Learning RxJava - Second Edition

doOnSuccess()

Remember that Maybe and Single types do not have an onNext() event, but rather an onSuccess() operator to pass a single emission. The doOnSuccess() operator usage should effectively feel like doOnNext():

import io.reactivex.rxjava3.core.Observable;public class Ch3_59 {    public static void main(String[] args) {        Observable.just(5, 3, 7)              .reduce((total, next) -> total + next)              .doOnSuccess(i -> System.out.println("Emitting: " + i))              .subscribe(i -> System.out.println("Received: " + i));    }}

The output of the preceding code snippet is as follows:

Emitting: 15Received: 15