﻿<?xml version="1.0" encoding="utf-8" standalone="yes"?><rss version="2.0" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:trackback="http://madskills.com/public/xml/rss/module/trackback/" xmlns:wfw="http://wellformedweb.org/CommentAPI/" xmlns:slash="http://purl.org/rss/1.0/modules/slash/"><channel><title>C++博客-农妇，山泉，有点儿田-随笔分类-Design Pattern</title><link>http://www.cppblog.com/deadpunk/category/4040.html</link><description>我没有技术</description><language>zh-cn</language><lastBuildDate>Mon, 02 Jun 2008 21:10:32 GMT</lastBuildDate><pubDate>Mon, 02 Jun 2008 21:10:32 GMT</pubDate><ttl>60</ttl><item><title>（转）常见设计模式的解析和实现(C++)之一-Factory模式</title><link>http://www.cppblog.com/deadpunk/archive/2007/04/15/21957.html</link><dc:creator>活着就是折腾，所以当然要骠悍的折腾</dc:creator><author>活着就是折腾，所以当然要骠悍的折腾</author><pubDate>Sun, 15 Apr 2007 09:29:00 GMT</pubDate><guid>http://www.cppblog.com/deadpunk/archive/2007/04/15/21957.html</guid><wfw:comment>http://www.cppblog.com/deadpunk/comments/21957.html</wfw:comment><comments>http://www.cppblog.com/deadpunk/archive/2007/04/15/21957.html#Feedback</comments><slash:comments>0</slash:comments><wfw:commentRss>http://www.cppblog.com/deadpunk/comments/commentRss/21957.html</wfw:commentRss><trackback:ping>http://www.cppblog.com/deadpunk/services/trackbacks/21957.html</trackback:ping><description><![CDATA[转自：http://www.cppblog.com/converse/archive/2006/07/20/10269.html

 常见设计模式的解析和实现(C++)之一-Factory模式 
作用:
定义一个用于创建对象的接口，让子类决定实例化哪一个类。Factory Method 使一个类的实例化延迟到其子类。

UML结构图:

抽象基类:
1)Product:创建出来的对象的抽象基类.
2)Factory创建对象的工厂方法的抽象基类.

接口函数:
1)Creator::FactoryMethod:纯虚函数,由派生类实现,创建出对应的Product.

解析:
在这个模式中,有两个抽象基类,一个是Product为创建出来的对象的抽象基类,一个是Factory是工厂的抽象基类,在互相协作的时候都是由相应的Factory派生类来生成Product的派生类,也就是说如果要新增一种Product那么也要对应的新增一个Factory,创建的过程委托给了这个Factory.也就是说一个Factory和一个Product是一一对应的关系.

备注:
设计模式的演示图上把Factory类命名为Creator,下面的实现沿用了这个命名.

演示实现:

1)Factory.h
/********************************************************************
    created:    2006/06/30
    filename:     Factory.h
    author:        李创
                http://www.cppblog.com/converse/

    purpose:    Factory模式的演示代码
*********************************************************************/

#ifndef FACTORY_H
#define FACTORY_H

class Product
{
public:
    Product(){}
    virtual ~Product(){}
};

class ConcreateProduct
    : public Product
{
public:
    ConcreateProduct();
    virtual ~ConcreateProduct();
};

class Creator
{
public:
    Creator(){}
    virtual ~Creator(){}

    void AnOperation();

protected:
    virtual Product* FactoryMethod() = 0;
};

class ConcreateCreator
    : public Creator
{
public:
    ConcreateCreator();
    virtual ~ConcreateCreator();

protected:
    virtual Product* FactoryMethod();
};

#endif


2)Factory.cpp
/********************************************************************
    created:    2006/06/30
    filename:     Factory.cpp
    author:        李创
                http://www.cppblog.com/converse/

    purpose:    Factory模式的演示代码
*********************************************************************/
#include "Factory.h"
#include <iostream>

using namespace std;

ConcreateProduct::ConcreateProduct()
{
    std::cout << "construction of ConcreateProduct\n";
}

ConcreateProduct::~ConcreateProduct()
{
    std::cout << "destruction of ConcreateProduct\n";
}

void Creator::AnOperation()
{
    Product* p = FactoryMethod();

    std::cout << "an operation of product\n";
}

ConcreateCreator::ConcreateCreator()
{
    std::cout << "construction of ConcreateCreator\n";
}

ConcreateCreator::~ConcreateCreator()
{
    std::cout << "destruction of ConcreateCreator\n";
}

Product* ConcreateCreator::FactoryMethod()
{
    return new ConcreateProduct();
}


3)Main.cpp(测试代码)
/********************************************************************
    created:    2006/06/30
    filename:     Main.cpp
    author:        李创
                http://www.cppblog.com/converse/

    purpose:    测试Factory模式的代码
*********************************************************************/

#include "Factory.h"
#include <stdlib.h>

int main(int argc,char* argv[])
{
    Creator *p = new ConcreateCreator();
    p->AnOperation();

    delete p;

    system("pause");

    return 0;
}<img src ="http://www.cppblog.com/deadpunk/aggbug/21957.html" width = "1" height = "1" /><br><br><div align=right><a style="text-decoration:none;" href="http://www.cppblog.com/deadpunk/" target="_blank">活着就是折腾，所以当然要骠悍的折腾</a> 2007-04-15 17:29 <a href="http://www.cppblog.com/deadpunk/archive/2007/04/15/21957.html#Feedback" target="_blank" style="text-decoration:none;">发表评论</a></div>]]></description></item></channel></rss>