责任链模式和php实现

<?php//申请类,header("Content-type:text/html;Charset=utf-8");class Request{    public $name;    public $requestContent;    public $num;    public $reason;    function __construct($name,$requestContent,$reason,$num){        $this->name = $name;        $this->requestContent = $requestContent;        $this->reason = $reason;        $this->num = $num;    }}//抽象处理类，定义处理者具有的公共属性和具体处理类需要实现的接口abstract class AbstractManager{    protected $name;   //姓名    protected $position;  //职位    protected $head;  //上司    function __construct($name,$position){        $this->name = $name;        $this->position = $position;    }     //设置上司    function setHead(AbstractManager $head){        $this->head = $head;    }    //处理申请    abstract function handleRequest(Request $request);}//具体处理类，经理,可以处理不多于7天的假期和不多于1000元的加薪请求class Director extends AbstractManager{    function __construct($name,$position){        parent::__construct($name,$position);    }        //处理申请    function handleRequest(Request $request){         if(($request->requestContent == "请假" && $request->num <7)||($request->requestContent == "加薪" && $request->num <1000) ){              return $request->name."的".$request->requestContent."请求已被".$this->name."批准.";         }else{  //超过处理权限转给上级总监处理            if(isset($this->head)){                return $this->head->handleRequest($request);            }         }    }}//具体处理类，总监,可以处理不多于15天的假期和不多于2000元的加薪请求class Majordomo extends AbstractManager{    function __construct($name,$position){        parent::__construct($name,$position);    }        //处理申请    function handleRequest(Request $request){         if(($request->requestContent == "请假" && $request->num <15)||($request->requestContent == "加薪" && $request->num <2000) ){              return $request->name."的".$request->requestContent."请求已被".$this->name."批准.";         }else{  //超过处理权限转给上级总经理处理            if(isset($this->head)){                return $this->head->handleRequest($request);            }         }    }}//具体处理类，总经理,可以处理请假和加薪请求class GeneralManager extends AbstractManager{    function __construct($name,$position){        parent::__construct($name,$position);    }        //处理申请    function handleRequest(Request $request){         if(($request->requestContent == "请假" && $request->num < 30)||($request->requestContent == "加薪" && $request->num <5000) ){              return $request->name."的".$request->requestContent."请求已被".$this->name."批准.";         }else{  //没有上级            return $request->name."的".$request->requestContent."请求已被".$this->name."否决！";         }    }}//测试$generalManagerWang = new GeneralManager("王五","总经理");$majordomoLi = new Majordomo("李四","总监");$majordomoLi->setHead($generalManagerWang);$directZhang = new Director("张三","经理");$directZhang->setHead($majordomoLi);$request = new Request("叶良辰","请假","如果你有问题，可以随时找我，良辰就喜欢对自以为是的人出手",100);$result = $directZhang->handleRequest($request);  //叶良辰的请假请求已被王五否决！echo $result;