function asActivity()
{
$member = $this->getMember();
+
+ if (!$member) {
+ throw new Exception("No such member: " . $this->profile_id);
+ }
+
$group = $this->getGroup();
+ if (!$group) {
+ throw new Exception("No such group: " . $this->group_id);
+ }
+
$act = new Activity();
$act->id = $this->getURI();