docs: public String uploadFile(byte[] file, String ext, Map<String, String> metaInfo) {
          String path = "";
          TrackerServer trackerServer = null;
          StorageClient1 storageClient1 = null;
          try {
              trackerServer = fastDfsClientPool.borrowObject();
              storageClient1 = new StorageClient1(trackerServer, null);
              NameValuePair data[] = null;
              if (Lang.isNotEmpty(metaInfo)) {
                  data = new NameValuePair[metaInfo.size()];
                  int index = 0;
                  for (Map.Entry<String, String> entry : metaInfo.entrySet()) {
                      data[index] = new NameValuePair(entry.getKey(), entry.getValue());
                      index++;
                  }
              }
              path = storageClient1.uploadFile1(file, ext, data);
          } catch (Exception e) {
              throw Lang.makeThrow("[FastdfsService] upload file error : %s", e.getMessage());
          } finally {
              if (trackerServer != null)
                  fastDfsClientPool.returnObject(trackerServer);
              storageClient1 = null;
          }
          return path;
      }