策略模式Strategy

abstract class Customer{
    int money;
    public abstract void payFor();
}
class BOSS extends Customer{
    public void payFor(){
        System.out.println("工作态度不错");
    }
}
class manager extends Customer{
    public void payFor(){
        money = money - 10;
    }
}
class SuperMarket {
    public void pay(Customer customer){ customer.payFor();}
}