读书笔记之设计模式-观察者模式

package top.gabin.oa.web.design;

import java.util.Observable;
import java.util.Observer;

/**
 * 京东订阅者
 * @author linjiabin on  16/4/29
 */
public class JingdongObserver implements Observer {
    @Override
    public void update(Observable o, Object arg) {
        System.out.print("I‘m 京东");
        System.out.println(arg);
    }
}

package top.gabin.oa.web.design;

import java.util.Observable;
import java.util.Observer;

/**
 * 淘宝订阅者
 * @author linjiabin on  16/4/29
 */
public class TaobaoObserver implements Observer {
    @Override
    public void update(Observable o, Object arg) {
        System.out.print("I‘m 淘宝");
        System.out.println(arg);
    }
}

package top.gabin.oa.web.design;

import java.util.Observable;
import java.util.Observer;

/**
 * 快递100,物流主题
 * @author linjiabin on  16/4/29
 */
public class Kuaidi100Subject extends Observable {
    @Override
    public synchronized void addObserver(Observer o) {
        super.addObserver(o);
    }

    @Override
    public synchronized void deleteObserver(Observer o) {
        super.deleteObserver(o);
    }

    @Override
    public void notifyObservers() {
        super.notifyObservers();
    }

    @Override
    public void notifyObservers(Object arg) {
        super.notifyObservers(arg);
    }

    @Override
    public synchronized void deleteObservers() {
        super.deleteObservers();
    }

    @Override
    protected synchronized void setChanged() {
        super.setChanged();
    }

    @Override
    protected synchronized void clearChanged() {
        super.clearChanged();
    }

    @Override
    public synchronized boolean hasChanged() {
        return super.hasChanged();
    }

    @Override
    public synchronized int countObservers() {
        return super.countObservers();
    }
}

package top.gabin.oa.web.design;

import org.junit.Test;

/**
 * 测试类
 * @author linjiabin on  16/4/29
 */
public class TestObserver {

    @Test
    public void testObserver() {
        Kuaidi100Subject subject = new Kuaidi100Subject();
        TaobaoObserver taobaoObserver = new TaobaoObserver();
        subject.addObserver(taobaoObserver);
        subject.addObserver(new JingdongObserver());
        subject.setChanged();
        subject.notifyObservers("你的货已经到了");
    }

}

I‘m 京东你的货已经到了
I‘m 淘宝你的货已经到了