学生增删改查练习

package day11;

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

public class Test {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        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 查看学生");
            System.out.println("5 退出");
            System.out.println("请输入您的选择：");
            int choice = sc.nextInt();
            switch (choice) {
                case 1:
                    addStudent(list);
                    break;
                case 2:
                    deleteStudent(list);
                    break;
                case 3:
                    updateStudent(list);
                    break;
                case 4:
                    queryStudent(list);
                    break;
                case 5:
                    System.out.println("感谢您的使用");
                    break;
                default:
                    System.out.println("输入的数据有误！");
                    break;
            }
        }
    }

    private static void addStudent(ArrayList<Student> list) {
        Scanner sc = new Scanner(System.in);
        String sid;
        while (true) {
            System.out.println("请输入学号：");
            sid = sc.nextLine();
            int index = getIndex(list, sid);
            if (index == -1) {
                break;
            } else {
                System.out.println("学号已被占用");
            }
        }
        System.out.println("请输入姓名：");
        String name = sc.nextLine();
        System.out.println("请输入年龄：");
        String age = sc.nextLine();
        System.out.println("请输入生日：");
        String birthday = sc.nextLine();
        Student stu = new Student(sid, name, age, birthday);
        list.add(stu);
        System.out.println("添加学生成功");
    }

    private static void deleteStudent(ArrayList<Student> list) {
        Scanner sc = new Scanner(System.in);
        System.out.println("请输入要删除的学号");
        String delSid = sc.nextLine();
        int index = getIndex(list, delSid);
        if (index == -1) {
            System.out.println("该信息不存在，请重新输入");
        } else {
            list.remove(index);
            System.out.println("删除成功！");
        }
    }

    private static void updateStudent(ArrayList<Student> list) {
        Scanner sc = new Scanner(System.in);
        System.out.println("请输入你要修改的学号：");
        String updateSid = sc.nextLine();
        int index = getIndex(list, updateSid);
        if (index == -1) {
            System.out.println("输入的信息不存在，请重入");
        } else {
            System.out.println("请输入新的姓名：");
            String name = sc.nextLine();
            System.out.println("请输入新的年龄：");
            String age = sc.nextLine();
            System.out.println("请输入新的生日：");
            String birthday = sc.nextLine();
            Student stu = new Student(updateSid, name, age, birthday);
            list.set(index, stu);
            System.out.println("修改成功");
        }
    }

    private static int getIndex(ArrayList<Student> list, String sid) {
        int index = -1;
        for (int i = 0; i < list.size(); i++) {
            Student stu = list.get(i);
            if (sid.equals(stu.getSid())) {
                index = i;
            }
        }
        return index;
    }

    private static void queryStudent(ArrayList<Student> list) {
        if (list == null || list.size() == 0) {
            System.out.println("无此学生信息，请添加后重试");
        } else {
            System.out.println("学号		姓名		年龄		生日");
            for (int i = 0; i < list.size(); i++) {
                Student stu = list.get(i);
                System.out.println(stu.getSid() + "		" + stu.getName() + "	" + stu.getAge() + "		" + stu.getBirthday());
            }
        }
    }
}

执行结果1：

 执行结果2：

 执行结果3：

 执行结果：

 【Student.java】

package day11;

public class Student {
private String sid;
private String name;
private String age;
private String birthday;

    public Student(String sid, String name, String age, String birthday) {
        this.sid = sid;
        this.name = name;
        this.age = age;
        this.birthday = birthday;
    }

    public String getBirthday() {
        return birthday;
    }

    public void setBirthday(String birthday) {
        this.birthday = birthday;
    }

    public String getAge() {
        return age;
    }

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

    public String getName() {
        return name;
    }

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

    public String getSid() {
        return sid;
    }

    public void setSid(String sid) {
        this.sid = sid;
    }
}