java——学生信息管理系统

        终于，幼儿园版的学生信息管理系统来了，尽管是幼儿园版的，已经不能再简单了，但依旧存在一些问题，真是不试试都不知道自己有多辣鸡

student类

public class Student {
    private int age;
    private String name;
    private String id;

    public Student(){}

    public String getId() {
        return id;
    }
    public int getAge() {
        return age;
    }
    public String getName(){
        return name;
    }

    public void setId(String id) {
        this.id = id;

    }

    public void setAge(int age){
        this.age=age;
    }
    public void setName(String name){
        this.name=name;
    }
    
}

测试类

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

public class test18 {

    public static void print() {
        System.out.println("1：添加学生信息");
        System.out.println("2：删除学生信息");
        System.out.println("3：修改学生信息");
        System.out.println("4：查询学生信息");
        System.out.println("5：退出");
    }

    public static void add(ArrayList list) {
        Student student = new Student();
        System.out.println("请输入学号：");
        Scanner sc1 = new Scanner(System.in);
        String id = sc1.nextLine();
        if(list.size()==0){
            System.out.println("请输入名字：");
            Scanner sc2 = new Scanner(System.in);
            String name = sc2.nextLine();
            System.out.println("请输入年龄：");
            Scanner sc3 = new Scanner(System.in);
            int age = sc3.nextInt();
            student.setId(id);
            student.setName(name);
            student.setAge(age);
            list.add(student);
            System.out.println("添加成功！！！");
            return;
        }else{
            for(int j=0;j list) {
        System.out.println("请输入学号进行删除：");
        Scanner sc = new Scanner(System.in);
        String s = sc.nextLine();
        for (int i = 0; i < list.size(); i++) {
            if (list.get(i).getId().equals(s)) {
                list.remove(i);
                System.out.println("删除成功！！！");
                break;
            }
            if (i == list.size() - 1 && !list.get(i).getId().equals(s)) {
                System.out.println("查无此人！！！");
            }
        }
    }

    public static void update(ArrayList list) {
        System.out.println("请输入学号进行修改：");
        Student student = new Student();
        Scanner sc1 = new Scanner(System.in);
        String s1 = sc1.nextLine();
        for (int i = 0; i < list.size(); i++) {
            if (list.get(i).getId().equals(s1)) {
                System.out.println("请输入新名字：");
                Scanner sc2 = new Scanner(System.in);
                String s2 = sc2.nextLine();
                System.out.println("请输入新年龄：");
                Scanner sc3 = new Scanner(System.in);
                int s3 = sc3.nextInt();
                student.setId(s1);
                student.setName(s2);
                student.setAge(s3);
                list.set(i, student);
                System.out.println("更新成功！！！");
                break;
            }
            if (i == list.size() - 1 && !list.get(i).getId().equals(s1)) {
                System.out.println("查无此人！！！");
            }
        }
    }

    public static void select(ArrayList list) {
        System.out.println("请输入姓名查询：");
        Scanner sc1 = new Scanner(System.in);
        String s1 = sc1.nextLine();
        for (int i = 0; i < list.size(); i++) {
            Student stu = list.get(i);
            if (stu.getName().contains(s1)) {
                System.out.println("###############");
                String str = "学号：" + list.get(i).getId() + "n" + "姓名：" + list.get(i).getName() + "n" + "年龄：" + list.get(i).getAge() + "n";
                System.out.println(str);
                System.out.println("###############");
            }else{
                System.out.println("查无此人！！！");
            }
        }
    }

    public static void main(String[] args) {
        System.out.println("学生信息管理系统");
        ArrayList list = new ArrayList();
        for (int x = 0; ; x++) {
            print();
            System.out.println("请输入操作：");
            Scanner sc = new Scanner(System.in);
            int i = sc.nextInt();

            switch (i) {
                case 1:
                    add(list);
                    break;
                case 2:
                    delect(list);
                    break;
                case 3:
                    update(list);
                    break;
                case 4:
                    select(list);
                    break;
                case 5:
                    return;
                default:
                    System.out.println("输入错误！！！");
            }
        }
    }
}

为了更简单一点，防止过于复杂，方便我找问题，有些情况我没有考虑进去，所以有很多不足，并且还有许多需要改进的地方，以我目前的水平，这已经还算可以了。