFileName = new String(filename.getBytes("UTF-8"), "ISO-8859-1");
    System.out.println("downloadFileName" + downloadFileName);
    // 以attachment方式(下载)打开文件
    httpHeaders.setContentDispositionFormData("attachment", downloadFileName);
    // 二进制流数据,常见的文件下载
    httpHeaders.setContentType(MediaType.APPLICATION_OCTET_STREAM);
    return new ResponseEntity<byte[]>(
        FileUtils.readFileToByteArray(file), httpHeaders, HttpStatus.CREATED);
}