Java桥接模式简单版

怼烎@ 2021-09-29 03:26 214阅读 0赞

**一 代码**

class Meal
    {
        protected MealImp imp;
        public Meal()
        {
            imp = new AmericanMealImp();
        }
        public Meal(String type)
        {
            if (type.equals("American"))
                imp = new AmericanMealImp();
            if (type.equals("Italian"))
                imp = new ItalianMealImp();
        }
    
        public void getFirstCourse() {
            imp.getAppetizer();
        }
    
        public void getSecondCourse() {
            imp.getMeat();
        }
    
        public void getBeverage() {
            imp.getBeverage();
        }
    
        public void getDessert() {
            imp.getDessert();
        }
    }
    
    interface MealImp {
        public abstract void getAppetizer();
        public abstract void getSoup();
        public abstract void getSalad();
        public abstract void getFish();
        public abstract void getMeat();
        public abstract void getSorbet();
        public abstract void getPasta();
        public abstract void getBeverage();
        public abstract void getDessert();
        public abstract void getSandwich();
    }
    class AmericanMealImp implements MealImp {
        public void getAppetizer()   {
            System.out.println("开胃菜    : 烤干酪"); }
        public void getSoup()        {}
        public void getSalad()       {}
        public void getFish()        {}
        public void getMeat()        {
            System.out.println("肉食        :牛排"); }
        public void getPasta()       {}
        public void getBeverage()    {
            System.out.println("酒水        :啤酒"); }
        public void getDessert()     {
            System.out.println("餐后甜点:苹果派"); }
        public void getSorbet()      {}
        public void getSandwich()    {}
    }
    class ItalianMealImp implements MealImp {
        public void getAppetizer()   {
            System.out.println("开胃菜: 意大利蔬菜拼盘"); }
        public void getSoup()        {}
        public void getSalad()       {}
        public void getFish()        {}
        public void getMeat()        {
            System.out.println("肉食:      意大利柠檬香煎鸡排"); }
        public void getPasta()       {}
        public void getCheesePlate() {}
        public void getBeverage()    {
            System.out.println("酒水:  卡布奇诺咖啡"); }
        public void getDessert()     {
            System.out.println("餐后甜点:   冰淇淋"); }
        public void getSorbet()      {}
        public void getSandwich()    {}
    }
    
    public class CustomerBridgeDemo {
    
        private Meal meal;
    
        public CustomerBridgeDemo(Meal aMeal) { meal = aMeal; }
    
        public void eat() {
            meal.getFirstCourse();
            meal.getSecondCourse();
            meal.getBeverage();
            meal.getDessert();
        }
    
        public static void main(String[] args) {
            Meal aMeal = null;
            if (args.length == 0) {
                aMeal = new Meal();
            }
            else if (args.length == 1) {
                if (!(args[0].equals("American")) && !(args[0].equals("Italian")) ) {
                    System.err.println("输入参数有误！");
                    System.err.println("正确用法: java Customer [American|Italian]");
                    System.exit(1);
                }
                else {
                    aMeal = new Meal(args[0]);
                }
            }
            else { // error
                System.err.println("输入参数有误！");
                System.err.println("正确用法: java Customer [American|Italian]");
                System.exit(1);
            }
    
            CustomerBridgeDemo cus = new CustomerBridgeDemo(aMeal);
            cus.eat();
        }
    }

**二 运行**

开胃菜    : 烤干酪
    肉食        :牛排
    酒水        :啤酒
    餐后甜点:苹果派

**三 类图**

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2NoZW5ncWl1bWluZw_size_16_color_FFFFFF_t_70][]

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