@Override
  public OperationCallable<
          AsyncBatchAnnotateFilesRequest, AsyncBatchAnnotateFilesResponse, OperationMetadata>
      asyncBatchAnnotateFilesOperationCallable() {
    return asyncBatchAnnotateFilesOperationCallable;
  }
Constructs an instance of HttpJsonImageAnnotatorStub, 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-vision/google-cloud-vision/src/main/java/com/google/cloud/vision/v1p2beta1/stub/HttpJsonImageAnnotatorStub.java