@Override
    public void update(Observable o, Object arg) {
        //System.out.println("update");
        if (o instanceof ClientConnection) {
            // Echo to all clients
            if (arg instanceof ChatMessage) {
                this.setChanged();
                this.notifyObservers(arg);
            } else if (arg instanceof ServerMessage) {
                parseRequest((ServerMessage) arg);
            } else if (arg instanceof ChatPerson) {
                people.add((ChatPerson) arg);
                this.setChanged();
                this.notifyObservers(arg);
            }
        }
    }