Handle language changing in CakePHP

LanguageComponent.php

<?php

App::uses('Component', 'Controller');

class LanguageComponent extends Component {

    public function initialize(Controller $controller) {

        $this->autoSelectLanguage($controller);

    }

    private function autoSelectLanguage(Controller $controller) {

        if (isset($controller->request->query['lang'])) {
            $controller->Session->write('Config.language', $controller->request->query['lang']);
        }

        if ($controller->Session->check('Config.language')) {
            Configure::write('Config.language', $controller->Session->read('Config.language'));
        }

    }

}