Using CountDownLatch with RxJava

countdownlatch_rxjava.java

import io.reactivex.Observable;
import io.reactivex.schedulers.Schedulers;
import java.util.concurrent.CountDownLatch;

public class Launcher {
    public static void main(String[] args) {

        Observable<Integer> source = Observable.range(1,10);

        CountDownLatch latch = new CountDownLatch(1);

        source.map(i -> i * 100)
                .doOnNext(i -> System.out.println("Emitting " + i
                        + " on thread " + Thread.currentThread().getName()))
                .observeOn(Schedulers.computation())
                .map(i -> i * 10)
                .subscribe(i -> System.out.println("Received " + i + " on thread "
                        + Thread.currentThread().getName()),
                        Throwable::printStackTrace,
                        latch::countDown
                );

        try {
            latch.await();
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }
}