代码改变世界

策略模式

2015-04-16 23:09  foolbread-老陈  阅读(145)  评论(0编辑  收藏  举报

    策略模式:定义算法族,分别封装起来,让它们之间可以互相替换,此模式让算法的变化独立于使用算法的客户。——《HEAD FIRST 设计模式》

    我的C++代码:

#ifndef DESIGN_STRATEGY_H_
#define DESIGN_STRATEGY_H_

class FlyBehavior
{
public:
    virtual void fly() = 0;
};

class QuackBehavior
{
public:
    virtual void quack() = 0;
};

class Duck
{
public:
    void Fly(){this->m_pFly->fly();}
    void Quack(){this->m_pQuack->quack();}
protected:
    FlyBehavior*    m_pFly;
    QuackBehavior* m_pQuack;
};
///////////////////////////////////////

class FlyWithWings: public FlyBehavior
{
public:
    virtual void fly();
};

class FlyNoWay: public FlyBehavior
{
public:
    virtual void fly();
};

class TrueQuack: public QuackBehavior
{
public:
    virtual void quack();
};

class Squeak: public QuackBehavior
{
public:
    virtual void quack();
};

class MuteQuack: public QuackBehavior
{
public:
    virtual void quack();
};
///////////////////////////////////////

class MallardDuck: public Duck
{
public:
    MallardDuck();
};

class RedHeadDuck: public Duck
{
public:
    RedHeadDuck();
};

class RubberDuck: public Duck
{
public:
    RubberDuck();
};

class DecoyDuck: public Duck
{
public:
    DecoyDuck();
};
#endif // DESIGN_STRATEGY_H_
#include "strategy.h"
#include <iostream>

void FlyWithWings::fly()
{
   std::cout << "fly with wings!" << std::endl;
}

void FlyNoWay::fly()
{
    std::cout << "fly no way!" << std::endl;
}

void TrueQuack::quack()
{
    std::cout << "Quack!" << std::endl;
}

void Squeak::quack()
{
    std::cout << "Squeak!" << std::endl;
}

void MuteQuack::quack()
{
    std::cout << "Mute quack!" << std::endl;
}

MallardDuck::MallardDuck()
{
    this->m_pFly = new FlyWithWings();
    this->m_pQuack = new TrueQuack();
}

RedHeadDuck::RedHeadDuck()
{
    this->m_pFly = new FlyNoWay();
    this->m_pQuack = new TrueQuack();
}

RubberDuck::RubberDuck()
{
    this->m_pFly = new FlyNoWay();
    this->m_pQuack = new Squeak();
}

DecoyDuck::DecoyDuck()
{
    this->m_pFly = new FlyNoWay();
    this->m_pQuack = new MuteQuack();
}
            个人感悟:待留