108      * @param VCalendar $existingObject
112     public function processMessage(Message $itipMessage, VCalendar $existingObject = null)  argument
121                 return $this->processMessageRequest($itipMessage, $existingObject);
124                 return $this->processMessageCancel($itipMessage, $existingObject);
127                 return $this->processMessageReply($itipMessage, $existingObject);
134         return $existingObject;
268      * @param VCalendar $existingObject
272     protected function processMessageRequest(Message $itipMessage, VCalendar $existingObject = null)  argument
274         if (!$existingObject) {
277             $existingObject = new VCalendar();
279                 $existingObject->add(clone $component);
285             foreach ($existingObject->getComponents() as $component) {
286                 $existingObject->remove($component);
289                 $existingObject->add(clone $component);
293         return $existingObject;
304      * @param VCalendar $existingObject
308     protected function processMessageCancel(Message $itipMessage, VCalendar $existingObject = null)  argument
310         if (!$existingObject) {
314             foreach ($existingObject->VEVENT as $vevent) {
320         return $existingObject;
330      * @param VCalendar $existingObject
334     protected function processMessageReply(Message $itipMessage, VCalendar $existingObject = null)  argument
338         if (!$existingObject) {
358         foreach ($existingObject->VEVENT as $vevent) {
399             $recurrenceIterator = new EventIterator($existingObject, $itipMessage->uid);
441             $existingObject->add($newObject);
444         return $existingObject;