@Override
    public synchronized <PS extends Serializer<P>, P> KeyValueIterator<Bytes, byte[]> prefixScan(final P prefix, final PS prefixKeySerializer) {

        final Bytes from = Bytes.wrap(prefixKeySerializer.serialize(null, prefix));
        final Bytes to = Bytes.increment(from);

        return new DelegatingPeekingKeyValueIterator<>(
            name,
            new InMemoryKeyValueIterator(map.subMap(from, true, to, false).keySet(), true)
        );
    }
@Test
    public void shouldThrowNullPointerIfPrefixKeySerializerIsNull() {
        assertThrows(NullPointerException.class, () -> byteStore.prefixScan("bb", null));
    }