Aquí lo llevas...
Código PHP:
<?php
/**
* Singleton class
*/
class Singleton {
/**
* The instance of this class
* @var object
*/
private static $instance = null;
/**
* Returns only one instance of this class
* @return object
*/
public static function instance() {
if (!self::$instance instanceof self)
self::$instance = new self();
return self::$instance;
}
/**
* Private constructor
*/
private function __construct() {
}
/**
* No serialization allowed
*/
public function __sleep() {
trigger_error("No serialization allowed!", E_USER_ERROR);
}
/**
* No cloning allowed
*/
public function __clone() {
trigger_error("No cloning allowed!", E_USER_ERROR);
}
}