@Override
  public UnaryCallable<ListCustomClassesRequest, ListCustomClassesResponse>
      listCustomClassesCallable() {
    return listCustomClassesCallable;
  }
Constructs an instance of HttpJsonSpeechStub, using the given settings. This is protected so
that it is easy to make a subclass, but otherwise, the static factory methods should be
preferred.
java-speech/google-cloud-speech/src/main/java/com/google/cloud/speech/v2/stub/HttpJsonSpeechStub.java