code: public T get() throws Exception {
      waitForPromiseSuccess();
  
      if (response != null) {
        return response;
      } else {
        if (this.exception instanceof IOException) {
          throw (IOException) this.exception;
        } else if (this.exception instanceof io.netty.handler.timeout.TimeoutException) {
          throw new TimeoutException();
        } else {
          throw new IOException(this.exception);
        }
      }
    }
docs: Get the response. (Blocking)
  
  Use addListener to fetch the value in a non blocking way.
  
  @return the response
  @throws Exception on fail