/**
*
* @return Ac_Storage_Cache
*/
public static function &cache()
{
if (empty(self::$cache)) {
$cache_class = self::config("cache.class", "Ac_Storage_Cache_File");
self::$cache = new $cache_class(self::config("cache.path"));
if (!self::$cache instanceof Ac_Storage_Cache) {
self::exception("{$cache_class} is not a valid Ac_Storage_Cache instance");
}
}
return self::$cache;
}