觀察者設計模式 （observer模式） java實現

package Observer.MyTest;import java.util.Observable;import    java.util.Observer; public class ObserverTest {/** * @param args */public static void main(String[] args) {observered oe=new observered();observerB ob=new observerB();oe.addObserver(new observerA());oe.addObserver(ob);oe.showb();//oe.showg();}//被觀察者static class observered extends  Observable{//場上表現public void showg(){System.out.println("選手變現得不錯");setChanged();notifyObservers(1);}public void showb(){System.out.println("選手變現得一般");setChanged();notifyObservers(2);}}//觀察者--競爭者static class observerA implements Observer{@Overridepublic void update(Observable o, Object arg) {Integer i=(Integer) arg;System.out.print("競爭者");if(i.intValue()==1){System.out.println("有壓力");}else{System.out.println("有希望進入下一輪");}}}//觀察者--觀眾static class observerB implements Observer{@Overridepublic void update(Observable o, Object arg) {Integer i=(Integer) arg;System.out.print("觀眾");if(i.intValue()==1){System.out.println("鼓掌");}else{System.out.println("唏噓");}}}}