工厂方法模式（Factory Method Pattern）

 1 #ifndef FACTORYMETHOD_H
 2 #define FACTORYMETHOD_H
 3 
 4 #include<iostream>
 5 using namespace std;
 6 
 7 class Product//should be a pure virtual class.
 8 {
 9 public:
10     Product(){}
11     ~Product(){}
12 };
13 
14 class ConcreteProductA:public Product
15 {
16 public:
17     ConcreteProductA()
18     {
19         cout<<"ConcreteProductA is created."<<endl;
20     }
21 };
22 
23 class ConcreteProductB:public Product
24 {
25 public:
26     ConcreteProductB()
27     {
28         cout<<"ConcreteProductB is created."<<endl;
29     }
30 };
31 
32 class Creator
33 {
34 public:
35     virtual Product* createProduct()=0;
36 };
37 
38 class ConcreteCreatorA:public Creator
39 {
40 public:
41     Product* createProduct()
42     {
43         return new ConcreteProductA();
44     }
45 };
46 
47 class ConcreteCreatorB:public Creator
48 {
49 public:
50     Product* createProduct()
51     {
52         return new ConcreteProductB();
53     }
54 };
55 
56 #endif//FACTORYMETHOD_H
57 
58 int main()
59 {
60     Creator* creator=new ConcreteCreatorA();
61     creator->createProduct();
62     cout<<endl;
63 
64     creator=new ConcreteCreatorB();
65     creator->createProduct();
66 
67      return 0;
68 }