public static function createPool()
    {
        if (Krexx::$pool !== null) {
            // The pool is there, do nothing.
            return;
        }

        $rewrite = SettingsGetter::getRewriteList();

        // Create a new pool where we store all our classes.
        // We also need to check if we have an overwrite for the pool.
        if (empty($rewrite['Brainworxx\\Krexx\\Service\\Factory\\Pool']) === true) {
            Krexx::$pool = new Pool();
        } else {
            $classname = $rewrite['Brainworxx\\Krexx\\Service\\Factory\\Pool'];
            Krexx::$pool = new $classname();
        }
        Krexx::$pool->rewrite = $rewrite;
    }