Rx.java

Flowable<String> f = Flowable.just("Hello");
Disposable d1 = f.subscribeWith(new DisposableSubscriber<String>() { … });

Observable<String> o = Observable.just("Hello");
Disposable d2 = o.subscribeWith(new DisposableObserver<String>() { … });

Maybe<String> m = Maybe.just("Hello");
Disposable d3 = m.subscribeWith(new DisposableMaybeObserver<String>() { … });

Single<String> s = Single.just("Hello");
Disposable d4 = s.subscribeWith(new DisposableSingleObserver<String>() { … });

Completable c = Completable.completed();
Disposable d5 = c.subscribeWith(new DisposableCompletableObserver<String>() { … });

CompositeDisposable a=new CompositeDisposable();
a.add(o.subscribeWith(new DisposableObserver<String>() {…});
a.add(f.subscribeWith(new DisposableSubscriber<String>() {…});

          
@Override
protected void onDestroy() {
  super.onDestroy();
  d.dispose();
  s.clear();
}