public void action() {
ACLMessage message = receive(template);
if(message != null) {
try{
Done d = (Done)getContentManager().extractContent(message);
Action a = (Action)d.getAction();
AID tn = a.getActor();
StartNotify sn = (StartNotify) a.getAction();
AID observed = sn.getObserved();
notifiers.put(observed, tn);
}