PHP实现基于状态的责任链审批模式详解(2)

<?php
abstract class manager
{
  public $subject; //加载专题内容
  public $mystate=0; //当前状态，这个很重要
  public $leader=false; //重要，设置自己的领导是谁
  public $myname = ''; //当前审批者的名字
  /**
   * 设置领导是谁
   * @param $leader
   */
  public function setLeader($leader)
  {
    $this->leader = $leader; //形成责任链的关键
  }
  public function __construct()
  {
    $str = file_get_contents(__DIR__.'/subject.json');
    $this->subject = json_decode($str);
  }
  public function step($msg)
  {
    //很重要，代表审批
    //只有当subject的state和自己的mystate相等是才会处理
    if ($this->subject->state == $this->mystate){ //代表当前是自己要处理的
      //在这执行审批通过的 具体
      echo $msg . '审批制是：'.$this->myname;
      //判断自己的是否有领导，如果有把控制权交给领导
      if ($this->leader){
        $this->subject->state = $this->leader->mystate; //交控制权
        file_put_contents(__DIR__.'/subject.json',json_encode($this->subject)); //保存状态
      }else{
        echo '审批已经结束';
      }
    }else{
      if ($this->leader){ //leader就是维护整个类的 链
        //让自己的领导去审批
        $this->leader->step($msg);
      }
    }
  }
}

<?php
class BusinessLeader extends manager
{
  public $myname = '商务部领导';
  public $mystate = 0;
}

<?php
class ProductLeader extends manager
{
  public $myname = '商品部领导';
  public $mystate = 1;
}

<?php
class LastLeader extends manager
{
  public $myname = '终极领导';
  public $mystate = 2;
}

if (isset($_GET['step'])){ //进入领导审批阶段了
  //这里面最关键是
   //1.确定第一个领导是谁
   //2. 要维护各个领导直接的关系，
   require ('manager.php');
   require ('BusinessLeader.php');
   require ('ProductLeader.php');
   require ('LastLeader.php');
   $businessLeader = new BusinessLeader();
   $productLeader = new ProductLeader();
   $lastLeader = new LastLeader();
   //下面还是维护关系
   $businessLeader->setLeader($productLeader);
   $productLeader->setLeader($lastLeader);
   $businessLeader->step('审批通过');
}