www.gusucode.com > Piwik 网站流量统计系统 v2.9.1PHP源码程序 > Piwik 网站流量统计系统 v2.9.1/piwik/piwik/core/Singleton.php
<?php /** * Piwik - free/libre analytics platform * * @link http://piwik.org * @license http://www.gnu.org/licenses/gpl-3.0.html GPL v3 or later * */ namespace Piwik; /** * The singleton base class restricts the instantiation of derived classes to one object only. * * All plugin APIs are singletons and thus extend this class. * * @api */ class Singleton { protected static $instances; protected function __construct() { } final private function __clone() { } /** * Returns the singleton instance for the derived class. If the singleton instance * has not been created, this method will create it. * * @return Singleton */ public static function getInstance() { $class = get_called_class(); if (!isset(self::$instances[$class])) { self::$instances[$class] = new $class; } return self::$instances[$class]; } /** * Used in tests only * @ignore */ public static function unsetInstance() { $class = get_called_class(); unset(self::$instances[$class]); } /** * Sets the singleton instance. For testing purposes. * @ignore */ public static function setSingletonInstance($instance) { $class = get_called_class(); self::$instances[$class] = $instance; } }