How to skip even lines of a Stream obtained from the Files.lines

Question

In this case just odd lines have meaningful data and there is no character that uniquely identifies those lines. My intention is to get something equivalent to the following

Answer 1

Following the @aioobe algorithm, here's another spliterator-based approach, as proposed by @Holger but more concise, even if less effective.

public static  Stream filterOdd(Stream src) {
    Spliterator iter = src.spliterator();
    AbstractSpliterator res = new AbstractSpliterator(Long.MAX_VALUE, Spliterator.ORDERED)
    {
        @Override
        public boolean tryAdvance(Consumer action) {
            iter.tryAdvance(item -> {});    // discard
            return iter.tryAdvance(action); // use
        }
    };
    return StreamSupport.stream(res, false);
}

Then you can use it like

Stream res = Files.lines(src)
filterOdd(res)
 .map(line -> toDomainObject(line))