Adding a Pool of Threads in a RxJava Flow

I found it by myself!

package radium.rx;import java.util.List;import java.util.Arrays;import java.util.Random;import java.util.concurrent.ExecutorService;import java.util.concurrent.Executors;import java.util.concurrent.TimeUnit;import rx.Observable;import rx.schedulers.Schedulers;public class TryRx {    public static Random RANDOM = new Random();    public static void main(String[] arguments) throws Throwable {        final List<Integer> inputs = Arrays.asList(1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12);        final ExecutorService threadPoolExecutor = Executors.newFixedThreadPool(2);        Iterable<Integer> outputs = Observable.<Integer>from(inputs)                .flatMap((Integer input) -> deferHeavyWeightStuff(input).subscribeOn(Schedulers.from(threadPoolExecutor)))                .toBlocking()            .toIterable();        for (Integer output : outputs) {            System.out.println(output);        }        threadPoolExecutor.shutdown();    }    public static void sleepQuietly(int duration, TimeUnit unit) {        try {            Thread.sleep(unit.toMillis(duration));        } catch (InterruptedException e) {        }    }    public static Observable<Integer> deferHeavyWeightStuff(final int input) {        return Observable.defer(() -> Observable.just(doHeavyWeightStuff(input)));    }    public static int randomInt(int min, int max) {        return RANDOM.nextInt((max - min) + 1) + min;    }    public static int doHeavyWeightStuff(int input) {        sleepQuietly(randomInt(1, 5), TimeUnit.SECONDS);        int output = (int) Math.pow(input, 2);        return output;    }}

Cheers!