code: public static HttpRequestor.Response startPostRaw(DbxRequestConfig requestConfig,
                                                        String sdkUserAgentIdentifier,
                                                        String host,
                                                        String path,
                                                        byte[] body,
                                                        /*@Nullable*/List<HttpRequestor.Header> headers)
          throws NetworkIOException {
          String uri = buildUri(host, path);
  
          headers = copyHeaders(headers);
          headers = addUserAgentHeader(headers, requestConfig, sdkUserAgentIdentifier);
          headers.add(new HttpRequestor.Header("Content-Length", Integer.toString(body.length)));
  
          try {
              HttpRequestor.Uploader uploader = requestConfig.getHttpRequestor().startPost(uri, headers);
              try {
                  uploader.upload(body);
                  return uploader.finish();
              } finally {
                  uploader.close();
              }
          } catch (IOException ex) {
              throw new NetworkIOException(ex);
          }
      }
docs: Convenience function for making HTTP POST requests.  Like startPostNoAuth but takes byte[] instead of params.