使用RestTemplate将本地文件上传到服务器

/**
     * 将本地文件上传到文件系统
     *
     * @param region           用户所在数据中心
     * @param userId           用户id
     * @param targetFolderUuid 目标文件夹的id
     * @param filePath         本地文件路径
     * @return
     */
    public static String uploadFileToFileSystem(String region, String userId, String targetFolderUuid, String filePath) {
        FileSystemResource resource = new FileSystemResource(filePath);
        if (!resource.exists() || Strings.isNullOrEmpty(targetFolderUuid)) {
            return null;
        }
        MultiValueMap<String, Object> param = new LinkedMultiValueMap<>();
        param.add("file", resource);
        param.add("userId", userId);
        param.add("targetFolderUuid", targetFolderUuid);
        try {
            String fileServerIp = getFileServerIp(region);
            ResponseEntity responseEntity = innerTokenAccess(HttpMethod.POST, fileServerIp + UPLOAD_URL, param, MediaType.MULTIPART_FORM_DATA);
            JSONObject jsonObject = JSONObject.fromObject(responseEntity.getBody());
            return jsonObject.getString("fileUuid");
        } catch (Exception e) {
            LOG.info("上传文件到文件系统失败：{}", e.getMessage());
        }
        return null;
    }

/**
     * 使用RestTemplate访问远程接口
     *
     * @param method    方法的请求类型 POST or GET OR ...
     * @param url       请求的url
     * @param obj       请求的参数
     * @param mediaType 头信息类型
     * @return
     * @throws Exception
     */
    public static ResponseEntity innerTokenAccess(HttpMethod method, String url, Object obj, MediaType mediaType) throws Exception {
        LOG.info("访问的链接：" + url);
        RestTemplate restTemplate = new RestTemplate();
        HttpHeaders httpHeaders = new HttpHeaders();
        httpHeaders.setContentType(mediaType);
        HttpEntity httpEntity = new HttpEntity(obj, httpHeaders);
        ResponseEntity result = restTemplate.exchange(url, method, httpEntity, String.class);
        LOG.info("访问接口：" + url + "返回的值为：" + result.getStatusCodeValue());
        return result;
    }