2023/10/24 每日总结
今天完成了设计模式实验20
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)。
源代码
package org.test20; import java.util.ArrayList; import java.util.List; public class Caretaker { private List<Memento> list=new ArrayList<>(); public Memento getMemento() { Memento mm=list.get(list.size()-2); list.remove(list.size()-2); return mm; } public void setMemento(Memento memento) { list.add(memento); } } package org.test20; public class Client { public static void main(String[] args) { // TODO Auto-generated method stub UserInfo user=new UserInfo(); Caretaker c=new Caretaker(); user.setAccount("zhangsan"); user.setPassword("123456"); System.out.println("status1:"); user.show(); c.setMemento(user.saveMemento()); System.out.println("*************"); user.setPassword("111111"); System.out.println("status2:"); user.show(); c.setMemento(user.saveMemento()); System.out.println("*************"); user.setPassword("zyx666"); System.out.println("status3:"); user.show(); c.setMemento(user.saveMemento()); System.out.println("*************"); user.setPassword("777777"); System.out.println("status4:"); user.show(); c.setMemento(user.saveMemento()); System.out.println("*************"); user.restoreMemento(c.getMemento()); System.out.println("back to status3:"); user.show(); System.out.println("*************"); user.restoreMemento(c.getMemento()); System.out.println("back to status2:"); user.show(); System.out.println("*************"); user.restoreMemento(c.getMemento()); System.out.println("back to status1:"); user.show(); System.out.println("*************"); } } package org.test20; import java.util.ArrayList; import java.util.List; public class Memento { 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(String account, String password, String telNo) { this.account = account; this.password = password; this.telNo = telNo; } } package org.test20; public class UserInfo { 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("Account:"+this.account); System.out.println("Password:"+this.password); System.out.println("TelNo:"+this.telNo); } }