设计模式9、组合模式 Composite

#pragma once
#include 
#include 
/****组合模式 Composite******/
using namespace std;
class Component
{
public:
       Component(string name) : m_strName(name) {}
       virtual ~Component() {}
       virtual void Add(Component* cmpt) = 0;  // 添加构件
       virtual void Remove(Component* cmpt) = 0;  // 删除构件
       virtual Component* GetChild(int index) = 0;  // 获取构件
       virtual void Operation(int indent) = 0;  // 显示构件（以缩进的方式）
private:
       Component();  // 不允许
protected:
       string m_strName;
};
 
#pragma once
#include 
#include "component.h"
#ifndef SAFE_DELETE
#define SAFE_DELETE(p) { if(p){delete(p); (p)=NULL;} }
#endif
class Composite : public Component
{
public:
       Composite(string name) : Component(name) {}
       virtual ~Composite() {
              while (!m_elements.empty()) {
                     vector::iterator it = m_elements.begin();
                     SAFE_DELETE(*it);
                     m_elements.erase(it);
              }
       }
       void Add(Component* cmpt) {
              m_elements.push_back(cmpt);
       }
       void Remove(Component* cmpt) {
              vector::iterator it = m_elements.begin();
              while (it != m_elements.end()) {
                     if (*it == cmpt) {
                           SAFE_DELETE(cmpt);
                           m_elements.erase(it);
                           break;
                     }
                     ++it;
              }
       }
       Component* GetChild(int index) {
              if (index >= m_elements.size())
                     return NULL;
              return m_elements[index];
       }
       // 递归显示
       void Operation(int indent) {
              string newStr(indent, '-');
              cout << newStr << "+ " << m_strName << endl;
              // 显示每个节点的孩子
              vector::iterator it = m_elements.begin();
              while (it != m_elements.end()) {
                     (*it)->Operation(indent + 2);
                     ++it;
              }
       }
private:
       Composite();  // 不允许
private:
       vector m_elements;
};
 
#pragma once
#include "component.h"
class Leaf : public Component
{
public:
       Leaf(string name) : Component(name) {}
       virtual ~Leaf() {}
       void Add(Component* cmpt) {
              cout << "Can't add to a Leaf" << endl;
       }
       void Remove(Component* cmpt) {
              cout << "Can't remove from a Leaf" << endl;
       }
       Component* GetChild(int index) {
              cout << "Can't get child from a Leaf" << endl;
              return NULL;
       }
       void Operation(int indent) {
              string newStr(indent, '-');
              cout << newStr << " " << m_strName << endl;
       }
private:
       Leaf();  // 不允许
};
 
#include "composite.h"
#include "leaf.h"
int main()
{
       // 创建一个树形结构
       // 创建根节点
       Component* pRoot = new Composite("江湖公司（任我行）");
       // 创建分支
       Component* pDepart1 = new Composite("日月神教（东方不败）");
       pDepart1->Add(new Leaf("光明左使（向问天）"));
       pDepart1->Add(new Leaf("光明右使（曲洋）"));
       pRoot->Add(pDepart1);
       Component* pDepart2 = new Composite("五岳剑派（左冷蝉）");
       pDepart2->Add(new Leaf("嵩山（左冷蝉）"));
       pDepart2->Add(new Leaf("衡山（莫大）"));
       pDepart2->Add(new Leaf("华山（岳不群）"));
       pDepart2->Add(new Leaf("泰山（天门道长）"));
       pDepart2->Add(new Leaf("恒山（定闲师太）"));
       pRoot->Add(pDepart2);
       // 添加和删除叶子
       pRoot->Add(new Leaf("少林（方证大师）"));
       pRoot->Add(new Leaf("武当（冲虚道长）"));
       Component* pLeaf = new Leaf("青城（余沧海）");
       pRoot->Add(pLeaf);
       // 小丑，直接裁掉
       pRoot->Remove(pLeaf);
       // 递归地显示组织架构
       pRoot->Operation(1);
       // 删除分配的内存
       SAFE_DELETE(pRoot);
       getchar();
       return 0;
}