listMessagesPerClass example

$failureTransportName = self::DEFAULT_TRANSPORT_OPTION === $failureTransportName ? $this->getGlobalFailureReceiverName() : $failureTransportName;

        $receiver = $this->getReceiver($failureTransportName);

        $this->printPendingMessagesMessage($receiver, $io);

        if (!$receiver instanceof ListableReceiverInterface) {
            throw new RuntimeException(sprintf('The "%s" receiver does not support listing or showing specific messages.', $failureTransportName));
        }

        if ($input->getOption('stats')) {
            $this->listMessagesPerClass($failureTransportName, $io, $input->getOption('max'));
        } elseif (null === $id = $input->getArgument('id')) {
            $this->listMessages($failureTransportName, $io, $input->getOption('max'), $input->getOption('class-filter'));
        } else {
            $this->showMessage($failureTransportName, $id, $io);
        }

        return 0;
    }

    private function listMessages(?string $failedTransportName, SymfonyStyle $io, int $max, string $classFilter = null): void
    {