c++设计模式—桥接模式讲解以HuntBird游戏为例

原创

晨星成焰

修改于 2024-04-02 18:35:48

2461

修改于 2024-04-02 18:35:48

桥接模式简介

桥接模式（Bridge Pattern）是一种结构型设计模式，它用于将抽象部分和具体实现部分分离，使他们可以独立变化。这种设计模式的主要目的是把抽象化与实现化解耦，使得二者可以独立变化。桥接模式优先通过组合方式来实现两个类的联系，而不是继承4

以简单的HuntBird游戏为例介绍桥接模式

在HuntBird游戏中，需要模拟不同鸟的多种行为，鸟类中提供了对其各种行为信息进行显示的show()方法，目前游戏需要呈现的是鸽子和企鹅、老鹰的飞和游泳行为，现使用桥接模式设计该游戏

首先用startuml画一个简单的类图

再根据类图实现代码

#include <iostream>
using namespace std;

// 飞行接口
class FlyBehavior {
public:
    virtual void fly() = 0;
};

// 游泳接口
class SwimBehavior {
public:
    virtual void swim() = 0;
};

class Canfly :public FlyBehavior {
public:
    void fly() override {
        cout << "能飞" << endl;
    }
};

class Notfly :public FlyBehavior {
public:
    void fly() override {
        cout << "不能飞" << endl;
    }
};

class Canswim :public SwimBehavior {
public:
    void swim()override {
        cout << "能游泳" << endl;
    }
};

class Notswim :public SwimBehavior {
public:
    void swim()override {
        cout << "不能游泳" << endl;
    }
};

// 鸟类
class Bird {
protected:
    FlyBehavior* flyBehavior;
    SwimBehavior* swimBehavior;
public:
    Bird(FlyBehavior* fb, SwimBehavior* sb) : flyBehavior(fb), swimBehavior(sb) {}
    virtual void show() = 0;
};

// 鸽子类
class Dove : public Bird {
public:
    Dove(FlyBehavior* fb, SwimBehavior* sb) : Bird(fb, sb) {}
    void show() override {
        flyBehavior->fly();
        swimBehavior->swim();
    }
};

// 企鹅类
class Penguin : public Bird {
public:
    Penguin(FlyBehavior* fb, SwimBehavior* sb) : Bird(fb, sb) {}
    void show() override {
        flyBehavior->fly();
        swimBehavior->swim();
    }
};

//老鹰类
class Laoyin : public Bird {
public:
    Laoyin(FlyBehavior* fb, SwimBehavior* sb) : Bird(fb, sb) {}
    void show() override {
        flyBehavior->fly();
        swimBehavior->swim();
    }
};

int main() {
    int k = 0;
    while (1) {
        cout << "请输入你要测试的鸟儿：1代表鸽子，2代表老鹰，3代表企鹅" << endl;
        cin >> k;
        if (k == 1) {
            // 创建鸽子的飞行和游泳行为
            FlyBehavior* doveFly = new Canfly();
            SwimBehavior* doveSwim = new Notswim();

            // 创建鸽子
            Bird* dove = new Dove(doveFly, doveSwim);
            dove->show();

            // 删除创建的对象
            delete dove;
            delete doveFly;
            delete doveSwim;
        }
        else if (k == 2) {
            // 创建老鹰的飞行和游泳行为
            FlyBehavior* laoyinFly = new Canfly();
            SwimBehavior* laoyinSwim = new Notswim();

            // 创建老鹰
            Bird* laoyin = new Penguin(laoyinFly, laoyinSwim);
            laoyin->show();

            // 删除创建的对象
            delete laoyin;
            delete laoyinFly;
            delete laoyinSwim;
        }
        else if (k==3) {
            // 创建企鹅的飞行和游泳行为
            FlyBehavior* penguinFly = new Notfly();
            SwimBehavior* penguinSwim = new Canswim();

            // 创建企鹅
            Bird* penguin = new Penguin(penguinFly, penguinSwim);
            penguin->show();

            // 删除创建的对象
            delete penguin;
            delete penguinFly;
            delete penguinSwim;
        }
    }
    return 0;
}