    public function dispatch($eventName, Event $event = null)
    {
        if (null === $event) {
            $event = new Event();
        }

        if (null !== $this->logger && $event->isPropagationStopped()) {
            $this->logger->debug(sprintf('The "%s" event is already stopped. No listeners have been called.', $eventName));
        }

        $this->preProcess($eventName);
        $this->preDispatch($eventName, $event);

        $e = $this->stopwatch->start($eventName, 'section');

        $this->dispatcher->dispatch($eventName, $event);

        if ($e->isStarted()) {
            $e->stop();
        }

        $this->postDispatch($eventName, $event);
        $this->postProcess($eventName);

        return $event;
    }
The software constructs all or part of an SQL command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended SQL command when it is sent to a downstream component.