Adapter Design Pattern in C++

Adapter Design pattern converts the interface of a class into another interface that clients expect.

#include

 

using namespace std;

 

class Circle

{

 public:

    virtual void draw() = 0;

};

 

class StandardCircle

{

public:

    StandardCircle(double radius)

    {

      radius_ = radius;

        cout << "StandardCircle:  create. radius = "<< radius_ << endl;

    }

    

private:

    double radius_ ;

};

 

class CAdapter : public Circle, private StandardCircle  //Adapter Class

{

public:

    CAdapter( double diameter)

        : StandardCircle(diameter/2)

    {

        cout << "CAdapter: create. diameter = " << diameter << endl;

    }

    virtual void draw()

    {

        cout << "CAdapter: draw." << endl;

        oldDraw();

    }

};

 

int main()

{

    Circle*  c = new CAdapter(14);

    c->draw();

}