【opencart3源码分析】路由类route.php

<?php
/**
 * @package		OpenCart
 * @author		Daniel Kerr
 * @copyright	Copyright (c) 2005 - 2017, OpenCart, Ltd. (https://www.opencart.com/)
 * @license		https://opensource.org/licenses/GPL-3.0
 * @link		https://www.opencart.com
*/

/**
* 路由类
*/
final class Router {
    // 注册路由类实例
	private $registry;
	// 前置方法
	private $pre_action = array();
	// 错误
	private $error;
	
	/**
	 * 构造方法
	 *
	 * @param	object	$route
 	*/
	public function __construct($registry) {
		$this->registry = $registry;
	}
	
	/**
	 * 
	 * 添加前置方法
	 * @param	object	$pre_action
 	*/	
	public function addPreAction(Action $pre_action) {
		$this->pre_action[] = $pre_action;
	}

	/**
	 * 
	 * 解析
	 * @param	object	$action
	 * @param	object	$error
 	*/		
	public function dispatch(Action $action, Action $error) {
		$this->error = $error;
        // 遍历前置方法
		foreach ($this->pre_action as $pre_action) {
			$result = $this->execute($pre_action);

			if ($result instanceof Action) {
				$action = $result;

				break;
			}
		}

		while ($action instanceof Action) {
			$action = $this->execute($action);
		}
	}
	
	/**
	 * 
	 *
	 * @param	object	$action
	 * @return	object
 	*/
	private function execute(Action $action) {
		$result = $action->execute($this->registry);

        // 判断是否是操作类的实例
		if ($result instanceof Action) {
			return $result;
		} 
		// 判断是否是异常类的实例
		if ($result instanceof Exception) {
			$action = $this->error;
			
			$this->error = null;
			
			return $action;
		}
	}
}