这有一道南大设计模式题,感觉有点问题表述的不是很清楚,用观察者模式

img

得分
6、(本题满分12分)
用observer模式编写程序:
口Student:有三个私有属性IDname,birthday;
Display:
Displayl:display(ID,name),显示ID+name
Display2:display(ID,birthday),显示ID+birthday
Display3:modify(ID,name,birthday).修改student的三个列
Display 1~2 为observer, Student为 subject
实现每次Display3中实现修改后Display1~2自动更新:

package com.lgr.vo;

class Student{
    int id;
    String name;
    String birthday;
    public void display1(int id,String name) {
        this.id = id;
        this.name = name;
        System.out.println("id="+id+",name="+name);
    }
    public void display2(int id,String birthday) {
        System.out.println("id="+id+",birthday="+birthday);
    }
    public void display3(int id,String name,String birthday) {
        System.out.println("id="+id+",name="+name+",birthday="+birthday);
        display1(id,name);
        display1(id,birthday);
        
    }
}
public class StudentTest {

    public static void main(String[] args) {
        Student subject = new Student();
        subject.display3(1001, "张三", "2021-6-8");

    }

}

img