觀察者模式類圖(截圖來自《大話設(shè)計(jì)模式》ps:以生活中的故事來分析設(shè)計(jì)模式,使人不覺得枯燥無味,很贊的一本書!):


代碼結(jié)構(gòu)圖:

Java版代碼:
import java.util.ArrayList;
public class Observer {
public static void main(String[] args) {
Subject subject= new Secretary();
AbstractObserver observer1= new StockObserver("Marry", subject);
AbstractObserver observer2= new NBAObserver("Peter", subject);
subject.attach(observer1);
subject.attach(observer2);
subject.setSbjectState("老板回來了");
subject.inform();
}
}
abstract class Subject {
private String sbjectState;
private ArrayList<AbstractObserver> observers = new ArrayList<>();
public void attach(AbstractObserver observer) {
observers.add(observer);
}
public void detach(AbstractObserver observer) {
observers.remove(observer);
}
public String getSbjectState() {
return sbjectState;
}
public void setSbjectState(String sbjectState) {
this.sbjectState = sbjectState;
}
public void inform() {
for (AbstractObserver o : observers) {
o.update();
}
}
}
class Boss extends Subject {
}
class Secretary extends Subject {
}
abstract class AbstractObserver {
private String name;
private Subject sub;
public AbstractObserver(String name, Subject sub) {
this.setName(name);
this.setSub(sub);
}
public abstract void update();
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Subject getSub() {
return sub;
}
public void setSub(Subject sub) {
this.sub = sub;
}
}
class StockObserver extends AbstractObserver {
public StockObserver(String name, Subject sub) {
super(name, sub);
}
public void update() {
System.out.println(this.getSub().getSbjectState() + this.getName()
+ "關(guān)閉股票行情,繼續(xù)工作!");
}
}
class NBAObserver extends AbstractObserver {
public NBAObserver(String name, Subject sub) {
super(name, sub);
}
@Override
public void update() {
System.out.println(this.getSub().getSbjectState() + this.getName()
+ "關(guān)閉NBA直播,繼續(xù)工作!");
}
}
分享文章:設(shè)計(jì)模式學(xué)習(xí)筆記——觀察者模式-創(chuàng)新互聯(lián)
網(wǎng)址分享:http://www.chinadenli.net/article10/djdggo.html
成都網(wǎng)站建設(shè)公司_創(chuàng)新互聯(lián),為您提供網(wǎng)頁設(shè)計(jì)公司、網(wǎng)站內(nèi)鏈、網(wǎng)站建設(shè)、企業(yè)建站、標(biāo)簽優(yōu)化、App設(shè)計(jì)
聲明:本網(wǎng)站發(fā)布的內(nèi)容(圖片、視頻和文字)以用戶投稿、用戶轉(zhuǎn)載內(nèi)容為主,如果涉及侵權(quán)請盡快告知,我們將會在第一時間刪除。文章觀點(diǎn)不代表本網(wǎng)站立場,如需處理請聯(lián)系客服。電話:028-86922220;郵箱:631063699@qq.com。內(nèi)容未經(jīng)允許不得轉(zhuǎn)載,或轉(zhuǎn)載時需注明來源: 創(chuàng)新互聯(lián)
猜你還喜歡下面的內(nèi)容