Autoloader verry simple - PHP

Autoloader.class.php

<?php
class Autoloader
{
  static function register()
  {
    spl_autoload_register(array(__CLASS__, 'autoload'));
  }
  
  static function autoload($class_name)
  {
    require 'class/' . $class_name . '.class.php';
  }
  
}

index.php

<?php

require './class/Autoloader.class.php';
Autoloader::register;