Endless autoscrolling for viewPager

AutoScrollHelper.java

public static ObjectAnimator scrollDownSmoothlyIndefinitely(@NonNull WeakReference<NestedScrollView> scrollViewRef, int scrollingDuration) {
        NestedScrollView scrollView = scrollViewRef.get();
        if (scrollView != null) {

            final ObjectAnimator animScrollDown = ObjectAnimator.ofInt(scrollView, "scrollY",
                    scrollView.getChildAt(0).getHeight());

            animScrollDown.setInterpolator(new LinearInterpolator());
            animScrollDown.setDuration(scrollingDuration);

            final ObjectAnimator animScrollToTop = ObjectAnimator.ofInt(scrollView, "scrollY",
                    0);
            animScrollToTop.setDuration(500);
            animScrollDown.addListener(new Animator.AnimatorListener() {
                @Override
                public void onAnimationStart(Animator animator) {

                }

                @Override
                public void onAnimationEnd(Animator animator) {
                    if (!animScrollToTop.isStarted()) {
                        animScrollToTop.start();
                    }
                }

                @Override
                public void onAnimationCancel(Animator animator) {

                }

                @Override
                public void onAnimationRepeat(Animator animator) {

                }
            });

            animScrollToTop.addListener(new Animator.AnimatorListener() {
                @Override
                public void onAnimationStart(Animator animator) {

                }

                @Override
                public void onAnimationEnd(Animator animator) {

                    if (!animScrollDown.isStarted()) {
                        animScrollDown.start();
                    }
                }

                @Override
                public void onAnimationCancel(Animator animator) {
                }

                @Override
                public void onAnimationRepeat(Animator animator) {
                }
            });


            if (!animScrollDown.isStarted()) {
                animScrollDown.start();
            }
            return animScrollDown;
        }
        return null;
    }