public function __construct($a = array())
{
$this->dir = isset($a['dir']) ? APP_PATH . DS . 'cache' . DS . $a['dir'] : APP_PATH . DS . 'cache';
$this->lang = isset($a['lang']) ? $a['lang'] : Language::getCurrentLang();
$this->time = isset($a['time']) ? $a['time'] : -1;
}