Thread trong Java

 public void run() {
            while (true) {
                try {
                    Thread.sleep(27);
                    Iterator<Enemy_plane> enemy_planeIterator = enemy_planeVector.iterator();
                    while (enemy_planeIterator.hasNext()) {
                        Enemy_plane enemy_plane = enemy_planeIterator.next();
                        enemy_plane.y += 10;
                        if (enemy_plane.y >= 600) enemy_planeIterator.remove();
                    }
                    Iterator<Bullet> bulletIterator = bulletVector.iterator();
                    while (bulletIterator.hasNext()) {
                        Bullet bullet = bulletIterator.next();
                        bullet.y -= 10;
                        if (bullet.y <= 110) bulletIterator.remove();
                    }
                    repaint();
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }
    }

Các bác cho em hỏi có cách nào để trễ đoạn

 Iterator<Enemy_plane> enemy_planeIterator = enemy_planeVector.iterator();
                    while (enemy_planeIterator.hasNext()) {
                        Enemy_plane enemy_plane = enemy_planeIterator.next();
                        enemy_plane.y += 10;
                        if (enemy_plane.y >= 600) enemy_planeIterator.remove();
                    } 

thêm 1s không ạ?