fetch() protected method

This methods is triggered when the cache missed or a reload is required.
protected fetch ( Request $request, boolean $catch = false ) : Response
$request Symfony\Component\HttpFoundation\Request A Request instance
$catch boolean whether to process exceptions
return Symfony\Component\HttpFoundation\Response A Response instance
 /**
  * Made public to allow event subscribers to do refresh operations.
  *
  * {@inheritDoc}
  */
 public function fetch(Request $request, $catch = false)
 {
     return parent::fetch($request, $catch);
 }