public static <T, T_RESULT_PAGE extends ResultPage<T>> Collector<T, List<T>, T_RESULT_PAGE> collector(
            final PageRequest pageRequest,
            final BiFunction<List<T>, PageResponse, T_RESULT_PAGE> resultPageFactory) {

        return createCollector(pageRequest, resultPageFactory);
    }
Creates a collector that builds a sub class of a ResultPage, e.g.
.collect(ListConfigResponse.collector(pageRequest, ListConfigResponse::new));
stroom-util/src/main/java/stroom/util/ResultPageFactory.java