Schedulers.io() method creates and returns a Scheduler intended for IO-bound work. Thread pool may extend as needed. Best for I/O intensive operations.
Create the following Java program using any editor of your choice in, say, C:\> RxJava.
import java.util.Random; import io.reactivex.Observable; import io.reactivex.schedulers.Schedulers; public class ObservableTester { public static void main(String[] args) throws InterruptedException { Observable.just("A", "AB", "ABC") .flatMap(v -> getLengthWithDelay(v) .doOnNext(s -> System.out.println("Processing Thread " + Thread.currentThread().getName())) .subscribeOn(Schedulers.io())) .subscribe(length -> System.out.println("Receiver Thread " + Thread.currentThread().getName() + ", Item length " + length)); Thread.sleep(10000); } protected static Observable<Integer> getLengthWithDelay(String v) { Random random = new Random(); try { Thread.sleep(random.nextInt(3) * 1000); return Observable.just(v.length()); } catch (InterruptedException e) { e.printStackTrace(); } return null; } }
Compile the class using javac compiler as follows −
C:\RxJava>javac ObservableTester.java
Now run the ObservableTester as follows −
C:\RxJava>java ObservableTester
It should produce the following output −
Processing Thread RxCachedThreadScheduler-1 Receiver Thread RxCachedThreadScheduler-1, Item length 1 Processing Thread RxCachedThreadScheduler-1 Receiver Thread RxCachedThreadScheduler-1, Item length 2 Processing Thread RxCachedThreadScheduler-1 Receiver Thread RxCachedThreadScheduler-1, Item length 3