vendor/symfony/config/Resource/SelfCheckingResourceChecker.php line 44
<?php/** This file is part of the Symfony package.** (c) Fabien Potencier <fabien@symfony.com>** For the full copyright and license information, please view the LICENSE* file that was distributed with this source code.*/namespace Symfony\Component\Config\Resource;use Symfony\Component\Config\ResourceCheckerInterface;/*** Resource checker for instances of SelfCheckingResourceInterface.** As these resources perform the actual check themselves, we can provide* this class as a standard way of validating them.** @author Matthias Pigulla <mp@webfactory.de>*/class SelfCheckingResourceChecker implements ResourceCheckerInterface{// Common shared cache, because this checker can be used in different// situations. For example, when using the full stack framework, the router// and the container have their own cache. But they may check the very same// resourcesprivate static array $cache = [];public function supports(ResourceInterface $metadata): bool{return $metadata instanceof SelfCheckingResourceInterface;}/*** @param SelfCheckingResourceInterface $resource*/public function isFresh(ResourceInterface $resource, int $timestamp): bool{$key = "$resource:$timestamp";return self::$cache[$key] ??= $resource->isFresh($timestamp);}}