Request::wantsJson PHP Method

        public static function wantsJson()
        {
            return \Illuminate\Http\Request::wantsJson();
        }

 /**
  * Start the creation of a new balance payment
  *   Details get posted into this method
  * @param $userId
  * @throws \BB\Exceptions\AuthenticationException
  * @throws \BB\Exceptions\FormValidationException
  * @throws \BB\Exceptions\NotImplementedException
  */
 public function store($userId)
 {
     $user = User::findWithPermission($userId);
     $this->bbCredit->setUserId($user->id);
     $requestData = \Request::only(['reason', 'amount', 'return_path', 'ref']);
     $amount = $requestData['amount'] * 1 / 100;
     $reason = $requestData['reason'];
     $returnPath = $requestData['return_path'];
     $ref = $requestData['ref'];
     //Can the users balance go below 0
     $minimumBalance = $this->bbCredit->acceptableNegativeBalance($reason);
     //What is the users balance
     $userBalance = $this->bbCredit->getBalance();
     //With this payment will the users balance go to low?
     if ($userBalance - $amount < $minimumBalance) {
         if (\Request::wantsJson()) {
             return \Response::json(['error' => 'You don\'t have the money for this'], 400);
         }
         \Notification::error("You don't have the money for this");
         return \Redirect::to($returnPath);
     }
     //Everything looks gooc, create the payment
     $this->paymentRepository->recordPayment($reason, $userId, 'balance', '', $amount, 'paid', 0, $ref);
     //Update the users cached balance
     $this->bbCredit->recalculate();
     if (\Request::wantsJson()) {
         return \Response::json(['message' => 'Payment made']);
     }
     \Notification::success("Payment made");
     return \Redirect::to($returnPath);
 }