@Override
    public Processor<K, Change<V>, K, Change<VOut>> get() {
        return new KTableTransformValuesProcessor(transformerSupplier.get());
    }
@Test
    public void shouldThrowOnGetIfSupplierReturnsNull() {
        final KTableTransformValues<String, String, String> transformer =
            new KTableTransformValues<>(parent, new NullSupplier(), QUERYABLE_NAME);

        try {
            transformer.get();
            fail("NPE expected");
        } catch (final NullPointerException expected) {
            // expected
        }
    }