备忘录模式javac++
软件设计 石家庄铁道大学信息学院
实验 20:备忘录模式
本次实验属于模仿型实验,通过本次实验学生将掌握以下内容:
1、理解备忘录模式的动机,掌握该模式的结构;
2、能够利用备忘录模式解决实际问题。
[实验任务一]:多次撤销
改进课堂上的“用户信息操作撤销”实例,使得系统可以实现多次撤销(可以使用HashMap、ArrayList等集合数据结构实现)。
实验要求:
1. 提交源代码;
2. 注意编程规范。
package test20; public class Caretaker { private Memento[] array = null; private int index; private Memento memento; public Memento getMemento() { return memento; } public void setMemento(Memento memento) { this.memento=memento; } public Caretaker(){ array = new Memento[10]; index = 0; } public void addMemento(Memento Memento){ array[index++] = Memento; } public Memento preMemento(){ Memento pop = null; try { pop = array[--index]; } catch (Exception e) { e.printStackTrace(); } return pop; } }
package test20; public class main { public static void main(String args[]) { UserInfoDTO user = new UserInfoDTO(); Caretaker c = new Caretaker(); user.setAccount("zhangrong"); user.setPassword("123456"); user.setTelNo("130000"); System.out.println("状态一:"); user.show(); c.addMemento(user.saveMemento()); System.out.println("-----------------"); user.setPassword("000000"); user.setTelNo("130111"); System.out.println("状态二:"); user.show(); c.addMemento(user.saveMemento()); System.out.println("-----------------"); user.setPassword("111111"); user.setTelNo("130222"); System.out.println("状态三:"); user.show(); System.out.println("-----------------"); user.restoreMemento(c.preMemento()); System.out.println("回到状态二:"); user.show(); System.out.println("-----------------"); user.restoreMemento(c.preMemento()); System.out.println("回到状态一:"); user.show(); System.out.println("-----------------"); } }
package test20; class Memento { private String account; private String password; private String telNo; public Memento(String account,String password,String telNo) { this.account=account; this.password=password; this.telNo=telNo; } public String getAccount() { return account; } public void setAccount(String account) { this.account=account; } public String getPassword() { return password; } public void setPassword(String password) { this.password=password; } public String getTelNo() { return telNo; } public void setTelNo(String telNo) { this.telNo=telNo; } }
package test20; public class UserInfoDTO { private String account; private String password; private String telNo; public String getAccount() { return account; } public void setAccount(String account) { this.account=account; } public String getPassword() { return password; } public void setPassword(String password) { this.password=password; } public String getTelNo() { return telNo; } public void setTelNo(String telNo) { this.telNo=telNo; } public Memento saveMemento() { return new Memento(account,password,telNo); } public void restoreMemento(Memento memento) { this.account=memento.getAccount(); this.password=memento.getPassword(); this.telNo=memento.getTelNo(); } public void show() { System.out.println("账号是" + this.account); System.out.println("密码是" + this.password); System.out.println("电话是" + this.telNo); } }
#include<iostream> #include<string> #include<vector> using namespace std; //备忘录 class Memento { private: string account; string password; string telNo; public: Memento(string account, string password, string telNo) { this->account = account; this->password = password; this->telNo = telNo; } string getAccount() { return account; } void setAccount(string account) { this->account = account; } string getPassword() { return password; } void setPassword(string password) { this->password = password; } string getTelNo() { return telNo; } void setTelNo(string telNo) { this->telNo = telNo; } }; //发起者 class UserInfoDTO { private: string account; string password; string telNo; public: string getAccount() { return account; } void setAccount(string account) { this->account = account; } string getPassword() { return password; } void setPassword(string password) { this->password = password; } string getTelNo() { return telNo; } void setTelNo(string telNo) { this->telNo = telNo; } Memento saveMemento() { Memento memento(account, password, telNo); return memento; } void restoreMenmento(Memento memento) { this->account = memento.getAccount(); this->password = memento.getPassword(); this->telNo = memento.getTelNo(); } void show() { cout << "帐号:" + this->account << endl; cout << "密码:" + this->password << endl; cout << "电话:" + this->telNo << endl; } }; //管理者 class Caretaker { private: vector<Memento>mementos; public: Memento getMemento(int i) { return mementos.at(i); } void setMemento(Memento memento) { mementos.push_back(memento); } }; //测试函数 int main() { int index = -1; UserInfoDTO user; Caretaker taker; user.setAccount("zhangrong"); user.setPassword("123456"); user.setTelNo("13300000000"); cout << "状态一:" << endl; taker.setMemento(user.saveMemento()); index++; user.show(); cout << "----------------------------------" << endl; user.setPassword("000000"); user.setTelNo("13300001111"); cout << "状态二:" << endl; taker.setMemento(user.saveMemento()); index++; user.show(); cout << "----------------------------------" << endl; user.setPassword("111111"); user.setTelNo("13300002222"); cout << "状态三:" << endl; user.show(); cout << "----------------------------------" << endl; cout << "回到状态二:" << endl; index--; user.restoreMenmento(taker.getMemento(1)); user.show(); cout << "----------------------------------" << endl; cout << "回到状态一:" << endl; index --; user.restoreMenmento(taker.getMemento(0)); user.show(); cout << "----------------------------------" << endl; }