Fatal error: Uncaught exception 'InvalidArgumentException' with message 'Cannot redirect to an empty URL.' in /www/wwwroot/lichen.yunyust.cn/vendor/symfony/symfony/src/Symfony/Component/HttpFoundation/RedirectResponse.php:76 Stack trace: #0 /www/wwwroot/lichen.yunyust.cn/vendor/symfony/symfony/src/Symfony/Component/HttpFoundation/RedirectResponse.php(39): Symfony\Component\HttpFoundation\RedirectResponse->setTargetUrl(NULL) #1 /www/wwwroot/lichen.yunyust.cn/src/AppBundle/Listener/ExceptionListener.php(49): Symfony\Component\HttpFoundation\RedirectResponse->__construct(NULL) #2 [internal function]: AppBundle\Listener\ExceptionListener->onKernelException(Object(Symfony\Component\HttpKernel\Event\GetResponseForExceptionEvent), 'kernel.exceptio...', Object(Symfony\Component\HttpKernel\Debug\TraceableEventDispatcher)) #3 /www/wwwroot/lichen.yunyust.cn/vendor/symfony/symfony/src/Symfony/Component/EventDispatcher/Debug/WrappedListener.php(61): call_user_func(Array, Object(Symfony\Component\HttpKernel\Event\GetResponseForExceptio in /www/wwwroot/lichen.yunyust.cn/vendor/symfony/symfony/src/Symfony/Component/HttpFoundation/RedirectResponse.php on line 76