add null driver

Author: macintoshplus

lib/Mactronique/PhpCache/Driver/NullDriver.php

@@ -0,0 +1,67 @@
+<?php
+
+namespace Mactronique\PhpCache\Driver;
+
+use Mactronique\PhpCache\Exception\DriverRequirementFailException;
+
+class NullDriver implements Driver
+{
+    const NAME = 'null';
+
+    public function checkDriver()
+    {
+    }
+
+    /**
+     * @return string Driver name
+     */
+    public function getName()
+    {
+        return self::NAME;
+    }
+
+    /**
+     * @param string $key
+     * @return mixed
+     */
+    public function get($key)
+    {
+        return null;
+    }
+
+    /**
+     * @param string $key
+     * @param mixed $value
+     * @param integer $ttl
+     * @return mixed
+     */
+    public function set($key, $value, $ttl = null)
+    {
+        return true;
+    }
+
+    /**
+     * @param string $key
+     * @return boolean
+     */
+    public function exists($key)
+    {
+        return false;
+    }
+
+    /**
+     * @param string $key
+     */
+    public function remove($key)
+    {
+        return true;
+    }
+
+    /**
+     * Remove all keys and value from cache
+     */
+    public function clean()
+    {
+        return true;
+    }
+}