[设计模式] 设计模式课程（十八）--迭代器模式

 1 template<typename T>
 2 class Iterator
 3 {
 4 public:
 5     virtual void first() = 0;
 6     virtual void next() = 0;
 7     virtual bool isDone() const = 0;
 8     virtual T& current() = 0;
 9 };
10 
11 template<typename T>
12 class MyCollection{
13     
14 public:
15     
16     Iterator<T> GetIterator(){
17         //...
18     }
19     
20 };
21 
22 template<typename T>
23 class CollectionIterator : public Iterator<T>{
24     MyCollection<T> mc;
25 public:
26     
27     CollectionIterator(const MyCollection<T> & c): mc(c){ }
28     
29     void first() override {
30         
31     }
32     void next() override {
33         
34     }
35     bool isDone() const override{
36         
37     }
38     T& current() override{
39         
40     }
41 };
42 
43 void MyAlgorithm()
44 {
45     MyCollection<int> mc;
46     
47     Iterator<int> iter= mc.GetIterator();
48     
49     for (iter.first(); !iter.isDone(); iter.next()){
50         cout << iter.current() << endl;
51     }
52     
53 }