PHP物件導向設計模式-8.2降低耦合樣本____PHP

<?php/** * Created by PhpStorm. * User: 老魯 * Date: 2018/3/16 * Time: 21:48 */class Regitsration{    public function regist(Lesson $lesson)    {        //處理課程        //通知        $notifierObj = Notifier::getNotifier();        $notifierObj->inform();    }}abstract class Notifier{    static function getNotifier()    {        //根據需要和條件設定不同的返回對象        $num = rand(1,2);        if ($num == 1) {            return new TextNotifier();        } elseif ($num == 2){            return new MailNotifier();        }    }}class TextNotifier extends Notifier{    public function inform()    {        return 'TextInform';    }}class MailNotifier extends Notifier{    public function inform()    {        return 'MailInform';    }}