@Override
  public OperationCallable<
          ReactivateSubscriptionRequest, Subscription, ReactivateSubscriptionMetadata>
      reactivateSubscriptionOperationCallable() {
    return reactivateSubscriptionOperationCallable;
  }
Constructs an instance of GrpcSubscriptionsServiceStub, 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-workspaceevents/google-cloud-workspaceevents/src/main/java/com/google/apps/events/subscriptions/v1/stub/GrpcSubscriptionsServiceStub.java