/**
  * {@inheritdoc}
  */
 public function hasClient($identifier)
 {
     try {
         $result = $this->driver->contains($identifier);
     } catch (\Exception $e) {
         throw new StorageException(sprintf('Driver %s failed', get_class($this)), $e->getCode(), $e);
     }
     return $result;
 }
 /**
  * {@inheritdoc}
  */
 public function hasClient($identifier)
 {
     return $this->driver->contains($identifier);
 }