Symfony\Component\HttpKernel\Event\FilterControllerEvent::setController PHP Method

    public function setController($controller)
    {
        // controller must be a callable
        if (!is_callable($controller)) {
            throw new \LogicException(sprintf('The controller must be a callable (%s given).', $this->varToString($controller)));
        }

        $this->controller = $controller;
    }

 public function onKernelController(FilterControllerEvent $event)
 {
     $request = $event->getRequest();
     if ('HealthCareAbroad\\SearchBundle\\Controller\\FrontendController::searchProcessAction' != $request->attributes->get('_controller')) {
         return;
     }
     $controllerAndAction = $event->getController();
     $controller = $controllerAndAction[0];
     $requestParams = $request->request->all();
     if (isset($requestParams['searchParameter']) && !empty($requestParams['searchParameter'])) {
         $event->setController(array($controller, 'searchProcessNarrowAction'));
         return;
     }
     $treatmentId = $request->get('treatment_id');
     $destinationId = $request->get('destination_id') == '0-0' ? 0 : $request->get('destination_id');
     $treatmentName = $request->get('sb_treatment');
     $destinationName = $request->get('sb_destination');
     //TODO: this will break if we are going to force the destination field in our search forms to always submit the ID
     if (!$treatmentId && !$destinationId || !$treatmentId && $treatmentName || !$destinationId && $destinationName) {
         $context = '';
         if ($treatmentName && $destinationName) {
             $context = 'combined';
         } elseif ($treatmentName) {
             $context = 'treatment';
         } elseif ($destinationName) {
             $context = 'destination';
         }
         $request->attributes->set('context', $context);
         $event->setController(array($controller, 'searchProcessKeywordsAction'));
         return;
     }
 }