java.lang.ClassCastException: class io.grpc.stub.ClientCalls$BlockingResponseStream cannot be cast to class java.lang.Iterable (io.grpc.stub.ClientCalls$BlockingResponseStream is in unnamed module of loader 'app'; java.lang.Iterable is in module java.base of loader 'bootstrap')

public int lookupResources(
    RelationshipType relationshipType,
    ResourceType resourceType,
    SubjectType subjectType,
    String subjectID
  ) {
    int size = 0;
    PermissionService.LookupResourcesRequest request = PermissionService
      .LookupResourcesRequest.newBuilder()
      .setConsistency(
        PermissionService.Consistency.newBuilder().setMinimizeLatency(true).build()
      )
      .setResourceObjectType(resourceType.getResourceType())
      .setPermission( relationshipType.getRelationshipType())
      .setSubject(
        Core
          .SubjectReference.newBuilder()
          .setObject(
            Core
              .ObjectReference.newBuilder()
              .setObjectType(subjectType.getSubjectType())
              .setObjectId(subjectID)
              .build()
          )
          .build()
      )
      .build();

    try {

     Iterator<LookupResourcesResponse> response = this.getPermissionsService().lookupResources(request);
     size = Iterables.size((Iterable<?>) response);
      System.out.println("result: " + size);
    } catch (Exception exception) {
      exception.printStackTrace();
    }

    return size;
  }