C++ 享元模式 （FlyWeight Pattern）

//UtilTool.h

//工具头文件

#pragma once

#include <iostream>

#include <string>

#include <map>

using namespace std;

//UObject.h

//根基类，本想多写一些东西的，奈何时间不允许#include "UtilTool.h"

class UObject

{

public :

    UObject(string name, string Description) :Name(name), Description(Description) { Id += 1; };

    static long long GetId();

    string GetName();

    string GetDescription();

    bool SetName(string name);

    bool SetDescription(string des);

    inline void ShowUObject()

    {

        cout <<"<--Id-->"<<Id<< "<--Name-->" << Name << "," << "<--Description-->" << Description <<endl;

    }

private:

    static long long Id;

    string Name;

    string Description;

};

//Texture.h

#include "UObject.h"

class Texture:UObject

{

public:

    Texture(int width =1024, int height =1024) :UObject(NULL, NULL),mWidth(width),mHeight(height) {};

    Texture(string name, string des, int width, int height) :UObject(name,des),mWidth(width),mHeight(height){}

    int mWidth;

    int mHeight;

    inline void ShowTexture()

    {

        UObject::ShowUObject();

        cout << "<--mWidth-->" << mWidth << "<--mHeight-->" << mHeight << endl;

    }

}

//Mesh.h

#include "UObject.h"

class Mesh:UObject

{

public:

    Mesh(string anim=NULL,string skt=NULL):UObject(NULL,NULL),Animation(anim),Skeleton(skt){};

    Mesh(string name, string des, string anim, string skeleton):UObject(name,des),Animation(anim),Skeleton(skeleton){};

    string Animation;

    string Skeleton;

    inline void ShowMesh()

    {

       UObject::ShowUObject();

       cout << "<--Animation-->" << Animation << "<--Skeleton-->" << Skeleton << endl;

    }

};

//RootTree.h

#include "UObject.h"

#include "Mesh.h"

#include "Texture.h"

#include "ResourceFactory.h"

class RootTree:UObject

{

public:

    RootTree(string name,string des):UObject(name,des)

    {

        if(name.length()!=0)

        mTreeMesh = ResourceFactory::GetMesh(name);

        mTreeTexture = ResourceFactory::GetTexture(name);

    }

    void ShowRootTree();

private:

    Mesh* mTreeMesh;

    Texture* mTreeTexture;

};

//ResourceFactory.h

#include "UtilTool.h"

class Mesh;

class Texture;

typedef pair<string, Mesh> PairMesh;

typedef pair<string, Texture> PairTexture;

class ResourceFactory

{

private:

     static map<string, Mesh> *mMapMeshs;

     static map<string, Texture>*mMapTextrues;

     ~ResourceFactory() { if(mMapMeshs!=NULL)delete mMapMeshs;if(mMapTextrues!=NULL) delete mMapTextrues; }

public:

    static Mesh* GetMesh(const string& name);

    static Texture* GetTexture(const string& name);

};

//UObject.cpp

#include "UObject.h"

long long UObject::Id = 0;

long long UObject::GetId()

{

    return Id;

}

string UObject::GetName()

{

    return Name;

}

string UObject::GetDescription()

{

    return Description;

}

bool UObject::SetName(string name)

{

    Name = name;

    return true;

}

bool UObject::SetDescription(string des)

{

    Description = des;

    return true;

}

//RootTree.cpp

#include "RootTree.h"

void RootTree::ShowRootTree()

{   

    if (!RootTree::UObject::GetName().empty())

        cout << "RootTree :" <<RootTree::UObject::GetName()<< "====================" << endl;

    if(mTreeMesh!=NULL)

    mTreeMesh->ShowMesh();

    if(mTreeTexture!=NULL)

    mTreeTexture->ShowTexture();

}

//ResourceFactory.cpp

#include "UtilTool.h"

#include "Mesh.h"

#include "Texture.h"

#include "ResourceFactory.h"

#include "UObject.h"

map<string, Mesh>* ResourceFactory::mMapMeshs = new map<string, Mesh>();

map<string, Texture>* ResourceFactory::mMapTextrues = new map<string, Texture>();

Mesh* ResourceFactory::GetMesh(const string& name)

{

    map<string, Mesh>::iterator itor;

    itor = (*mMapMeshs).find(name);

    if (itor != mMapMeshs->end())

    {

        return &itor->second;

    }

    else

    {

    Mesh* mesh = new Mesh("Mesh 0"+to_string(UObject::GetId()),"This is "+to_string(UObject::GetId())+"th Mesh","Basic Anim","root");

    mMapMeshs->insert(PairMesh(name,*mesh));

    return mesh;

    }

}

Texture* ResourceFactory::GetTexture(const string& name)

{

    map<string, Texture>::iterator itor;

    itor = mMapTextrues->find(name);

    if (itor != mMapTextrues->end())

    {

        return &itor->second;

    }

    else

    {

    Texture* texture = new Texture("Texture 0" +to_string(UObject::GetId()), "This is " + to_string(UObject::GetId()) + "th Mesh", 1024,1024);

    mMapTextrues->insert(PairTexture(name,*texture));

    return  texture;

    }

}

//test .cpp

#include "RootTree.h"

int main()

{

    string firstTree("aspen");

    string firstTreeDes("Populustremula");

    RootTree rt1(firstTree,firstTreeDes);

    rt1.ShowRootTree();

    string SecondTree("peach");

    string SecondTreeDes("Eattingquickly");

    RootTree rt2(SecondTree,SecondTreeDes);

    string ThirdTreeDes("shsodf");

    string ThirdTree("banana");

    RootTree rt3(ThirdTree,ThirdTreeDes);

    string FourthTree("aspen");

    string FourthTreeDec("dfasdfa");

    RootTree rt4(FourthTree,FourthTreeDec);

    rt2.ShowRootTree();

    rt3.ShowRootTree();

    rt4.ShowRootTree();

    system("pause");

    return 0;

}

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