设计模式-简单工厂模式

// Product.h

#ifndef _PRODUCT_H_
#define _PRODUCT_H_

class Product
{
protected:
	Product();

public:
	virtual ~Product() = 0;
};

// 这里可以有多个Product子类
class ConcreteProduct : public Product
{
public:
	~ConcreteProduct();
	ConcreteProduct();
};

#endif // _PRODUCT_H_

// Product.cpp

#include <iostream>
using namespace std;

#include "Product.h"

Product::Product()
{
	cout << "Product::Product" << endl;
}

Product::~Product()
{
	cout << "Product::~Product" << endl;
}

///////////////////////////////////////////

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

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

// Factory.h

#ifndef _FACTORY_H_
#define _FACTORY_H_

class Product;

class Factory
{
protected:
	Factory();

public:
	virtual ~Factory() = 0;
	virtual Product* CreateProduct() = 0;
};

class ConcreteFactory : public Factory
{
public:
	ConcreteFactory();
	~ConcreteFactory();
	Product* CreateProduct();
};

#endif // _FACTORY_H_

// Factory.cpp

#include <iostream>
using namespace std;

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

Factory::Factory()
{
	cout << "Factory::Factory" << endl;
}

Factory::~Factory()
{
	cout << "Factory::~Factory" << endl;
}


/////////////////////////////////////////////////

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

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

// 可以通过传不同的参数来创建不同的产品
Product* ConcreteFactory::CreateProduct()
{
	return new ConcreteProduct();
}

// main.cpp

#include <iostream>
using namespace std;

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

#define IF_EXIST_DELETE(OBJECT) \
{ \
	if (OBJECT) \
	{ \
		delete OBJECT; \
		OBJECT = NULL; \
	} \
}

int main(int argc, char *argv[])
{
	Factory *factory = new ConcreteFactory();
	Product *product  = factory->CreateProduct();

	IF_EXIST_DELETE(product);
	IF_EXIST_DELETE(factory);

	system("pause");
	return 0;
}