public void showWall() {
        allPosts = new ArrayList<TimedPosts>();

        for (int i = 0; i < this.posts.size(); i++) {
            String newPost = this.name + ": " + this.posts.get(i).getPost();
            Long time = posts.get(i).getTime();
            allPosts.add(new TimedPosts(newPost, time));
        }

        for (User follower : followers) {
            for (TimedPosts post : follower.getPosts()) {
                String newPost = follower.getName() + ": " + post.getPost();
                Long time = post.getTime();
                allPosts.add(new TimedPosts(newPost, time));
            }
        }
        Collections.sort(allPosts, new Comparator<TimedPosts>() {

            @Override
            public int compare(TimedPosts o1, TimedPosts o2) {
                return (int) ((o1.time - o2.time) / 1000000000);
            }
        });

        for (TimedPosts post : allPosts) {
            long elapsedTimeInSec = (System.nanoTime() - post.getTime()) / 1000000000;
            if (elapsedTimeInSec < 60) {
                int elapsedTime = (int) elapsedTimeInSec;
                System.out.println(post.getPost() + "(" + elapsedTime
                        + " seconds ago)");
            } else {
                int elapsedTime = (int) (elapsedTimeInSec / 60);
                System.out.println(post.getPost() + "(" + elapsedTime
                        + " minutes ago)");

            }
        }
    }