FromObservable.java

Observable.fromArray(new String[]{"A", "B", "C", "D", "E", "F"})
                .subscribe(new Observer<String>() {
                    @Override
                    public void onSubscribe(Disposable d) {

                    }

                    @Override
                    public void onNext(String string) {
                        System.out.println("onNext: " + string);
                    }

                    @Override
                    public void onError(Throwable e) {
                        System.out.println("onError: " + e.getMessage());
                    }

                    @Override
                    public void onComplete() {

                    }
                });