--- /dev/null
+<?php
+/*
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * This software consists of voluntary contributions made by many individuals
+ * and is licensed under the MIT license. For more information, see
+ * <http://www.doctrine-project.org>.
+ */
+
+namespace Doctrine\Common\Cache;
+
+/**
+ * Interface for cache drivers.
+ *
+ * @link www.doctrine-project.org
+ * @since 2.0
+ * @author Benjamin Eberlei <kontakt@beberlei.de>
+ * @author Guilherme Blanco <guilhermeblanco@hotmail.com>
+ * @author Jonathan Wage <jonwage@gmail.com>
+ * @author Roman Borschel <roman@code-factory.org>
+ * @author Fabio B. Silva <fabio.bat.silva@gmail.com>
+ * @author Kévin Dunglas <dunglas@gmail.com>
+ */
+interface Cache
+{
+ const STATS_HITS = 'hits';
+ const STATS_MISSES = 'misses';
+ const STATS_UPTIME = 'uptime';
+ const STATS_MEMORY_USAGE = 'memory_usage';
+ const STATS_MEMORY_AVAILABLE = 'memory_available';
+ /**
+ * Only for backward compatibility (may be removed in next major release)
+ *
+ * @deprecated
+ */
+ const STATS_MEMORY_AVAILIABLE = 'memory_available';
+
+ /**
+ * Fetches an entry from the cache.
+ *
+ * @param string $id The id of the cache entry to fetch.
+ *
+ * @return mixed The cached data or FALSE, if no cache entry exists for the given id.
+ */
+ public function fetch($id);
+
+ /**
+ * Tests if an entry exists in the cache.
+ *
+ * @param string $id The cache id of the entry to check for.
+ *
+ * @return bool TRUE if a cache entry exists for the given cache id, FALSE otherwise.
+ */
+ public function contains($id);
+
+ /**
+ * Puts data into the cache.
+ *
+ * If a cache entry with the given id already exists, its data will be replaced.
+ *
+ * @param string $id The cache id.
+ * @param mixed $data The cache entry/data.
+ * @param int $lifeTime The lifetime in number of seconds for this cache entry.
+ * If zero (the default), the entry never expires (although it may be deleted from the cache
+ * to make place for other entries).
+ *
+ * @return bool TRUE if the entry was successfully stored in the cache, FALSE otherwise.
+ */
+ public function save($id, $data, $lifeTime = 0);
+
+ /**
+ * Deletes a cache entry.
+ *
+ * @param string $id The cache id.
+ *
+ * @return bool TRUE if the cache entry was successfully deleted, FALSE otherwise.
+ * Deleting a non-existing entry is considered successful.
+ */
+ public function delete($id);
+
+ /**
+ * Retrieves cached information from the data store.
+ *
+ * The server's statistics array has the following values:
+ *
+ * - <b>hits</b>
+ * Number of keys that have been requested and found present.
+ *
+ * - <b>misses</b>
+ * Number of items that have been requested and not found.
+ *
+ * - <b>uptime</b>
+ * Time that the server is running.
+ *
+ * - <b>memory_usage</b>
+ * Memory used by this server to store items.
+ *
+ * - <b>memory_available</b>
+ * Memory allowed to use for storage.
+ *
+ * @since 2.2
+ *
+ * @return array|null An associative array with server's statistics if available, NULL otherwise.
+ */
+ public function getStats();
+}