@Override
            public ApiFuture<ListUsableWorkstationConfigsPagedResponse> getFuturePagedResponse(
                UnaryCallable<
                        ListUsableWorkstationConfigsRequest, ListUsableWorkstationConfigsResponse>
                    callable,
                ListUsableWorkstationConfigsRequest request,
                ApiCallContext context,
                ApiFuture<ListUsableWorkstationConfigsResponse> futureResponse) {
              PageContext<
                      ListUsableWorkstationConfigsRequest,
                      ListUsableWorkstationConfigsResponse,
                      WorkstationConfig>
                  pageContext =
                      PageContext.create(
                          callable,
                          LIST_USABLE_WORKSTATION_CONFIGS_PAGE_STR_DESC,
                          request,
                          context);
              return ListUsableWorkstationConfigsPagedResponse.createAsync(
                  pageContext, futureResponse);
            }
The default scopes of the service.
java-workstations/google-cloud-workstations/src/main/java/com/google/cloud/workstations/v1beta/stub/WorkstationsStubSettings.java