package bean;

public class Student {

private int id;
private String name;
private int age;

public int getId() {
    return id;
}
public void setId(int id) {
    this.id = id;
}
public String getName() {
    return name;
}
public void setName(String name) {
    this.name = name;
}
public int getAge() {
    return age;
}
public void setAge(int age) {
    if(age>0 && age<=150){
        this.age = age;
    }else{
        System.out.println("输入的年龄有误！");
    }
}
public Student() {
    super();
}
public Student(int id, String name, int age) {
    super();
    setId(id);
    setName(name);
    setAge(age);
}

@Override
public String toString() {
    return "学生 [学号 =" + id + ", 姓名 =" + name + ", 年龄 =" + age + "]";
}

@Override
public int hashCode() {
    final int prime = 31;
    int result = 1;
    result = prime * result + id;
    return result;
}

@Override
public boolean equals(Object obj) {
    if (this == obj)
        return true;
    if (obj == null)
        return false;
    if (getClass() != obj.getClass())
        return false;
    Student other = (Student) obj;
    if (id != other.id)
        return false;
    return true;
}   

}

package main;

import java.util.Scanner;

import util.StudentManager;

public class Main {

static Scanner input = new Scanner(System.in);

public static void main(String[] args) {

    System.out.println("************************************************");
    System.out.println("********\t欢迎来到学生管理系统\t********");
    System.out.println("********\t请根据提示进行操作\t********");
    System.out.println("************************************************");

    // 提示用户输入管理员账号密码
    System.out.println("请输入管理员账号：");
    String username = input.nextLine();
    System.out.println("请输入管理员密码：");
    String password = input.nextLine();

    // 判断输入的用户名密码是否正确
    if ("admin".matches(username) && "123456".matches(password)) {

        System.out.println("恭喜你，登陆成功:");

        out:while (true) {
            // 提示用户输入数字，选择功能
            System.out.println("请根据提示选择功能:");
            System.out.println("\t1、 添加学生：");
            System.out.println("\t2、 删除学生：");
            System.out.println("\t3、 查找学生：");
            System.out.println("\t4、 查看所有学生：");
            System.out.println("\t5、 退出系统");

            int num = Integer.parseInt(input.nextLine());

            switch (num) {
            case 1:
                StudentManager.add();
                break;
            case 2:
                StudentManager.del();
                break;
            case 3:
                StudentManager.search();
                break;
            case 4:
                StudentManager.searchAll();
                break;
            case 5:
                System.out.println("\t退出系统");
                break out;
            default:
                System.out.println("\t输入错误，请重新输入！");
                break;
            }
        }
    } else {
        System.out.println("********\t对不起输入错误，大帅比，懵逼了吧\t********");
    }

}

}

package util;

import java.util.ArrayList;
import java.util.Scanner;

import bean.Student;

public class StudentManager {

static Scanner input = new Scanner(System.in);

static ArrayList<Student> students = new ArrayList<>();

public static void add(){
    
    add:while (true) {

// 提示语句
System.out.println("请根据提示输入学生信息，输入 0 退出添加学生");

        System.out.println("请输入学生的学号：");
        int id = Integer.parseInt(input.nextLine());
        if(0 == id){
            break add;
        }
        System.out.println("请输入学生的姓名：");
        String name = input.nextLine();
        System.out.println("请输入学生的年龄：");
        int age = Integer.parseInt(input.nextLine());
        
        students.add(new Student(id,name,age));
        
    }
}

public static void del(){
    add:while (true) {

// 提示语句
System.out.println("请根据提示输入学号删除学生，输入 0 退出删除学生");

        System.out.println("请输入学生的学号：");
        int id = Integer.parseInt(input.nextLine());
        if(0 == id){
            break add;
        }
        Student s = new Student();
        s.setId(id);
        students.remove(s);
        
    }
}

public static void search(){
    add:while (true) {

// 提示语句
System.out.println("请根据提示输入学号删除学生，输入 0 退出查找学生");

        System.out.println("请输入学生的学号：");
        int id = Integer.parseInt(input.nextLine());
        if(0 == id){
            break add;
        }
        Student s = new Student();
        s.setId(id);
        if(students.contains(s)){
            System.out.println(students.get(students.indexOf(s)));
        }else{
            System.out.println("抱歉，系统中没有这个学生！");
        }
        
        
    }
}

public static void searchAll(){
    for(int i=0; i<students.size();i++){
        System.out.println(students.get(i));
    }
}

}