职责链模式（Chain of Responsibility）

2015/5/18
职责链模式（Chain of Responsibility）:
避免发送者和接受者之间的耦合关系，将对象练成一条链，并沿着这条链传递该请求，直到有一个对象处理它为止。
优点：发送者不用考虑众多接受者之间的数据流，简化了对象的相互链接（仅保持指向后继）。
代码如下：

#include <iostream>
#include <vector>
using namespace std;
/*
  职责链模式实现
  逐级判断职责 
*/
class Manager{
    private:
        string name;
        vector <string> ver;
        Manager *p;
        public:
            Manager(string name)
            {
                this->name = name;
                this->p=NULL;
            }
            void SetLeader(Manager *p)
            {
                this->p=p;
            }
        void Add(string Res)
        {
            ver.push_back(Res);
        }
        int Respons(string res)
        { 
            typename vector <string>::iterator it;
            for(it=ver.begin();it!=ver.end()&&res!=(*it);it++);
            if(it!=ver.end()){
                cout<<name<<"同意请求"<<endl;
                return 1; 
            }else{
                if(this->p){
                    return this->p->Respons(res);
                }else{
                    return 0;
                }
            }
        }
};
int main(void)
{
    string want;
    Manager *Teacher1=new Manager("校长");
    Manager *Teacher2=new Manager("院长");
    Manager *Teacher3=new Manager("导员");
    Manager *Student1=new Manager("班长");
    Teacher2->SetLeader(Teacher1);
    Teacher3->SetLeader(Teacher2);
    Student1->SetLeader(Teacher3);
    Teacher2->Add("退学");
    Teacher3->Add("请假");
    cout<<"输入请求"<<endl;
     cin>>want;
     if(!Student1->Respons(want)){
     cout<<"请求被驳回"<<endl;
     }
    return 0;
}