Composite Pattern

1.将对象组合成树形结构以表示“部分--整体”的层次结构。组合模式使得用户对单个对象和组合对象的使用具有一致性。

2.Composite 模式结构图

3.实现

 1 #ifndef _COMPONENT_H_
 2 #define _COMPONENT_H_
 3
 4 class Component
 5 {
 6 public:
 7     Component();
 8     virtual ~Component();
 9 public:
10     virtual void Operation() = 0;
11     virtual void Add(const Component& );
12     virtual void Remove(const Component& );
13     virtual Component* GetChild(int );
14 protected:
15 private:
16 };
17
18 #endif

Component.h

 1 #include "Component.h"
 2
 3 Component::Component()
 4 {
 5
 6 }
 7 Component::~Component()
 8 {
 9
10 }
11 void Component::Add(const Component& com)
12 {
13
14 }
15 Component* Component::GetChild(int index)
16 {
17     return 0;
18 }
19 void Component::Remove(const Component& com)
20 {
21
22 }

Component.cpp

 1 #ifndef _COMPOSITE_H_
 2 #define _COMPOSITE_H_
 3
 4 #include "Component.h"
 5 #include <vector>
 6 using namespace std;
 7
 8 class Composite:public Component
 9 {
10 public:
11     Composite();
12     ~Composite();
13 public:
14     void Operation();
15     void Add(Component* com);
16     void Remove(Component* com);
17     Component* GetChild(int index);
18 protected:
19 private:
20     vector<Component*> comVec;
21 };
22
23 #endif

Composite.h

 1 #include "Composite.h"
 2 #include "Component.h"
 3 #define NULL 0 //define NULL POINTOR
 4
 5 Composite::Composite()
 6 { //vector<Component*>::iterator itend = comVec.begin();
 7 }
 8 Composite::~Composite()
 9 {
10
11 }
12 void Composite::Operation()
13 {
14     vector<Component*>::iterator comIter = comVec.begin();
15     for (;comIter != comVec.end();comIter++)
16     {
17         (*comIter)->Operation();
18     }
19 }
20 void Composite::Add(Component* com)
21 {
22     comVec.push_back(com);
23 }
24 void Composite::Remove(Component* com)
25 {
26     comVec.erase(&com);
27 }
28 Component* Composite::GetChild(int index)
29 {
30     return comVec[index];
31 }

Composite.cpp

 1 #ifndef _LEAF_H_
 2 #define _LEAF_H_
 3
 4 #include "Component.h"
 5
 6 class Leaf:public Component
 7 {
 8 public:
 9     Leaf();
10     ~Leaf();
11 void Operation();
12 protected:
13 private:
14 };
15
16 #endif

Leaf.h

 1 #include "Leaf.h"
 2 #include <iostream>
 3
 4 using namespace std;
 5
 6 Leaf::Leaf()
 7 {
 8
 9 }
10 Leaf::~Leaf()
11 {
12
13 }
14 void Leaf::Operation()
15 {
16     cout<<"Leaf operation....."<<endl;
17 }

Leaf.cpp

 1 #include "Component.h"
 2 #include "Composite.h"
 3 #include "Leaf.h"
 4 #include <iostream>
 5
 6 using namespace std;
 7
 8 int main(int argc,char* argv[])
 9 {
10     Leaf* l = new Leaf();
11     l->Operation();
12     Composite* com = new Composite();
13     com->Add(l);
14     com->Operation();
15     Component* ll = com->GetChild(0);
16     ll->Operation();
17
18     return 0;
19 }

main.cpp