设计模式--策略模式

package com.offcn.designpattern.strategypattern;

public class StragegypatternDemo {
    public static void main(String[] args) {
        Stragegy s1= new OldCustomerFewStragegy();
        Context c1 = new Context(s1);
        c1.printPrice(543);
        Stragegy s2 = new NewCustomerManyStragegy();
        Context c2 = new Context(s2);
        c2.printPrice(543);
    }
}
//上下文角色，负责和具体的策略类交互
class Context{
    private Stragegy stragegy;

    public Context(Stragegy stragegy) {
        this.stragegy = stragegy;
    }
    public void printPrice(double price){
        System.out.println("您该报价"+stragegy.getPrice(price));
    }
}
//策略接口
interface Stragegy{
    public double getPrice(double price);
}
//新用户小批量购买
class NewCustomerFewStragegy implements Stragegy{

    @Override
    public double getPrice(double price) {
        System.out.println("原价购买");
        return price;
    }
}
//新用户，大批量购买
class NewCustomerManyStragegy implements Stragegy{

    @Override
    public double getPrice(double price) {
        System.out.println("95折");
        return price * 0.95;
    }
}
//老用户，小批量购买
class OldCustomerFewStragegy implements Stragegy {

    @Override
    public double getPrice(double price) {
        System.out.println("9折");
        return price * 0.90;
    }
}
    //老用户，大批量购买
class OldCustomerManyStragegy implements Stragegy{

    @Override
    public double getPrice(double price) {
        System.out.println("85折");
        return price * 0.85;
    }
}