private function validateRedirections()
    {
        foreach ($this->redirections as $redirection)
        {
            if(!(
                array_key_exists('source', $redirection)
                &&
                array_key_exists('target', $redirection)
                &&
                array_key_exists('type', $redirection)
            ))
            {
                throw new ConfigurationException("Invalid redirection line: " . implode(',', $redirection) . ".");
            }
        }
    }