@Override
    public KTable<Windowed<K>, Long> count() {
        return count(NamedInternal.empty());
    }
@Test
    public void shouldCountSlidingWindows() {
        final MockApiProcessorSupplier<Windowed<String>, Long, Void, Void> supplier = new MockApiProcessorSupplier<>();
        windowedStream
            .count()
            .toStream()
            .process(supplier);

        try (final TopologyTestDriver driver = new TopologyTestDriver(builder.build(), props)) {
            processData(driver);
        }
        assertThat(
            supplier.theCapturedProcessor().lastValueAndTimestampPerKey()
                .get(new Windowed<>("1", new TimeWindow(0L, 100L))),
            equalTo(ValueAndTimestamp.make(1L, 100L)));
        assertThat(
            supplier.theCapturedProcessor().lastValueAndTimestampPerKey()
                .get(new Windowed<>("1", new TimeWindow(101L, 201L))),
            equalTo(ValueAndTimestamp.make(1L, 150L)));
        assertThat(
            supplier.theCapturedProcessor().lastValueAndTimestampPerKey()
                .get(new Windowed<>("1", new TimeWindow(50L, 150L))),
            equalTo(ValueAndTimestamp.make(2L, 150L)));
        assertThat(
            supplier.theCapturedProcessor().lastValueAndTimestampPerKey()
                .get(new Windowed<>("1", new TimeWindow(400L, 500L))),
            equalTo(ValueAndTimestamp.make(1L, 500L)));
        assertThat(
            supplier.theCapturedProcessor().lastValueAndTimestampPerKey()
                .get(new Windowed<>("2", new TimeWindow(100L, 200L))),
            equalTo(ValueAndTimestamp.make(2L, 200L)));
        assertThat(
            supplier.theCapturedProcessor().lastValueAndTimestampPerKey()
                .get(new Windowed<>("2", new TimeWindow(50L, 150L))),
            equalTo(ValueAndTimestamp.make(1L, 150L)));
        assertThat(
            supplier.theCapturedProcessor().lastValueAndTimestampPerKey()
                .get(new Windowed<>("2", new TimeWindow(151L, 251L))),
            equalTo(ValueAndTimestamp.make(1L, 200L)));
    }