@Override
    public <VAgg> KTable<K, VAgg> aggregate(final Initializer<VAgg> initializer,
                                        final Aggregator<? super K, ? super V, VAgg> adder,
                                        final Aggregator<? super K, ? super V, VAgg> subtractor,
                                        final Materialized<K, VAgg, KeyValueStore<Bytes, byte[]>> materialized) {
        return aggregate(initializer, adder, subtractor, NamedInternal.empty(), materialized);
    }
@SuppressWarnings("unchecked")
    @Test
    public void shouldThrowNullPointerOnAggregateWhenMaterializedIsNull() {
        assertThrows(NullPointerException.class, () -> groupedTable.aggregate(
            MockInitializer.STRING_INIT,
            MockAggregator.TOSTRING_ADDER,
            MockAggregator.TOSTRING_REMOVER,
            (Materialized) null));
    }