Simple producer-consumer pattern implementation

event.php

<?php

/**
 * events.php
 * Простая реализация паттерна producer-consumer (Listener)
 *
 * Author: swvitaliy
 */
class Listener {
	
	private $func = null;
	private $lastResult = null;

	public function __construct ($func)
	{
		$this->func = $func ? new ReflectionFunction($func) : null;
	}

	public function getLastResult () 
	{
		return $this->lastResult;
	}

	public function __invoke ()
	{
		return $this->lastResult = $this->func ? 
				$this->func->invokeArgs(func_get_args()) : null;
	}

}

class Producer {

	protected $listeners = array (
			// 'callable_method' => object Listener
		);

	public function callListeners ($event)
	{
		$args = func_get_args();
		array_shift($args);
		foreach ($this->listeners[$event] as $v)
			call_user_func_array($v, $args);
	}

	public function addListener ($event, $action)
	{
		if (!isset($this->listeners [$event]))
			$this->listeners [$event] = array();
		$this->listeners [$event][] = new Listener($action);
	}

	public function addListeners ($event, $actions) 
	{
		foreach ($actions as $action)
			$this->addListener($event, $action);
	}

	public function clearListeners ()
	{
		if (isset($this->listeners [$event]))
			$this->listeners [$event] = array();
		
		
	}

	public function getListeners ($event, $default = FALSE)
	{
		return isset($this->listeners [$event]) ? 
				$this->listeners [$event] : $default;

	}

}

/*
class Obj {

	public function getProducer ()
	{
		return empty($this->producer) 
				? $this->producer = new Producer : $this->producer;
	}

}

class O1 extends Obj {
	
	public function a() {
		echo "call O1::a\n";
		$this->getProducer()->callListeners('a');
	}

}

$o1 = new O1;
$o1->getProducer()->addListener('a', 
		function () { 
			echo "call Listener \n"; 
		});
$o1->a();
*/