php/external/Zend/Registry.php

<?php

/**
 * Zend Framework
 *
 * LICENSE
 *
 * This source file is subject to the new BSD license that is bundled
 * with this package in the file LICENSE.txt.
 * It is also available through the world-wide-web at this URL:
 * http://framework.zend.com/license/new-bsd
 * If you did not receive a copy of the license and are unable to
 * obtain it through the world-wide-web, please send an email
 * to license@zend.com so we can send you a copy immediately.
 *
 * @category   Zend
 * @package    Zend_Registry
 * @copyright  Copyright (c) 2005-2008 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 * @version    $Id: Registry.php 8064 2008-02-16 10:58:39Z thomas $
 */

/**
 * Generic storage class helps to manage global data.
 *
 * @category   Zend
 * @package    Zend_Registry
 * @copyright  Copyright (c) 2005-2008 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 */
class Zend_Registry extends ArrayObject {
  /**
   * Class name of the singleton registry object.
   * @var string
   */
  private static $_registryClassName = 'Zend_Registry';
  
  /**
   * Registry object provides storage for shared objects.
   * @var Zend_Registry
   */
  private static $_registry = null;

  /**
   * Retrieves the default registry instance.
   *
   * @return Zend_Registry
   */
  public static function getInstance() {
    if (self::$_registry === null) {
      self::init();
    }
    
    return self::$_registry;
  }

  /**
   * Set the default registry instance to a specified instance.
   *
   * @param Zend_Registry $registry An object instance of type Zend_Registry,
   *   or a subclass.
   * @return void
   * @throws Zend_Exception if registry is already initialized.
   */
  public static function setInstance(Zend_Registry $registry) {
    if (self::$_registry !== null) {
      require_once 'external/Zend/Exception.php';
      throw new Zend_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 $registryClassName
   * @return void
   * @throws Zend_Exception if the registry is initialized or if the
   *   class name is not valid.
   */
  public static function setClassName($registryClassName = 'Zend_Registry') {
    if (self::$_registry !== null) {
      require_once 'external/Zend/Exception.php';
      throw new Zend_Exception('Registry is already initialized');
    }
    
    if (! is_string($registryClassName)) {
      require_once 'external/Zend/Exception.php';
      throw new Zend_Exception("Argument is not a class name");
    }
    
    /**
     * @see Zend_Loader
     */
    require_once 'external/Zend/Loader.php';
    Zend_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 Zend_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 Zend_Exception if no entry is registerd for $index.
   */
  public static function get($index) {
    $instance = self::getInstance();
    
    if (! $instance->offsetExists($index)) {
      require_once 'external/Zend/Exception.php';
      throw new Zend_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 Zend_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);
  }

  /**
   * @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);
  }

}