public static Human createHuman() {
        // һ͵
        Human human = null; 
        // ǻжٸʵ࣬ٸ
        List<Class> concreteHumanList = ClassUtils.getAllClassByInterface(Human.class); // ˶
        // ¯Լʼճʲô˾ʲô
        Random random = new Random();
        int rand = random.nextInt(concreteHumanList.size());
        human = createHuman(concreteHumanList.get(rand));
        return human;
    }