Future -> Mono

FutureToMono.java

class FutureToMono {

    final ExecutorService executor = Executors.newSingleThreadExecutor();

    <S> Mono<S> mono(final Future<? extends S> future) {
        final MonoProcessor<S> processor = MonoProcessor.create();
        executor.submit(() -> {
            try {
                final S stat = future.get();
                processor.onNext(stat);
                processor.onComplete();
            } catch (InterruptedException | ExecutionException e) {
                processor.onError(e);
            }
        });
        return processor;
    }
}