public static void main(String[] args) {
MySubject subject = new MySubject();
Observer observer1 = new Subscriber("Observer 1");
Observer observer2 = new Subscriber("Observer 2");
Observer observer3 = new Subscriber("Observer 3");
subject.register(observer1);
subject.register(observer2);
subject.register(observer3);
observer1.setSubject(subject);
observer2.setSubject(subject);
observer3.setSubject(subject);
observer1.update();
subject.postMessage("New Message");
}
