protected function _get($key)
    {
        try {
            return $this->_getData($key);
        } catch (NotFoundExceptionInterface $e) {
            throw $this->_createNotFoundException($this->__('Key "%1$s" not found', array($key)), null, $e, $this, $key);
        } catch (RootException $e) {
            throw $this->_createContainerException($this->__('Could not retrieve value for key "%1$s"', array($key)), null, $e, $this);
        }
    }