--- /dev/null
+<?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;
+
+/**
+ * Interface for Resources that can check for freshness autonomously,
+ * without special support from external services.
+ *
+ * @author Matthias Pigulla <mp@webfactory.de>
+ */
+interface SelfCheckingResourceInterface extends ResourceInterface
+{
+ /**
+ * Returns true if the resource has not been updated since the given timestamp.
+ *
+ * @param int $timestamp The last time the resource was loaded
+ *
+ * @return bool True if the resource has not been updated, false otherwise
+ */
+ public function isFresh($timestamp);
+}