public function mergeFromString($s) {
    // Adds in data from the string 's'.
    // Raises a ProtocolBufferDecodeError if, after successfully merging
    // in the contents of 's', this protocol message is still not initialized.
    $this->mergePartialFromString($s);
    $uninitialized = $this->checkInitialized();
    if ($uninitialized !== null) {
      throw new ProtocolBufferDecodeError(
        "Not initialized: " . $uninitialized);
    }
  }