PHP使用标准库spl实现的观察者模式示例

<?php/** * Created by PhpStorm. * User: evolution * Date: 14-12-27 * Time: 下午5:50 */class Login implements SplSubject {  private $storage;  public $status;  public $ip;  const LOGIN_ACCESS = 1;  const LOGIN_WRONG_PASS = 2;  const LOGIN_USER_UNKNOWN = 3;  function __construct(){    $this->storage = new SplObjectStorage();  }  function attach (SplObserver $observer) {    $this->storage->attach($observer);  }  function detach(SplObserver $observer){    $this->storage->detach($observer);  }  function notify(){    foreach ($this->storage as $obs) {      $obs->update($this);    }  }  /**   * @author jichao.wang   * 执行登陆   */  function handleLogin()  {    $ip = rand(1,100);    switch (rand(1, 3)) {      case 1:        $this->setStatus(self::LOGIN_ACCESS, $ip);        $ret = true;        break;      case 2:        $this->setStatus(self::LOGIN_WRONG_PASS, $ip);        $ret = false;        break;      case 3:        $this->setStatus(self::LOGIN_USER_UNKNOWN, $ip);        $ret = false;        break;    }    /**     * handle event     */    $this->notify();    return $ret;  }  /**   * @param $status   * @author jichao.wang   * set login status   */  function setStatus($status,$ip)  {    $this->status = $status;    $this->ip = $ip;  }  /**   * @return mixed   * @author jichao.wang   * get login status   */  function getStatus()  {    return $this->status;  }}/** * 只针对登陆的贯观察者 * Class LoginObserver */abstract class LoginObserver implements SplObserver {  private $login;  function __construct(Login $login){    $this->login = $login;    $login->attach($this);  }  /**   * 对外统一的访问点   * @param SplSubject $subject   */  function update( SplSubject $subject ){    if($subject === $this->login){      $this->doUpdate($subject);    }  }  abstract function doUpdate( Login $login );}/** * Class EmailObserver */class EmailObserver extends LoginObserver{  //不同功能的观察者实现不同的功能  function doUpdate( Login $login ){    $status = $login->getStatus();    if($status == Login::LOGIN_ACCESS){//      $this->sendMail('用户ip:'.$observable->ip.'登陆成功!');      echo __CLASS__.'用户ip:'.$login->ip.'登陆成功!'.'------------------';    }    if($status == Login::LOGIN_WRONG_PASS){//      $this->sendMail('用户ip:'.$observable->ip.'登陆失败，密码错误!');      echo __CLASS__.'用户ip:'.$login->ip.'登陆失败，密码错误!'.'------------------';    }    if($status == Login::LOGIN_USER_UNKNOWN){//      $this->sendMail('用户ip:'.$observable->ip.'登陆失败，无此用户!');      echo __CLASS__.'用户ip:'.$login->ip.'登陆失败，无此用户!'.'------------------';    }  }}//实例化登陆信息$login = new Login();//实现发邮件观察者new EmailObserver($login);//开始登陆$login->handleLogin();