装饰模式

  1 // 装饰模式应用.cpp : 定义控制台应用程序的入口点。
  2 //
  3 
  4 #include "stdafx.h"
  5 #include<iostream>
  6 using namespace std;
  7 
  8 //定义一个纯基类
  9 class Component
 10 {
 11 public:
 12     Component(){}
 13     virtual ~Component(){}
 14     virtual  void operate()=0;
 15 };
 16 
 17 //定义两个需要被装饰的人people1和peopel2
 18 class People1 :public Component
 19 {
 20 public:
 21     People1(){}
 22     virtual ~People1(){}
 23     virtual  void operate(){}
 24 };
 25 class People2 :public Component
 26 {
 27 public:
 28     People2(){}
 29     virtual ~People2(){}
 30     virtual  void operate(){}
 31 };
 32 //定义一个抽象的装饰类
 33 class Decorator :public Component
 34 {
 35 public:
 36     Decorator(Component *cc):ComponentObj(cc){}
 37     //Decorator(Component *cc){}//考虑下如果使用这种构造方式而不是用ComponentObj，并且不对operate()任何操作会对结果产生什么影响
 38     //Decorator(){}//考虑下如果使用这种构造方式会对具体的装饰类产生什么影响
 39     virtual ~Decorator(){}
 40     virtual void operate()
 41     {
 42         if(ComponentObj!=NULL)
 43         {
 44             ComponentObj->operate();
 45         }
 46     }
 47 protected:
 48      Component *ComponentObj;
 49 };
 50 //定义若干个具体的装饰类
 51 class Tshirt:public Decorator
 52 {
 53 public:
 54     Tshirt(Component *com) :Decorator(com){}
 55     //构造Tshirt类的时候需要先构造它的基类Decorator
 56     //而在Decorator类的构造函数Decorator(Component *cc):ComponentObj(cc){}中将输入的值先赋值给ComponentObj了
 57     //将输入参数com复制给Decorator，是为了Decorator::operate();
 58     virtual ~Tshirt(){}
 59     virtual void operate()
 60     {
 61         cout<<"Tshirt"<<endl;
 62         Decorator::operate();
 63     }
 64 };
 65 class Shoes:public Decorator
 66 {
 67 public:
 68     Shoes(Component *com) :Decorator(com){}
 69     virtual ~Shoes(){}
 70     virtual void operate()
 71     {
 72         cout<<"Shoes"<<endl;
 73         Decorator::operate();
 74     }
 75 };
 76 class Suit:public Decorator
 77 {
 78 public:
 79     Suit(Component *com) :Decorator(com){}
 80     virtual ~Suit(){}
 81     virtual void operate()
 82     {
 83         cout<<"Suit"<<endl;
 84         Decorator::operate();
 85     }
 86 };
 87 int _tmain(int argc, _TCHAR* argv[])
 88 {
 89     //新建一个people1
 90     People1 *p1=new People1();
 91     cout<<"Im people1"<<endl;
 92     //给people1穿Tshirt、Suit
 93     Tshirt *T1=new Tshirt(p1);
 94     Suit *S1=new Suit(T1);
 95     S1->operate();
 96 
 97     People2 *p2=new People2();
 98     cout<<"Im people2"<<endl;
 99     //给people1穿Tshirt、Suit
100     Tshirt *T2=new Tshirt(p2);
101     Suit *S2=new Suit(T2);
102     Shoes *SH=new Shoes(S2);
103     SH->operate();
104 
105     return 0;
106 }