最近在学java，看的黑马程序员的视频， 刚学到一个项目，学生管理系统，自己跟着用代码实现了一下。下面是我的代码。

javabean类
Student.java

public class Student {private String id;private String name;private int age;private String address;public Student() {}public Student(String id, String name, int age, String address) {this.id = id;this.name = name;this.age = age;this.address = address;}public String getId() {return id;}public void setId(String 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) {this.age = age;}public String getAddress() {return address;}public void setAddress(String address) {this.address = address;}
}

测试类
Main.java

import java.util.ArrayList;
import java.util.Scanner;public class Main {public static void main(String[] args) {ArrayList<Student> list = new ArrayList<>();while (true) {System.out.println("------------欢迎来到学生管理系统-----------");System.out.println("1:添加学生");System.out.println("2:删除学生");System.out.println("3:修改学生");System.out.println("4:查询学生");System.out.println("5:退出");System.out.println("请输入您的选择");Scanner sc = new Scanner(System.in);String input = sc.next();switch (input) {case "1" -> addStudent(list);case "2" -> deleteStudent(list);case "3" -> modifyStudent(list);case "4" -> searchStudent(list);case "5" -> {System.out.println("程序退出");System.exit(0);}default -> System.out.println("输入错误，请重新输入");}}}public static void addStudent(ArrayList<Student> list) {System.out.println("添加学生");Scanner sc = new Scanner(System.in);Student student = new Student();String id;while (true) {System.out.println("请输入学生id");id = sc.next();if (!isOnlyId(list, id)) {System.out.println("id重复，请重新输入");} else {student.setId(id);break;}}System.out.println("请输入学生姓名");String name = sc.next();student.setName(name);System.out.println("请输入学生年龄");int age = sc.nextInt();student.setAge(age);System.out.println("请输入学生家庭住址");String address = sc.next();student.setAddress(address);list.add(student);System.out.println("添加成功");}public static void deleteStudent(ArrayList<Student> list) {System.out.println("删除学生");Scanner sc = new Scanner(System.in);System.out.println("请输入要删除的学生id");String id = sc.next();for (int i = 0; i < list.size(); i++) {if (list.get(i).getId().equals(id)) {list.remove(i);System.out.println("删除成功");return;}}System.out.println("id不存在，删除失败");}public static void modifyStudent(ArrayList<Student> list) {System.out.println("修改学生");Scanner sc = new Scanner(System.in);System.out.println("请输入要修改学生的id");String id = sc.next();for (int i = 0; i < list.size(); i++) {if (list.get(i).getId().equals(id)) {System.out.println("请输入学生姓名");String name = sc.next();list.get(i).setName(name);System.out.println("请输入学生年龄");int age = sc.nextInt();list.get(i).setAge(age);System.out.println("请输入学生家庭住址");String address = sc.next();list.get(i).setAddress(address);System.out.println("学生信息修改成功");return;}}System.out.println("id不存在，修改失败");}public static void searchStudent(ArrayList<Student> list) {System.out.println("查询学生");if (list.isEmpty()) {System.out.println("当前无学生信息，请添加后再查询");return;}System.out.println("id\t" + "姓名\t" + "年龄\t" + "家庭住址");for (int i = 0; i < list.size(); i++) {System.out.println(list.get(i).getId() + '\t' + list.get(i).getName() + '\t' + list.get(i).getAge() + '\t' + list.get(i).getAddress());}}public static boolean isOnlyId(ArrayList<Student> list, String id) {for (int i = 0; i < list.size(); i++) {if (list.get(i).getId().equals(id)) {return false;}}return true;}
}

效果图