/**
  * Write Activity Log
  *
  * @param ProjectObject $object
  * @param User $user
  * @param string $action
  * @param string $comment
  * @return null
  */
 function write($object, $user, $action, $comment = null)
 {
     if (!instance_of($user, 'User') && !instance_of($user, 'AnonymousUser')) {
         $user =& get_logged_user();
         if (!instance_of($user, 'User')) {
             return false;
         }
         // if
     }
     // if
     $activity_log = new ActivityLog();
     $activity_log->setAttributes(array('object_id' => $object->getId(), 'project_id' => $object->getProjectId(), 'action' => $action, 'comment' => $comment));
     $activity_log->setCreatedBy($user);
     return $activity_log->save();
 }