java文件上传

以添加轮播图为例：

	/**
     * 添加轮播信息
     *
     * @param request
     * @param file
     * @param carousel
     * @return
     * @throws IOException
     */
    @RequestMapping(value = "/addCarousel")
    public RecycleResult addCarousel(HttpServletRequest request, MultipartFile file, Carousel carousel) throws IOException {
        if (file == null || StringUtils.isBlank(file.getOriginalFilename())){
            RecycleResult.build(500, "文件不能为空");
        }

        String rootPath = ResourceUtils.getURL("").getPath() + "static/upload/";
        File rootFile = new File(rootPath);
        if (!rootFile.exists()) {
            rootFile.mkdirs();
        }
        String realPath = new Date().getTime() + file.getOriginalFilename();
        //存储文件
        File storeFile = new File(rootPath + realPath);

        file.transferTo(storeFile);

        //写入数据库
        carousel.setPhotoPath(realPath);

        if (carousel != null){
            cmsService.addCarousel(carousel);
        }
        return RecycleResult.ok();
    }

LayuiReplay类（其中get、set方法省略）

public class LayuiReplay <T> {
    private int code;
    private String msg;
    private int count;
    private List<T> data;
 
    public LayuiReplay(int code, String msg, int count, List<T> data) {
        this.code = code;
        this.msg = msg;
        this.count = count;
        this.data = data;
    }
 
    public String toJson() {
        Gson gson = new Gson();
        String json = gson.toJson(this);
        return json;
    }
 
    public static <T> String toJson(int count, List<T> data) {
        LayuiReplay<T> replay = new LayuiReplay<>(ReplyCode.OK.getCode(), ReplyCode.OK.getMessage(), count, data);
        return replay.toJson();
    }
}