Composite_组合模式_PHP语言描述

<?php
	/*
	 * 组合模式定义:将对象组合成树型结构以表示"部分-整体"的层次结构.组合模式使得用户对单个对象和组合对象的使用具有一致性。
	 */

	//抽象的组件对象
	 class Component{
		//输出组件自身的名称
		public function printStruct($preStr){}
		
		//向组件对象中加入组件对象
		public function addChild($component){}
		
		//从组件对象中移除某个组件
		public function removeChild($component){}
		
		//返回某个索引对象的组件对象
		public function getChild($component){}
	}
	
	//叶子类的实现，由于叶子类不具有组件的功能，所以不能使用一些组件的功能
	
	class leaf extends Component{
		private $name = "";
		
		public function __construct($name){
			$this->name = $name;
		}
		
		public function printStruct($preStr){
			echo $preStr."-".$this->name;
		}
		
		public function addChild($component){
			trigger_error("This Object don't use addChild Function!",E_USER_ERROR);
		}
		
		public function removeChild($component){
			trigger_error("This Object don't use removeChild Function!",E_USER_ERROR);
		}
		
		public function getChild($component){
			trigger_error("This Object don't use getChild Function!",E_USER_ERROR);
		}
	}
	
	// 组合对象类,可以包含其他的组合对象或者叶子对象
	class Composite extends Component{
		
		//组件对象数组
		private $componentArr;
		//自身的名称
		private $name;
		
		public function __construct($name){
			$this->name = $name;
		}
		
		public function addChild($component){
			//延迟初始化
			if($this->componentArr == null){
				$this->componentArr = array();
			}
			array_push($this->componentArr, $component);
		}
		
		public function printStruct($preStr){
			echo $preStr."-".$this->name."<br>";
			if($this->componentArr != null){
				$preStr+="-";
				foreach ($this->componentArr as $key => $value) {
					$this->componentArr[$key]->printStruct($preStr);
				}
			}
		}
	}
	
	$root = new Composite("服装");
	$c1 = new Composite("男装");
	$c2 = new Composite("女装");
	
	$leaf1 = new leaf("衬衣");
	$leaf2 = new leaf("夹克");
	$leaf3 = new leaf("裙子");
	$leaf4 = new leaf("套装");
	
	$root->addChild($c1);
	$root->addChild($c2);
	
	$c1->addChild($leaf1);
	$c1->addChild($leaf2);
	$c2->addChild($leaf3);
	$c2->addChild($leaf4);
	
	$root->printStruct("-");
?>