东南大学Java设计模式作业观察者模式(2)

p=new JPanel(); this.getContentPane().add(p); lb=new LoginBean(); lb.addLoginEventListener(this); } public void validateLogin(LoginEvent event) { String userName=event.getUserName(); String password=event.getPassword(); } }

实例三 老师、学生、PPT

代码：

import java.util.*;

public abstract class MySubject {

protected ArrayList observers = new ArrayList(); public abstract void attach(MyObserver obs); public abstract void detach(MyObserver obs); public abstract void cry(); }

public class PPT extends MySubject {

public void attach(MyObserver obs) { obs.add(obs); }

public void detach(MyObserver obs) { obs.remove(obs); }

public void look() { for(Object obs:obs) { ((MyObserver)obs).response(); } } }

public interface MyObserver {

public void response(); }

public class Teacher {

public void response() { //具体更新代码 } }

public class Student {

public void response() { //具体更新代码 } }