adapter pattern

adapter pattern

1.소스

#include <iostream>

using namespace std;

typedef int Coordinate;
typedef int Dimension;

// Desired interface
class Rectangle
{
public:
    virtual void draw() = 0;
};


// Legacy component
class LegacyRectangle
{

public:
    LegacyRectangle(Coordinate x1, Coordinate y1, Coordinate x2, Coordinate y2)
    {
        x1_ = x1;
        y1_ = y1;
        x2_ = x2;
        y2_ = y2;
        cout << "LegacyRectangle:  create.  (" << x1_ << "," << y1_ << ") => ("
          << x2_ << "," << y2_ << ")" << endl;
    }
	
    void oldDraw()
    {
        cout << "LegacyRectangle:  oldDraw.  (" << x1_ << "," << y1_ << 
          ") => (" << x2_ << "," << y2_ << ")" << endl;
    }
	
private:
    Coordinate x1_;
    Coordinate y1_;
    Coordinate x2_;
    Coordinate y2_;
};


// Adapter wrapper
class RectangleAdapter: public Rectangle, private LegacyRectangle
{

public:
    RectangleAdapter(Coordinate x, Coordinate y, Dimension w, Dimension h):
      LegacyRectangle(x, y, x + w, y + h)
    {
        cout << "RectangleAdapter: create.  (" << x << "," << y << 
          "), width = " << w << ", height = " << h << endl;
    }
	
    virtual void draw()
    {
        cout << "RectangleAdapter: draw." << endl;
        oldDraw();
    }
};

int main()
{
   Rectangle *r = new RectangleAdapter(120, 200, 60, 40);
   r->draw();
}

2.결과

g++ -o adapter adapter.cpp
hacker@HACKER:~/cpp$ ./adapter
LegacyRectangle:  create.  (120,200) => (180,240)
RectangleAdapter: create.  (120,200), width = 60, height = 40
RectangleAdapter: draw.
LegacyRectangle:  oldDraw.  (120,200) => (180,240)
hacker@HACKER:~/cpp$