private function getDriver(): \BearFramework\App\ICacheDriver
    {
        if ($this->driver !== null) {
            return $this->driver;
        }
        throw new \Exception('No cache driver specified! Use useAppDataDriver() or setDriver() to specify one.');
    }
private function getDriver(): \BearFramework\App\ICacheDriver
    {
        if ($this->driver !== null) {
            return $this->driver;
        }
        throw new \Exception('No cache driver specified! Use useAppDataDriver() or setDriver() to specify one.');
    }
private function getDriver ( ) : \ BearFramework \ App \ ICacheDriver { if ( $ this -> driver !== null ) { return $ this -> driver ; } throw new \ Exception ( 'No cache driver specified! Use useAppDataDriver() or setDriver() to specify one.' ) ; }
Returns the cache driver.

@return \BearFramework\App\ICacheDriver
@throws \Exception
Returns the cache driver .