C++ 享元模式（FlyWeight Pattern）

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//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;
}