学生管理系统 Arraylist实现

String s2 = sc.next();
int choice1 = Integer.parseInt(s2);
switch(choice1)
{
case 2:
System.out.println("是否保存？Y/N");
String str2 = sc.next();
int choice2 = Integer.parseInt(str2);
switch(choice2)
{
case 1:
}catch(NumberFormatException e)
{
System.out.print("输入不正确,请重新输入");
}
System.out.print("请输入要删除的学号信息：");
String id4 = sc.next();
me.del(id4);
System.out.print("输入 7 保存，否则你的删除信息不被写入到文件");
try
{
System.out.println("请选择你要查询的关键字：");
System.out.println("1.学号 2.姓名 3.年龄 4.工作");
{
boolean exit = false;
Method me = new Method();
SmsPrint sm = new SmsPrint();
sm.Loginprint();
System.out.println("请选择数字");
Scanner sc = new Scanner(System.in);
System.out.print("输入不正确,请重新输入");
}
break;
case 4:
System.out.println("请输入要查询的工作");
while(login)
{
sm.WelcomePrint();
System.out.println("请选择操作");
System.out.println();
try
{
//me.write();
break;
case 5 :
System.out.println("请输入要修改学生的学号");
String id5 = sc.next();
me.sort();
break;
default:
break;
}
import java.io.*;
import java.util.*;
public class SMS
{
static int i2 = 0 ;
static int i1 = 0 ;
public static void main(String[] args) throws Exception
me.change(id5);
System.out.print("输入 7 保存，否则你的修改信息不被写入到文件");
//me.write();
break;
case 6 :
break;
}
}catch(NumberFormatException e)
{
System.out.print("输入不正确,请重新输入");
String str3 = sc.next();
int choice3 = Integer.parseInt(str3);
switch(choice3)
{
case 1:
}
else
{
System.out.print("已成功退出");
}
exit = true;
break Outer;
}
break;
case 7:
System.out.println("保存学生的信息");
me.write();
exit = true;
System.out.println("请输入要查询的姓名");
String name6me(name6);
break;
me.list = me.read();
me.showall();
break;
case 2:
me.list = me.read();
String store = sc.next();
if(store.equals("Y")||store.equals("y"))
{
me.write();
System.out.print("已成功退出");
System.out.println("请输入要查询的学号");
String id6 = sc.next();
me.check(id6);
break;
case 2:
case 1:
System.out.println("你选择了登录");
Outer:
for(int i=0;i<3;i++)
{
System.out.println("请输入用户名：");
String name = sc.next();
break;
case 8:
try
{
System.out.println("显示所有学生的信息");
System.out.println("1.按添加的先后顺序排序 2.按年龄的大小排序");
break;
case 9:
System.out.println("批量增加");
while(!exit)
{
//for(int k = 0;k < 5;k++)
//{
//if(sc.next.equals("1")||sc.next.equals("2")){}
//if(k == 5)
//{
//System.out.println("鉴于你无语的操作，本程序退出！");
case 3:
me.add();
System.out.print("输入 7 保存，否则你的增加信息不被写入到文件");
//me.write();
break;
case 4:
int age6 = Integer.parseInt(str3);
me.checkage(age6);
}catch(NumberFormatException e)
{
System.out.println("请输入密码：");
String password = sc.next();
if(name.equals("admin")&&password.equals("8888"))
{
boolean login = true;
//exit = true;
//break;
//}
try
{
String s1 = sc.next();
int choice = Integer.parseInt(s1);
switch(choice)
{
String job6 = sc.next();
me.checkjob(job6);
break;
default:
System.out.println("请输入正确的数字（1,2,3,4）");
case 3:
System.out.println("请输入要查询的年龄");
try
{
String str3 = sc.next();