用模板简化factory的实现

最新推荐文章于 2025-11-07 05:51:56 发布

原创最新推荐文章于 2025-11-07 05:51:56 发布 · 143 阅读

0 ·

CC 4.0 BY-SA版权

文章标签：

#F#

本文通过一个C++示例程序展示了如何使用Boost库中的智能指针管理内存，并结合工厂模式创建对象实例。该程序实现了不同类型的对象创建与销毁的过程跟踪。


// test-object-create-template.cpp : Defines the entry point for the console application.
//

#include "stdafx.h"
#include <boost\ptr_container\ptr_vector.hpp>
#include <iostream>
#include <windows.h>

using namespace std;

class BASE : boost::noncopyable
{
public:
	virtual      ~BASE()   {}
};

class T1 : public BASE{
public:
	T1() {
		cout << "T1 created\n";
	}
	virtual ~T1() {
		cout << "T1 destroied\n";

	}
};

class T2 : public BASE{
public:
	T2() {
		cout << "T2 created\n";
	}
	virtual ~T2() {
		cout << "T2 destroied\n";
	}
};

class Factory {
public:
	boost::ptr_vector<BASE> ptr_set;
	Factory() {

	}
	template<class T>
	T* get() {
		static T* g_ptr = NULL;
		if( !g_ptr ) {
			g_ptr = new T();
			ptr_set.push_back( g_ptr );
		}
		return g_ptr;
	}
};

int _tmain(int argc, _TCHAR* argv[])
{
	{
		boost::ptr_vector<BASE> ptr_set;
		ptr_set.push_back( new T1);
		ptr_set.push_back( new T2);
	}
	{
		Factory f;
		T1* t1 = f.get<T1>();
		T2* t2 = f.get<T2>();
		T1* t3 = f.get<T1>();

		assert( f.ptr_set.size() == 2);

	}
	//delete t1;
	//delete t2;
	Sleep(1000);
	return 0;
}