<form action="upload" method="post" enctype="multipart/form-data">
    <td class="title" width="18%">选择文件：</td>
     <td width="32%"><input type="file" name="Myfile" class="l-text" /></td>
    <input type="submit" value="submit" style="display:none" />
</form>
        
<tr>
    <td class="b_button">
    <td><button id="button" style="margin-top:30px"  class="big_button" >上传</button></td>
    </td>
</tr>

$("#button").click(function(){
    //获取form 表单对象
    var hideForm = $('form');   
      var options = {  
          dataType : "json",  
          beforeSubmit : function() {  
              alert("正在上传");  
          },  
          success : function(result) {  
              alert('成功上传！');  
              window.close();
          },  
          error : function(result) {  
               
          }  
      };  
      //Submit 提交
      hideForm.ajaxSubmit(options); 
  });

/** 
     * @Method: upload 
     * @Description: 数据上传
     * @return ModelAndView 
     * @throws 
     */ 
    @RequestMapping(value = "/upload",method = RequestMethod.POST)
    @ResponseBody
    public void upload(HttpServletRequest request,HttpServletResponse res,String json
           ) throws Exception {
        MultipartFile file = FileRWUtil.parse2MultFile(request, "Myfile");
        FileUploadBo fileUploadBo = JsonUtil.json2Java(json, FileUploadBo.class);
        //获取当前登入人
        Map<String,String> userMaps = (Map<String,String>) request.getSession().getAttribute("user");
        fileUploadBo.setUpUserNo(userMaps.get("name"));
        //如果文件不为空，写入上传路径
           if(!file.isEmpty()) {
               //上传文件路径
               String filename = file.getOriginalFilename();
               String fileName = fileUploadBizc.getFileName(filename);
               long fileSize = (file.getSize())/1024;
               String fileSizeKb = String.valueOf(fileSize);
              //String fileSizeKb = getTransSize(fileSize);
               String fileType =fileUploadBizc.getExtensionName(filename);
               File filepath = new File("/upload",filename);
               String filePathName = String.valueOf(filepath);
               //获取绝对路径
               //String realPath =request.getSession().getServletContext().getRealPath(filePathName);
               //判断路径是否存在，如果不存在就创建一个
               if (!filepath.getParentFile().exists()) { 
                   filepath.getParentFile().mkdirs();
               }
               //将上传文件保存到一个目标文件当中
               file.transferTo(new File("/upload" + File.separator + filename));
               fileUploadBo.setName(fileName);
               fileUploadBo.setFileType(fileType);
               fileUploadBo.setFilePath(filePathName);
               fileUploadBo.setFileSize(fileSizeKb);
               fileUploadBizc.saveFileUplod(fileUploadBo);
           }

3.配置部分

<bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
        <!-- 上传文件大小限制，单位为字节-10Mb -->
        <property name="maxUploadSize">
            <value>10485760</value>
        </property>
        <!-- 请求的编码格式 -->
        <property name="defaultEncoding">
            <value>UTF-8</value>
        </property>
    </bean>

4.注意事项
@RequestParam("Myfile")
和 <td width="32%"><input type="file" name="Myfile" class="l-text" /></td>