callback = $callback; } else { $this->callback = $this->callbackDummy; } } public function clean($mode = Zend_Cache::CLEANING_MODE_ALL, $tags = array()) {} public function remove($id) {} public function test($id) {} public function save($data, $id, $tags = array(), $specificLifetime = false) { return call_user_func($this->callback, $id, $data); } public function load($id, $doNotTestCacheValidity = false) { return call_user_func($this->callback, $id); } public function setDirectives($directives) {} protected function callbackDummy($k, $v) { return null; } } // CacherImpl class