PHP一个类AOP的实现

1.Wrapper.class.php

<?php

/**
 * 包装器(Wrapper).
 * Wrapper是一个AOP_LIKE的实现. 也可以看作监听者模式的实现.
 * 一个Wrapper报装了一个对象(source). source可以是任意对象(不包括数组及原子类型),甚至是一个Wrapper.
 *
 * 包装器可以任意添加饰品(Decoration).通过Wrapper调用source的函数的流程将是:
 *	unpacking --> teardown --> open --> setup --> packing.
 *
 *	例如调用source->doXX(),各个流程将是:
 *	unpacking: 	解包. 这是调用任意source的函数都会调用的方法;
 *	teardown: 	撕掉饰品. 对于Wrapper中的每个Decoration,调用其before()函数;
 *	open: 		真正调用source->doXX()函数;
 *	setup: 		重新贴上饰品. 对于Wrapper中的每个Decoration,调用其after()函数;
 *	packing:	重新打包.  这是调用任意source的函数都会调用的方法;
 *
 */
class Wrapper{
	private $source;

	/**
	 * @var bool
	 */
	private $undecorated;

	/**
	 * @var array[Decoration]
	 */
	private $decorations=array();

	public function __construct($source){
		$this->source = $source;
	}

	public function __call($name,$parameters){
		$this->unpacking($name,$parameters);
		$this->tearDown($name,$parameters);

		//opening
		$retval = $this->opening($name,$parameters);

		$this->setup($retval,$name,$parameters);
		$this->packing($retval,$name,$parameters);

		return $retval;
	}

	public function unpacking($name,$parameters){
	}

	public function packing($name,$parameters){
	}
	
	private function opening($name,$parameters){
		// opening
		if(method_exists($this->source, $name)){
			$retval = call_user_func_array(array($this->source,$name),$parameters);
		}
		
		return $retval;
	}

	public function tearDown($name,$parameters){
		if($this->undecorated){
			return;
		}
		$before='before';
		foreach ($this->decorations as $d){
			if(method_exists($d, $before))
			{ 
				$d->$before($name,$parameters);
			} 
		}
	}

	public function setup($retval,$name,$parameters){
		if($this->undecorated){
			return ;
		}
		$after='after';
		foreach ($this->decorations as $d){
			if(method_exists($d, $after))
			{ 
				$d->$after($retval,$name,$parameters);
			} 
		}
	}

	public function decarate($decoration){
		$this->decorations[] = $decoration;
	}



	public static function wrap($source){
		//  wrap the source
		$wrapperConfig = Aop::app()->wrappers[get_class($source)];
		if($wrapperConfig){
			$wrapperClass = $wrapperConfig['class'];
			$wrapper = new $wrapperClass($source);

			foreach ($wrapperConfig['decorations'] as $item){
				if(class_exists($item)){
					$decoration = new $item;
					$wrapper->decarate($decoration);
				}
			}
		}
		return $wrapper?$wrapper:$source;
	}

}

?>
           

2. test.php 

<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />

<?php

require 'Wrapper.class.php';

//该类和Wrapper类联合使用，用来获取配置文件

class Aop{

//var wrappers=array();

function __construct(){

   //配置文件

$this->wrappers=array(

'ContentService'=>array(

'class'=>'ContentWrapper',

'decorations'=>array(

'DasaiContentDecoration',

)

),

'AOPWorker'=>array(//for test

'class'=>'DiagnosisWrapper',

'decorations'=>array(

'DasaiDiagnosisDecoration'

),

),

);

}

public static function app(){

return new Aop();

}

}

class AOPWorker{

public function testAOP(){

echo '<br>这里是调用的地方 <br>';

return 'OK';

}

}

class DiagnosisWrapper extends Wrapper{

public function unpacking($name, $parameters){

echo "DiagnosisWrapper:喂,有人调用$name,我要解包了.<br>";

}

public function packing($retval,$name, $parameters){

echo "DiagnosisWrapper:喂,调用$name,结果为$retval,重新打包好了.<br>";

}

}

class DasaiDiagnosisDecoration  {

public function before($name,$parameters){

echo "DasaiDiagnosisDecoration:开始调用$name , 信息 ：$parameters[0] 已经告诉张三李四了.<br>";

}

public function after($retval,$name,$parameters){

echo "<br>DasaiDiagnosisDecoration:结束调用$name,告诉霍金和Sheldon了.<br>";

}

}

function testAOP(){// test aop  测试入口

$aop = Wrapper::wrap(new AOPWorker());

$aop->testAOP(33347);

}

testAOP();

?>