AuditableBehavior::_requestId PHP Method

    protected function _requestId()
    {
        if (empty(self::$_requestId)) {
            // Class 'String' was deprecated in CakePHP 2.7 and replaced by 'CakeText' (Issue #41)
            $UuidClass = class_exists('CakeText') ? 'CakeText' : 'String';
            self::$_requestId = $UuidClass::uuid();
        }
        return self::$_requestId;
    }

 /**
  * Get request ID
  *
  * @return null|string The request ID.
  */
 protected function _requestId()
 {
     if (empty(self::$_requestId)) {
         // Class 'String' was deprecated in CakePHP 2.7 and replaced by 'CakeText' (Issue #41)
         $UuidClass = class_exists('CakeText') ? 'CakeText' : 'String';
         self::$_requestId = $UuidClass::uuid();
     }
     return self::$_requestId;
 }