Java模板模式

模板类

package com.ietree.designpattern.template;

/**
 * 模板类
 *
 * @author Root
 */
public abstract class Shopping {

    // 模板方法
    public void buyGoods() {
        userLogin();
        buy();
        pay();
    }

    // 子类不能重写的方法
    public final void userLogin() {
        System.out.println("用户登录");
    }

    // 子类必须实现的方法
    public abstract void buy();

    // 钩子方法
    public void pay() {
        System.out.println("使用银联卡支付");
    }
}

实现类：

package com.ietree.designpattern.template;

public class ShoesShopping extends Shopping {

    @Override
    public void buy() {
        System.out.println("购买鞋子");
    }

    @Override
    public void pay() {
        System.out.println("使用支付宝支付");
    }

}

package com.ietree.designpattern.template;

public class ClothesShopping extends Shopping {

    @Override
    public void buy() {
        System.out.println("购买西装");
    }

}

测试类：

package com.ietree.designpattern.template.test;

import com.ietree.designpattern.template.ClothesShopping;
import com.ietree.designpattern.template.ShoesShopping;
import com.ietree.designpattern.template.Shopping;

public class MyTest {
    public static void main(String[] args) {
        Shopping shoesShopping = new ShoesShopping();
        shoesShopping.buyGoods();
        System.out.println("-------------------");
        Shopping clothesShopping = new ClothesShopping();
        clothesShopping.buyGoods();
    }
}

程序输出结果：

用户登录
购买鞋子
使用支付宝支付
-------------------
用户登录
购买西装
使用银联卡支付