@Override
  public UnaryCallable<ListTracesRequest, ListTracesResponse> listTracesCallable() {
    return listTracesCallable;
  }
Constructs an instance of HttpJsonTraceServiceStub, 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-trace/google-cloud-trace/src/main/java/com/google/cloud/trace/v1/stub/HttpJsonTraceServiceStub.java