/**
 * A concrete observer
 * This concrete observer can change subject through call
 * a concrete subject setState function
 */
import java.io.*;
import java.util.*;
 
public class ObserverA implements Observer {
 private Vector strVector;
 private Subject sub;
 public ObserverA(Subject s) {
 sub = s;
 //strVector = new Vector();
 }
 public void update(Subject subject) {
 strVector = subject.getState();
 System.out.println("----- ObserverA will be updated -----");
 for(int i = 0; i < strVector.size(); i++) {
 System.out.println("Num " + i + " is :" + (String)strVector.get(i));
 }
 }
 public void change(String action, String str) {
 sub.setState(action, str);
 //we can auto update
 //sub.sendNotify();
 }
 public void notifySub() {
 sub.sendNotify();
 }
}