@Override
    public <W extends Window> TimeWindowedCogroupedKStream<K, VOut> windowedBy(final Windows<W> windows) {
        Objects.requireNonNull(windows, "windows can't be null");
        return new TimeWindowedCogroupedKStreamImpl<>(
            windows,
            builder,
            subTopologySourceNodes,
            name,
            aggregateBuilder,
            graphNode,
            groupPatterns);
    }
@Test
    public void shouldNotHaveNullWindowOnWindowedBySliding() {
        assertThrows(NullPointerException.class, () -> cogroupedStream.windowedBy((SlidingWindows) null));
    }