@Test
public void as() {

    Flowable.range(1, 5)
    .parallel()
    .as(new ParallelFlowableConverter<Integer, Flowable<Integer>>() {
        @Override
        public Flowable<Integer> apply(ParallelFlowable<Integer> pf) {
            return pf.sequential();
        }
    })
    .test()
    .assertResult(1, 2, 3, 4, 5);
}