Factory Pattern

1.Factory模式两个最重要的功能

（1）定义创建对象的接口，封装了对象的创建。

（2）使得具体化类的工作延迟到了子类中。

2.Factory模式结构示意图

3.实现

#ifndef _PRODUCT_H_
#define _PRODUCT_H_

class Product
{
public:
    virtual ~Product() = 0;
protected:
    Product();
private:
};

class ConcreteProduct:public Product
{
public:
    ~ConcreteProduct();
    ConcreteProduct();
protected:
private:
};

#endif

#include "Product.h"
#include <iostream>
using namespace std;

Product::Product()
{

}
Product::~Product()
{

}

ConcreteProduct::ConcreteProduct()
{
    cout<<"ConcreteProduct..."<<endl;
}
ConcreteProduct::~ConcreteProduct()
{

}

#ifndef _FACTORY_H_
#define _FACTORY_H_

class Product;

class Factory
{
public:
    virtual ~Factory() = 0;
    virtual Product* CreateProduct() = 0;
protected:
    Factory();
private:
};

class ConcreteFactory:public Factory
{
public:
    ~ConcreteFactory();
    ConcreteFactory();
    Product* CreateProduct();
protected:
private:
};
#endif

#include "Factory.h"
#include "Product.h"

#include <iostream>
using namespace std;

Factory::Factory()
{

}
Factory::~Factory()
{

}
ConcreteFactory::ConcreteFactory()
{
    cout<<"ConcreteFactory....."<<endl;
}
ConcreteFactory::~ConcreteFactory()
{

}
Product* ConcreteFactory::CreateProduct()
{
    return new ConcreteProduct();
}