wy/ZeedFramework/library/Zeed/Registry.php

<?php
/**
 * Zeed Platform Project
 * Based on Zeed Framework & Zend Framework.
 *
 * BTS - Billing Transaction Service
 * CAS - Central Authentication Service
 *
 * LICENSE
 * http://www.zeed.com.cn/license/
 *
 * @category   Zeed
 * @package    Zeed_Registry
 * @copyright  Copyright (c) 2010 Zeed Technologies PRC Inc. (http://www.zeed.com.cn)
 * @author     Zeed Team (http://blog.zeed.com.cn)
 * @since      2010-6-30
 * @version    SVN: $Id: Registry.php 6710 2010-09-08 13:51:53Z xsharp $
 */

/**
 * 拷贝自Zend_Registry
 */
class Zeed_Registry extends ArrayObject
{
    /**
     * Class name of the singleton registry object.
     * @var string
     */
    private static $_registryClassName = 'Zeed_Registry';
    
    /**
     * Registry object provides storage for shared objects.
     * @var Zeed_Registry
     */
    private static $_registry = null;
    
    /**
     * Retrieves the default registry instance.
     *
     * @return Zeed_Registry
     */
    public static function getInstance()
    {
        if (self::$_registry === null) {
            self::init();
        }
        
        return self::$_registry;
    }
    
    /**
     * Set the default registry instance to a specified instance.
     *
     * @param Zeed_Registry $registry An object instance of type Zeed_Registry,
     *   or a subclass.
     * @return void
     * @throws Zeed_Exception if registry is already initialized.
     */
    public static function setInstance(Zeed_Registry $registry)
    {
        if (self::$_registry !== null) {
            throw new Zeed_Exception('Registry is already initialized');
        }
        
        self::setClassName(get_class($registry));
        self::$_registry = $registry;
    }
    
    /**
     * Initialize the default registry instance.
     *
     * @return void
     */
    protected static function init()
    {
        self::setInstance(new self::$_registryClassName());
    }
    
    /**
     * Set the class name to use for the default registry instance.
     * Does not affect the currently initialized instance, it only applies
     * for the next time you instantiate.
     *
     * @param string $registryClassName
     * @return void
     * @throws Zeed_Exception if the registry is initialized or if the
     *   class name is not valid.
     */
    public static function setClassName($registryClassName = 'Zeed_Registry')
    {
        if (self::$_registry !== null) {
            throw new Zeed_Exception('Registry is already initialized');
        }
        
        if (! is_string($registryClassName)) {
            throw new Zeed_Exception("Argument is not a class name");
        }
        
        /**
         * @see Zeed_Loader
         */
        if (! class_exists($registryClassName)) {
            Zeed_Loader::loadClass($registryClassName);
        }
        
        self::$_registryClassName = $registryClassName;
    }
    
    /**
     * Unset the default registry instance.
     * Primarily used in tearDown() in unit tests.
     * @returns void
     */
    public static function _unsetInstance()
    {
        self::$_registry = null;
    }
    
    /**
     * getter method, basically same as offsetGet().
     *
     * This method can be called from an object of type Zeed_Registry, or it
     * can be called statically.  In the latter case, it uses the default
     * static instance stored in the class.
     *
     * @param string $index - get the value associated with $index
     * @return mixed
     * @throws Zeed_Exception if no entry is registerd for $index.
     */
    public static function get($index)
    {
        $instance = self::getInstance();
        
        if (! $instance->offsetExists($index)) {
            throw new Zeed_Exception("No entry is registered for key '$index'");
        }
        
        return $instance->offsetGet($index);
    }
    
    /**
     * setter method, basically same as offsetSet().
     *
     * This method can be called from an object of type Zeed_Registry, or it
     * can be called statically.  In the latter case, it uses the default
     * static instance stored in the class.
     *
     * @param string $index The location in the ArrayObject in which to store
     *   the value.
     * @param mixed $value The object to store in the ArrayObject.
     * @return void
     */
    public static function set($index,$value)
    {
        $instance = self::getInstance();
        $instance->offsetSet($index, $value);
    }
    
    /**
     * Returns TRUE if the $index is a named value in the registry,
     * or FALSE if $index was not found in the registry.
     *
     * @param  string $index
     * @return boolean
     */
    public static function isRegistered($index)
    {
        if (self::$_registry === null) {
            return false;
        }
        return self::$_registry->offsetExists($index);
    }
    
    /**
     * Constructs a parent ArrayObject with default
     * ARRAY_AS_PROPS to allow acces as an object
     *
     * @param array $array data array
     * @param integer $flags ArrayObject flags
     */
    public function __construct($array = array(),$flags = parent::ARRAY_AS_PROPS)
    {
        parent::__construct($array, $flags);
    }
    
    /**
     * @param string $index
     * @returns mixed
     *
     * Workaround for http://bugs.php.net/bug.php?id=40442 (ZF-960).
     */
    public function offsetExists($index)
    {
        return array_key_exists($index, $this);
    }

}