zoukankan      html  css  js  c++  java
  • 设计模式-FlyWeight(结构型模式) 针对 需要创建大量对象的情形,被共享的状态作为内部状态,不被共享的状态作为外部状态

    以下代码来源: 设计模式精解-GoF 23种设计模式解析附C++实现源码

    //Flyweight.h

    #pragma once
    #include<string>
    class FlyWeight
    {
    public:
        virtual ~FlyWeight();
        virtual void Operation(const std::string & extrinsicState);
        std::string GetIntrinsicState();
    protected:
        FlyWeight(std::string intrinsicState);
    private:
        std::string _intrinsicState;
    };
    
    class ConcreateFlyWeight :public FlyWeight
    {
    public:
        ConcreateFlyWeight(std::string intrinsicState);
        ~ConcreateFlyWeight();
        void Operation(const std::string& extrinsicState);
    protected:
    private:
    };

    //Flyweight.cpp

    #include"Flyweight.h"
    #include<iostream>
    
    FlyWeight::FlyWeight(std::string intrinsicState)
    {
        this->_intrinsicState = intrinsicState;
    }
    FlyWeight::~FlyWeight(){}
    void FlyWeight::Operation(const std::string& extrinsicState)
    {
    
    }
    std::string FlyWeight::GetIntrinsicState()
    {
        return this->_intrinsicState;
    }
    ConcreateFlyWeight::ConcreateFlyWeight(std::string intrinsicState) :FlyWeight(intrinsicState)
    {
        std::cout << "ConcreateFlyWeight Build..." << intrinsicState << std::endl;
    }
    ConcreateFlyWeight::~ConcreateFlyWeight(){}
    void ConcreateFlyWeight::Operation(const std::string& extrinsicState)
    {
        std::cout << "ConcreateFlyWeight:内部[" << this->GetIntrinsicState() << "]外部[" << extrinsicState << "]" << std::endl;
    }

    //FlyWeightFactory.h

    #pragma once
    
    #include"Flyweight.h"
    #include<vector>
    #include<string>
    
    class FlyWeightFactory
    {
    public:
        FlyWeightFactory();
        ~FlyWeightFactory();
        FlyWeight* GetFlyWeight(const std::string& key);
    protected:
    private:
        std::vector<FlyWeight*>_fly;
    };

    //FlyWeightFactory.cpp

    #include"FlyWeightFactory.h"
    #include<iostream>
    #include<string>
    
    FlyWeightFactory::FlyWeightFactory(){}
    FlyWeightFactory::~FlyWeightFactory(){}
    FlyWeight* FlyWeightFactory::GetFlyWeight(const std::string& key)
    {
        for (std::vector<FlyWeight*>::iterator it = _fly.begin(); it != _fly.end(); ++it)
        {
            if ((*it)->GetIntrinsicState() == key)
            {
                std::cout << "Already created by users..." << std::endl;
                return *it;
            }
        }
        FlyWeight* fn = new ConcreateFlyWeight(key);
        _fly.push_back(fn);
        return fn;
    }

    //main.cpp

    #include"Flyweight.h"
    #include"FlyWeightFactory.h"
    #include<string>
    int main(int args, char* argv)
    {
        FlyWeightFactory* flyfac = new FlyWeightFactory();
        FlyWeight* fw1 = flyfac->GetFlyWeight("Hello");
        FlyWeight* fw2 = flyfac->GetFlyWeight("World");
        FlyWeight* fw3 = flyfac->GetFlyWeight("Hello");
        getchar();
        return 0;
    
    }
  • 相关阅读:
    MAC配置DNS服务器
    真机IOS8.3以上的文件夹共享
    appium + python的环境配置_windows
    python 的时间与日期
    sublimetext 2 编译文件带input时 提示 EOFError: EOF when reading a line
    cmd无法输入中文解决方案
    配置python学习环境遇到的问题:[Decode error
    monkey初接触
    Android logcat输出中文乱码
    运行 命令框不记录打过的命令,重启后CMD里面是空的.上次打过的命令消失了.
  • 原文地址:https://www.cnblogs.com/fourmi/p/12077831.html
Copyright © 2011-2022 走看看