1 #include <iostream>  2 #include <string>  3 using namespace std;  4   5 class IUser  6 {  7 public:  8     virtual void getUser() = 0;  9     virtual void setUser() = 0; 10 }; 11  12 class SqlUser : public IUser 13 { 14 public: 15     void getUser() 16     { 17         cout << "在sql中返回user" << endl; 18     } 19     void setUser() 20     { 21         cout << "在sql中设置user" << endl; 22     } 23 }; 24  25 class AccessUser : public IUser 26 { 27 public: 28     void getUser() 29     { 30         cout << "在Access中返回user" << endl; 31     } 32     void setUser() 33     { 34         cout << "在Access中设置user" << endl; 35     } 36 }; 37  38 class IDepartment 39 { 40 public: 41     virtual void getDepartment() = 0; 42     virtual void setDepartment() = 0; 43 }; 44  45 class SqlDepartment : public IDepartment 46 { 47 public: 48     void getDepartment() 49     { 50         cout << "在sql中返回Department" << endl; 51     } 52     void setDepartment() 53     { 54         cout << "在sql中设置Department" << endl; 55     } 56 }; 57  58 class AccessDepartment : public IDepartment 59 { 60 public: 61     void getDepartment() 62     { 63         cout << "在Access中返回Department" << endl; 64     } 65     void setDepartment() 66     { 67         cout << "在Access中设置Department" << endl; 68     } 69 }; 70  71 class IFactory 72 { 73 public: 74     virtual IUser *createUser() = 0; 75     virtual IDepartment *createDepartment() = 0; 76 }; 77  78 class SqlFactory : public IFactory 79 { 80 public: 81     IUser *createUser()  82     { 83         return new SqlUser(); 84     } 85     IDepartment *createDepartment()  86     { 87         return new SqlDepartment(); 88     } 89 }; 90  91 class AccessFactory : public IFactory 92 { 93 public: 94     IUser *createUser() 95     { 96         return new AccessUser(); 97     } 98     IDepartment *createDepartment()  99     {100         return new AccessDepartment();101     }102 };103 104 /*************************************************************/105 106 class DataAccess107 {108 private:109     static string db;110 public:111     static IUser *createUser()112     {113         if (db == "access")114         {115             return new AccessUser();116         }117         else if (db == "sql")118         {119             return new SqlUser();120         }121     }122     static IDepartment *createDepartment()123     {124         if (db == "access")125         {126             return new AccessDepartment();127         }128         else if (db == "sql")129         {130             return new SqlDepartment();131         }    132     }133 };134 135 string DataAccess::db = "sql";136 137 /*************************************************************/138 139 int main()140 {141     IFactory *factory;142     IUser *user;143     IDepartment *department;144 145     factory = new AccessFactory();146     user = factory->createUser();147     department = factory->createDepartment();148     149     user->getUser();150     user->setUser();151     department->getDepartment();152     department->setDepartment();153 154     user = DataAccess::createUser();155     department = DataAccess::createDepartment();156 157     user->getUser();158     user->setUser();159     department->getDepartment();160     department->setDepartment();161 162     return 0;163 }