Java桥接模式升级版

淩亂°似流年 2021-09-29 03:30 250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:  卡普齐诺咖啡");
        }
    
        public void getDessert() {
            System.out.println("餐后甜点:   冰淇淋");
        }
    
        public void getSorbet() {
        }
    
        public void getSandwich() {
        }
    }
    
    class Snack extends Meal {
        Snack() {
            super();
        }
    
        Snack( String type ) {
            super(type);
        }
    
        public void getSnack() {    //甜点
            imp.getAppetizer();
        }
    }
    
    class Lunch extends Meal {
        Lunch() {
            super();
        }
    
        Lunch( String type ) {
            super(type);
        }
    
        public void getLunch() {   //午餐
            imp.getSandwich();     //三明治
            imp.getBeverage();     //饮品
        }
    }
    
    class FiveCourseMeal extends Meal {
        FiveCourseMeal() {
            super();
        }
    
        FiveCourseMeal( String type ) {
            super(type);
        }
    
        public void getEnormousDinner() {   //大餐
            imp.getAppetizer();   //开胃菜
            imp.getSorbet();      //果汁冰水
            imp.getSoup();        //汤
            imp.getSorbet();      //果汁冰水
            imp.getSalad();       //沙拉
            imp.getSorbet();      //果汁冰水
            imp.getFish();        //鱼
            imp.getSorbet();      //果汁冰水
            imp.getMeat();        //肉
            imp.getDessert();     //果汁冰水
            imp.getBeverage();    //酒水
        }
    }
    
    public class CustomerBridgeDemo2 {
        private FiveCourseMeal bigMeal;
    
        public CustomerBridgeDemo2( FiveCourseMeal meal ) {
            this.bigMeal = meal;
        }
    
        public void eat() {
            bigMeal.getEnormousDinner();
            bigMeal.getDessert(); //单点一个甜点，老菜谱依然有效
        }
    
        public static void main( String[] args ) {
            FiveCourseMeal aMeal = null;
            if (args.length == 0) {
                aMeal = new FiveCourseMeal();
            } 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 FiveCourseMeal(args[0]);
                }
            } else {
                System.err.println("输入参数有误！");
                System.err.println("正确用法: java Customer [American|Italian]");
                System.exit(1);
            }
            CustomerBridgeDemo2 cus = new CustomerBridgeDemo2(aMeal);
            cus.eat();
        }
    }

**二 运行**

开胃菜    : 烤干酪
    肉食        :牛排
    餐后甜点:苹果派
    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][]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2NoZW5ncWl1bWluZw_size_16_color_FFFFFF_t_70]: /images/20210724/8d8050219a434a2080c52bc9994e51c2.png