c言語オブジェクト向けプログラミング

#include <stdio.h>
#include <stdlib.h>

/*
 *
 *   1.              c         
 *   2.     ：        
 *   3.                        
 */

//  
typedef struct _Shape Shape;

//      
struct ShapeClass
{
    void (*construct)(Shape* self); //    
    void (*destroy)(Shape* self);   //    
    void (*draw)(Shape* self);      //      
};

struct _Shape
{
   struct ShapeClass *kclass;
   int x,y;
};

//    
void Shape_construct(Shape* self)
{q
    
     self->x = 0;
     self->y = 0;
     printf("Shape construct
");
}

//    
void Shape_destroy(Shape* self)
{
    printf("shape destroy
");
    //to-do destroy self
}
void Shape_draw(Shape* self)
{
    printf("draw:%d,%d
",self->x,self->y);
    //to-do draw self
}

//  _shape_class,        
struct ShapeClass _shape_class=
{
    Shape_construct,  //          
    Shape_destroy,
    Shape_draw,
};


Shape* newShape()
{
    Shape* s = (Shape*)malloc(sizeof(Shape));
    s->kclass = &_shape_class;
    s->kclass->construct(s);
    return s;
}
void deleteShape(Shape* shape)
{
   shape->kclass->destroy(shape);
   free(shape);
}

int main()
{
    Shape* shape = newShape();
    shape->kclass->draw(shape);
    deleteShape(shape);
}