工厂方法和观察者模式的一个真实案例

import java.util.ArrayList;

class Manager
{
    private String name; //经理的名字
    public Manager(String string) {
        name=string;
    }
    public void update(String id)
    {
        System.out.println("哈哈"+id+"房子已经被买了，好开心");
    }
    
    
}
//抽象房子
abstract class House
{
    private String id;
    private int price;
    private int  status=0;// status=0没有被卖掉
    private ArrayList<Manager> m=new ArrayList<Manager>();
    public void setStatus()
    {
        status=1;   //卖房子了
        for(Manager ma:m)
        {
        ma.update(id);
        }
    }
    public House(String id,int price)
    {
        this.id=id;
        this.price=price;
    }
    public  void addObserver(Manager ma)
    {
        m.add(ma);
    }
    
    
}
//具体房子
class BigHouse extends House
{
    public BigHouse(String id, int price) {
        super(id, price);
        // TODO Auto-generated constructor stub
    }

    public void method()
    {
        System.out.println("BigHouse");
        
    }
}
//具体房子
class smallHouse extends House
{
    
    public smallHouse(String id, int price) {
        super(id, price);
        // TODO Auto-generated constructor stub
    }

    public void met()
    {
        System.out.println("smallHouse");
    }
}
//工厂接口
interface factory
{
    public House getInstance(String id,int price);
    
}
//大房子工厂
class BigFactory implements factory
{

    @Override
    public House getInstance(String id, int price) {
        // TODO Auto-generated method stub
        return new BigHouse(id,price);
    }

    
}
class smallFactory implements factory
{

    @Override
    public House getInstance(String id, int price) {
        // TODO Auto-generated method stub
        return new smallHouse(id,price);
    }

    
    
}


public class 设计模式1 {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
    //创建一大房子对象
    House h1=new BigFactory().getInstance("0001", 10000000);
    //一个小房子对象
    ((BigHouse) h1).method();
    House h2=new smallFactory().getInstance("333", 100);
    Manager ma=new Manager("zhangsan");
    h2.addObserver(ma);
    h2.setStatus();
    
    
    
    
    
    //卖掉
    
    

        
    }

}

http://blog.csdn.net/lovelion/article/details/7430515