适配器模式 Adapter

适配器模式，调整使之符合另一接口

1类适配器模式，子类继承Adaptee类

#include <IOSTREAM>
using namespace std;
//类适配器

class Target{
public:
    virtual void action() = 0;
};

class Adaptee{
public:
    void Adapteraction(){
        cout<<"hello world"<<endl;
    }
};

class Adapter:public Target,Adaptee{
public:
    void action(){
        this->Adapteraction();
    }
};    

int main(int argc, char* argv[])
{
    Target * p = new Adapter;
    p->action();
    delete p;
    return 0;
}

2对象适配器模式，将Adaptee类作为对象存在于Adapter类中，在Adapter类中由Target继承来的接口中调用Adaptee的操作

//对象适配器

class Target{
public:
    virtual void action() = 0;
};

class Adaptee{
public:
    void Adapteraction(){
        cout<<"hello world"<<endl;
    }
};

class Adapter:public Target{
public:
    void action(){
        p->Adapteraction();
    }
    Adapter(){
        p = new Adaptee;
    }
    ~Adapter(){
        delete p;
    }
private:
    Adaptee * p;
};    

int main(int argc, char* argv[])
{
    Target * p = new Adapter;
    p->action();
    delete p;
    return 0;
}

3.缺省适配器模式,

我们将这个中间过渡类称为 “缺省适配类”,缺省适配模式为一个接口提供缺省实现

#include <IOSTREAM>
using namespace std;
//缺省适配器

class Target{
public:
    virtual void action1() = 0;
    virtual void action2() = 0;
    virtual void action3() = 0;
};

class DefaultAdapter:public Target{
public:
    void action1(){
        cout<<"action1"<<endl;
    }
    void action2(){
        cout<<"action2"<<endl;
    }
    void action3(){
        cout<<"action3"<<endl;
    }
};

class Adapter:public DefaultAdapter{
public:
    void action1(){
        cout<<"only want action1"<<endl;
    }
};    

int main(int argc, char* argv[])
{
    Target * p = new Adapter;
    p->action1();
    delete p;
    return 0;
}