آموزش اپراتور یا عملگر Buffer در RxJava

Observable integerObservable = Observable.just(1, 2, 3, 4,
         5, 6, 7, 8, 9);
integerObservable.subscribeOn(Schedulers.io())
         .observeOn(AndroidSchedulers.mainThread())
         .buffer(3)
         .subscribe(new Observer>() {
             @Override
             public void onSubscribe(Disposable d) {   
     }

        @Override
        public void onNext(List<Integer> integers) {
            Log.d(TAG, "onNext");
            for (Integer integer : integers) {
                Log.d(TAG, "Item: " + integer);
            }
        }

        @Override
        public void onError(Throwable e) {

        }

        @Override
        public void onComplete() {
            Log.d(TAG, "All items emitted!");
        }
    });