private function getIdPath(string $id):string
    {
        if (!preg_match("/^[a-z0-9]$/ui", $id)) {
            throw new HandlerException(
                sprintf("The session id %s is invalid", $id),
                $this
            );
        }
        return $this->savePath."/$id.session";
    }
private function getIdPath(string $id):string
    {
        if (!preg_match("/^[a-z0-9]$/ui", $id)) {
            throw new HandlerException(
                sprintf("The session id %s is invalid", $id),
                $this
            );
        }
        return $this->savePath."/$id.session";
    }
Returns the local file path for a given id.

@param string $id
@return string
@throws HandlerException