解释器模式和php实现

<?php
//环境角色，定义要解释的全局内容
class Expression{
    public $content;
    function getContent(){
        return $this->content;
    }
}

//抽象解释器
abstract class AbstractInterpreter{
    abstract function interpret($content);
}

//具体解释器,实现抽象解释器的抽象方法
class ChineseInterpreter extends AbstractInterpreter{
    function interpret($content){
        switch($content){
            case ‘0‘: echo "没有人";break;
            case "1": echo "一个人";break;
            case "2": echo "二个人";break;
            case "3": echo "三个人";break;
            case "4": echo "四个人";break;
            case "5": echo "五个人";break;
            case "6": echo "六个人";break;
            case "7": echo "七个人";break;
            case "8": echo "八个人";break;
            case "9": echo "九个人";break;
            default:echo "其他";
        }
    }
}
class EnglishInterpterer extends AbstractInterpreter{
    function interpret($content){
         switch($content){
            case ‘0‘: echo "This is nobody";break;
            case "1": echo "This is one people";break;
            case "2": echo "This is two people";break;
            case "3": echo "This is three people";break;
            case "4": echo "This is four people";break;
            case "5": echo "This is five people";break;
            case "6": echo "This is six people";break;
            case "7": echo "This is seven people";break;
            case "8": echo "This is eight people";break;
            case "9": echo "This is nine people";break;
            default:echo "others";
        }
    }
}

//封装好的对具体解释器的调用类,非解释器模式必须的角色
class Interpreter{
     private $interpreter;
     private $content;
     function __construct(){
         $expression = new Expression();
        $this->content = $expression->getContent();
        if($content[0] == "Chinese"){
             $this->interpreter = new ChineseInterpreter();
         }else{
              $this->interpreter = new EnglishInterpreter();
         }
     }
     function execute(){
         $this->interpreter->interpret($this->content);
     }
}

//测试
Expression::$content = array("Chinese",3,2,4,4,5);
$interpreter = new Interpreter();
$interpreter->execute();
Expression::$content = array("English",3,2,4,4,5);
$interpreter = new Interpreter();
$interpreter->execute();
?>