package bean;
public class Student {
String name;
String studentId;
String sex;
int grade;
public Student(String name，String studentId，String sex，int grade){
this.name= name;
this.studentId= studentId;
this.sex = sex;
this.grade = grade;
}
public int getGrade(){
return grade;
}
public String getName(){
return name;
}
public String getSex(){
return sex;
}
public void setGrade(int g){
this.grade = g;
}
public String getStudentId(){
return studentId;
}
}

System.out.println("***************");
  System.out.println("*歡迎來到學(xué)生管理系統(tǒng) *");
  System.out.println("*1：增加學(xué)生                    *");
  System.out.println("*2：刪除學(xué)生                    *");
  System.out.println("*3：修改成績(jī)                    *");
  System.out.println("*4：查詢成績(jī)                    *");
  System.out.println("***************");
  System.out.println("您想選擇的操作是：");

package test;
import java.util.*;
import bean.Student;
public class Manager {
static List<Student> StudentList = new LinkedList<Student>();
public static void main(String[] agrs){
select(StudentList);
}
private static void select(List<Student> StudentList ){
System.out.println("***************");
System.out.println("*歡迎來到學(xué)生管理系統(tǒng) *");
System.out.println("*1：增加學(xué)生                    *");
System.out.println("*2：刪除學(xué)生                    *");
System.out.println("*3：修改成績(jī)                    *");
System.out.println("*4：查詢成績(jī)                    *");
System.out.println("***************");
System.out.println("您想選擇的操作是：");
Scanner sc = new Scanner(System.in);
int choice = sc.nextInt();
switch(choice){
//增加學(xué)生
case 1:
System.out.print("請(qǐng)輸入學(xué)生的姓名：");
Scanner Sname = new Scanner(System.in);
String name = Sname.nextLine();
System.out.print("請(qǐng)輸入學(xué)生的性別：");
Scanner Ssex = new Scanner(System.in);
String sex = Ssex.nextLine();
System.out.print("請(qǐng)輸入學(xué)生的學(xué)號(hào)：");
Scanner SId = new Scanner(System.in);
String studentId = SId.nextLine();
System.out.print("請(qǐng)輸入學(xué)生的成績(jī)：");
Scanner Sgrade = new Scanner(System.in);
int grade = Sgrade.nextInt();
StudentList.add(new Student(name，studentId，sex，grade));
System.out.println("添加成功?。。。。?);
select(StudentList);
break;
//刪除學(xué)生成績(jī)
case 2:
System.out.print("請(qǐng)告訴我需要?jiǎng)h除學(xué)生的學(xué)號(hào)：");
Scanner Sid = new Scanner(System.in);
String SstudentId = Sid.nextLine();
boolean isfindDelete = false;
for (int i = 0; i < StudentList.size(); i++) {
if(SstudentId.equals(StudentList.get(i).getStudentId())){
System.out.println("發(fā)現(xiàn)了該學(xué)生，正在刪除...");
StudentList.remove(i);
System.out.println("刪除成功!!!");
isfindDelete =true;
}
}
if(!isfindDelete){
System.out.println("抱歉，沒有找到");
}
select(StudentList);
break;
//修改學(xué)生成績(jī)
case 3:
System.out.print("請(qǐng)告訴我需要修改成績(jī)學(xué)生的學(xué)號(hào)：");
Scanner GId = new Scanner(System.in);
String GstudentId = GId.nextLine();
boolean isfindChange = false;
for (int j = 0; j < StudentList.size(); j++) {
if(GstudentId.equals(StudentList.get(j).getStudentId())){
System.out.println("發(fā)現(xiàn)了該學(xué)生，正在修改...");
System.out.println("學(xué)生原成績(jī)?yōu)?+StudentList.get(j).getGrade());
System.out.print("請(qǐng)輸入修改后學(xué)生的成績(jī)：");
Scanner Ggrade = new Scanner(System.in);
int grade2 = Ggrade.nextInt();
StudentList.get(j).setGrade(grade2);
System.out.println("修改成功!!!");
isfindChange =true;
}else{
}
}
if(!isfindChange){
System.out.println("抱歉，沒有找到");
}
select(StudentList);
break;
//查看學(xué)生成績(jī)
case 4:
System.out.print("請(qǐng)告訴我需要查詢學(xué)生的學(xué)號(hào)：");
Scanner CId = new Scanner(System.in);
String CstudentId = CId.nextLine();
boolean isfindData = false;
for (int i = 0; i < StudentList.size(); i++) {
if(CstudentId.equals(StudentList.get(i).getStudentId())){
System.out.println("名字:"+StudentList.get(i).getName());
System.out.println("性別:"+StudentList.get(i).getSex());
System.out.println("學(xué)號(hào):"+StudentList.get(i).getStudentId());
System.out.println("成績(jī):"+StudentList.get(i).getGrade());
isfindData = true;
}
}
if(!isfindData){
System.out.println("抱歉，沒有找到");
}
select(StudentList);
break;
default:
System.out.println("您輸入的數(shù)字有誤，請(qǐng)重新輸入：");
break;
}
}
}