疑问求解

服务器写入文件

现在有这样一段代码

    private void saveImgs(MultipartFile[] images, FirePoint firePoint) {
        for (MultipartFile file : images) {
            new Thread(()->{
                try {
                    VideoFireImagePO image = new VideoFireImagePO();
                    String fileName = file.getOriginalFilename();
                    image.setAlarmId(firePoint.getId().toString());
                    image.setFileName(fileName);
                    try {
                        log.info("save img:{}", fileName);
                        String fileFilePath = storagePath + "image/" + fileName;
                        image.setImagePath(fileFilePath);

                        File img = new File(fileFilePath);
                        if (!img.getParentFile().exists()){
                            img.getParentFile().mkdirs();
                        }
                        byte[] bytes = file.getBytes();
                        log.info("save img size:{}", bytes.length);
                        OutputStream out = new FileOutputStream(fileFilePath);
                        out.write(bytes);
                        out.flush();
                        out.close();
                        log.info("save img success: {}", fileName);
                    } catch (IOException e) {
                        log.error("save img error: ", e);
                    }
                    videFireImageMapper.insert(image);
                }catch (Exception e){
                    log.error("saveImgs error: ", e);
                }
            }).start();
        }
    }

往服务器写入文件 首先本地测试没问题 发布服务器就死活写不进去还没报错 路径没问题，文件也上传了 bytes 不为 0 没有权限吗？也没提示啊

有没有大佬帮忙分析下，困扰许久