SpringMVC 使用 MultipartFile 实现文件上传

该代码实现了文件上传和文本字段同时传递到后台进行处理的功能。

直接贴代码，中间涉及到的实体类就不贴了，和功能没啥关系的。

Controller

    /**
     * 添加活动
     * 
     * @param req
     * @param file1
     * @param file2
     * @return
     */
    @RequestMapping(value = "/addActivity", method = RequestMethod.POST)
    public JSONObject addActivity(HttpServletRequest req, @RequestParam(value = "file1") MultipartFile file1,
            @RequestParam(value = "file2") MultipartFile file2) {
        logger.info("enter into method addActivity");
        StatusCode statusCode = activityService.addActivity(req, file1, file2);
        return new ResultBuilder<>(statusCode).toJSONObject();
    }

Service

    /**
     * 添加活动
     * @param req
     * @param file1
     * @param file2
     * @return
     */
    public StatusCode addActivity(HttpServletRequest req, MultipartFile file1, MultipartFile file2) {
        try {
            //从request中获取上传的文件
            /*if(file1 == null){
                MultipartHttpServletRequest multipartRequest = (MultipartHttpServletRequest)req;
                file1 = multipartRequest.getFile("file1");
            }
            if(file2 == null){
                MultipartHttpServletRequest multipartRequest = (MultipartHttpServletRequest)req;
                file2 = multipartRequest.getFile("file2");
            }*/
            
            if (file1 == null || file2 == null) {
                logger.info("the file is null");
                return StatusCode.FILE_IS_NULL;
            }
            
            String filepath1 = uploadFile(file1);
            String filepath2 = uploadFile(file2);
            if (filepath1 == null || filepath2 == null) {
                logger.info("the file upload fail");
                return StatusCode.FILE_UPLOAD_FAIL;
            }
            
            String activityname = req.getParameter("activityname");//活动名称
            String winrate = req.getParameter("winrate");//中奖率
            String expectedwinners = req.getParameter("expectedwinners");//预期中奖人数
            String daysnum = req.getParameter("daysnum");//每天首次访问小程序可获得的抽奖次数
            String firstnum = req.getParameter("firstnum");//首次关注公众号可获得的抽奖次数
            String sharelimitnum = req.getParameter("sharelimitnum");//每日分享最多可获得的抽奖次数
            String friendclicknum = req.getParameter("friendclicknum");//每日好友点击最多可获得的抽奖次数
            String ruledesc = req.getParameter("ruledesc");//规则描述
            String starttime = req.getParameter("starttime");//开始时间
            String endtime = req.getParameter("endtime");//结束时间
            String prizename = req.getParameter("prizename");//奖品名称
            String prizeprice = req.getParameter("prizeprice");//奖品价格
            String cardid = req.getParameter("cardid");//卡片ID
            
            if (StringUtils.isNullOrEmpty(activityname) || StringUtils.isNullOrEmpty(expectedwinners) || StringUtils.isNullOrEmpty(daysnum)
                    || StringUtils.isNullOrEmpty(firstnum) || StringUtils.isNullOrEmpty(sharelimitnum) || StringUtils.isNullOrEmpty(friendclicknum)
                    || StringUtils.isNullOrEmpty(ruledesc) || StringUtils.isNullOrEmpty(starttime) || StringUtils.isNullOrEmpty(endtime)
                    || StringUtils.isNullOrEmpty(prizename) || StringUtils.isNullOrEmpty(prizeprice) || StringUtils.isNullOrEmpty(cardid)
                    || StringUtils.isNullOrEmpty(winrate)) {
                logger.info("the paramter is null or empty");
                return StatusCode.REQUEST_PARAM_ERROR;
            }
            
            if (Long.parseLong(starttime) >= Long.parseLong(endtime)) {
                logger.info("the starttime less than or equal to endtime");
                return StatusCode.ACTIVITY_TIME_ERROR;
            }
            
            Activity activity = new Activity();
            activity.setActivityname(activityname);
            activity.setCoverimage(filepath1);
            activity.setThumbnail(filepath2);
            activity.setWinrate(Double.valueOf(winrate));
            activity.setExpectedwinners(Integer.valueOf(expectedwinners));
            activity.setDaysnum(Integer.valueOf(daysnum));
            activity.setFirstnum(Integer.valueOf(firstnum));
            activity.setSharelimitnum(Integer.valueOf(sharelimitnum));
            activity.setFriendclicknum(Integer.valueOf(friendclicknum));
            activity.setRuledesc(ruledesc);
            activity.setStarttime(new Date(Long.parseLong(starttime)));
            activity.setEndtime(new Date(Long.parseLong(endtime)));
            activity.setPrizename(prizename);
            activity.setPrizeprice(Double.valueOf(prizeprice));
            activity.setCardid(Integer.valueOf(cardid));
            
            int result = activityMapper.addActivity(activity);
            if (result != 1) {
                logger.info("add activity fail");
                return StatusCode.ADD_ACTIVITY_FAIL;
            }
        } catch (Exception e) {
            logger.error("add activity error", e);
            return StatusCode.FAIL;
        }
        return StatusCode.SUCCESS;
    }
    
    /**
     * 文件上传
     * @param file
     * @param savepath
     * @return
     */
    public String uploadFile(MultipartFile file){
        String savepath = Constants.UPLOAD_FILE_IMAGE_SAVE_PATH;
        File filedir = new File(savepath);
        //如果文件夹不存在则创建    
        if (!filedir.exists()) {
            logger.info("create directory:{}", savepath);
            try{
                filedir.mkdirs();
            }catch(Exception e){
                logger.error("create directory fail", e);
                return null;
            }
        }
        
        SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMddHHmmss");
        String nowdate = sdf.format(new Date(System.currentTimeMillis()));
        
        String originalfilename = file.getOriginalFilename();
        if (originalfilename == null || !originalfilename.contains(".")) {
            logger.info("file name is error:{}", originalfilename);
            return null;
        }
        String suffix = originalfilename.substring(originalfilename.indexOf("."));
        String filepath = savepath + nowdate + suffix;
        
        File targetFile = new File(filepath);
        try {
            file.transferTo(targetFile);
        } catch (Exception e) {
            logger.error("file upload fail", e);
            return null;
        }
        return filepath;
    }

使用FORM的话需要指定enctype="multipart/form-data"

附上我测试用的form表单

  <form action="http://localhost:8080/activity/addActivity" method="post" enctype="multipart/form-data">
    activityname<input type="text" name="activityname" value="第一个测试活动"/><br>
    expectedwinners<input type="text" name="expectedwinners" value="100"/><br>
    daysnum<input type="text" name="daysnum" value="3"/><br>
    firstnum<input type="text" name="firstnum" value="5"/><br>
    sharelimitnum<input type="text" name="sharelimitnum" value="6"/><br>
    friendclicknum<input type="text" name="friendclicknum" value="7"/><br>
    ruledesc<input type="text" name="ruledesc" value="这里简单描述下规则，自己写啊。"/><br>
    starttime<input type="text" name="starttime" value="1519292136927"/><br>
    endtime<input type="text" name="endtime" value="1519293136927"/><br>
    prizename<input type="text" name="prizename" value="笔记本电脑"/><br>
    prizeprice<input type="text" name="prizeprice" value="5999.56"/><br>
    cardid<input type="text" name="cardid" value="1"/><br>
    <input type="file" name="file1"/><br>
    <input type="file" name="file2"/><br>
    <input type="submit" value="提交"/>
  </form>