@Nullable
    @Override
    public RecordAndPosition<E> next() {
        if (records.hasNext()) {
            recordAndPosition.setNext(records.next());
            return recordAndPosition;
        } else {
            return null;
        }
    }
@Test
    void testExhausted() {
        final IteratorResultIterator<String> iter =
                new IteratorResultIterator<>(Arrays.asList("1", "2").iterator(), 0L, 0L);

        iter.next();
        iter.next();

        assertThat(iter.next()).isNull();
    }