[Java]基础入门-Day 4

[Java]基础入门-Day4

学习使用工具

黑马2023新版Java视频教程 https://www.bilibili.com/video/BV1Fv4y1q7ZH?p=8&vd_source=03da0cdb826d78c565cd22a83928f4c2

Java程序员进阶之路 https://tobebetterjavaer.com/overview/java-can-do-what.html

零、前言

内容：实现一个简单的学生信息管理系统，具有增加学生、查询学生、删除学生、修改学生信息、输出当前学生信息等功能。

目的：熟悉Java基本操作与语法。

一、Student类

public class Student {
    private String id;
    private String name;
    private int age;
    private String date;
    Student(String id, String name, int age, String date){
        this.id = id;
        this.name = name;
        this.age = age;
        this.date = date;
    }

    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 String getDate() {
        return date;
    }

    public void setDate(String date) {
        this.date = date;
    }

    public int getAge() {
        return age;
    }

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

二、StudentTable类

import java.util.Date;
import java.util.Iterator;
import java.util.LinkedList;

public class StudentTable {
    private LinkedList<Student> list;

    StudentTable(){
        list = new LinkedList<Student>();
    }

    public boolean addStudent(String ID, String name, int age, String date){
        for (Student stu: list) {
            if (stu.getId().equals(ID)) {
                return false; // 代表ID重复，添加失败
            }
        }
        Student stu = new Student(ID, name, age, date);
        list.add(stu);
        return true; // 添加成功
    }

    public LinkedList<Student> getList() {
        return list;
    }

    public boolean removeStudent(String ID){
        Iterator<Student> stu = list.iterator();
        while (stu.hasNext()) {
            Student temp = stu.next();
            if (ID.equals(temp.getId())) {
                stu.remove();
                return true;
            }
        }
        return false;
    }

    public Student findStudent(String ID){
        Iterator<Student> stu = list.iterator();
        while (stu.hasNext()) {
            Student temp = stu.next();
            if (ID.equals(temp.getId())) {
                return temp;
            }
        }
        return null;
    }

    public boolean changeStudentName(String ID, String name){
        Iterator<Student> stu = list.iterator();
        while (stu.hasNext()) {
            Student temp = stu.next();
            if (ID.equals(temp.getId())) {
                temp.setName(name);
                return true;
            }
        }
        return false;
    }

    public boolean changeStudentAge(String ID, int age){
        Iterator<Student> stu = list.iterator();
        while (stu.hasNext()) {
            Student temp = stu.next();
            if (ID.equals(temp.getId())) {
                temp.setAge(age);
                return true;
            }
        }
        return false;
    }

    public boolean changeStudentDate(String ID, String date){
        Iterator<Student> stu = list.iterator();
        while (stu.hasNext()) {
            Student temp = stu.next();
            if (ID.equals(temp.getId())) {
                temp.setDate(date);
                return true;
            }
        }
        return false;
    }
}

三、Main类

import java.util.LinkedList;
import java.util.Scanner;

public class Main {
    private static StudentTable studentTable;
    public static void addStudent(){
        Scanner sc = new Scanner(System.in);
        System.out.println("--------添加学生--------");
        System.out.println("请输入学生学号：");
        String ID = sc.nextLine();
        System.out.println("请输入学生名称：");
        String name = sc.nextLine();
        System.out.println("请输入学生年龄：");
        int age = sc.nextInt();
        System.out.println("请输入学生出生日期：");
        String date = sc.next();
        boolean flag = studentTable.addStudent(ID, name, age, date);
        while(!flag){
            System.out.println("学号已经存在，请重新输入学号：");
            ID = sc.nextLine();
            flag = studentTable.addStudent(ID, name, age, date);
        }
        System.out.println("学号为："+ID+"的学生信息添加成功！");
    }
    public static void findStudent(){
        Scanner sc = new Scanner(System.in);
        System.out.println("--------查找学生--------");
        System.out.println("请输入学生学号：");
        String ID = sc.nextLine();
        Student stu = studentTable.findStudent(ID);
        if(stu == null){
            System.out.println("未查找到对应学生。");
        }else{
            System.out.println("该学生的信息如下：");
            System.out.println("学号："+stu.getId()+",姓名："+stu.getName()+",年龄："+stu.getAge()+",生日："+stu.getDate());
        }
    }
    public static void removeStudent(){
        Scanner sc = new Scanner(System.in);
        System.out.println("--------删除学生--------");
        System.out.println("请输入学生学号：");
        String ID = sc.nextLine();
        if(studentTable.removeStudent(ID)){
            System.out.println("删除成功！");
        }else{
            System.out.println("未查找到对应学生，删除失败！");
        }
    }

    public static int ChangeStudent(){
        Scanner sc = new Scanner(System.in);
        System.out.println("--------修改学生信息--------");
        System.out.println("请输入学生学号：");
        String ID = sc.nextLine();
        System.out.println("请选择修改部分：");
        System.out.println("1.姓名：");
        System.out.println("2.年龄：");
        System.out.println("3.生日：");
        while(true){
            int choice = sc.nextInt();
            switch(choice){
                case 1:
                    System.out.println("请输入姓名：");
                    String name = sc.nextLine();
                    if(studentTable.changeStudentName(ID,name)){
                        System.out.println("修改成功！");
                    }else{
                        System.out.println("未查找到对应学生，修改失败！");
                    }
                    return 0;
                case 2:
                    System.out.println("请输入年龄：");
                    int age = sc.nextInt();
                    if(studentTable.changeStudentAge(ID,age)){
                        System.out.println("修改成功！");
                    }else{
                        System.out.println("未查找到对应学生，修改失败！");
                    }
                    return 0;
                case 3:
                    System.out.println("请输入出生日期：");
                    String date = sc.nextLine();
                    if(studentTable.changeStudentDate(ID,date)){
                        System.out.println("修改成功！");
                    }else{
                        System.out.println("未查找到对应学生，修改失败！");
                    }
                    return 0;
                default:
                    System.out.println("输入错误，请重新输入。");
                    break;
            }
        }
    }

    public static void PrintStudent(){
        System.out.println("--------当前学生信息--------");
        System.out.printf("%5s%5s%10s","姓名","年龄","出生日期");
        System.out.println();
        LinkedList<Student> stu = studentTable.getList();
        for(Student temp:stu){
            System.out.printf("%5s%6d%16s",temp.getName(),temp.getAge(),temp.getDate());
            System.out.println();
        }
    }
    public static void main(String[] args) {
        studentTable = new StudentTable();
        Scanner sc = new Scanner(System.in);
        System.out.println("欢迎使用学生管理系统！请选择您的操作：");
        while(true){
            System.out.println("1.添加学生");
            System.out.println("2.查询学生");
            System.out.println("3.删除学生");
            System.out.println("4.修改学生信息");
            System.out.println("5.输出当前所有学生信息");
            System.out.println("6.退出程序");

            int choice = sc.nextInt();

            switch(choice) {
                case 1:
                    addStudent();
                    break;
                case 2:
                    findStudent();
                    break;
                case 3:
                    removeStudent();
                    break;
                case 4:
                    ChangeStudent();
                    break;
                case 5:
                    PrintStudent();
                    break;
                case 6:
                    System.out.println("谢谢您的使用，再见！");
                    System.exit(0);
                default:
                    System.out.println("输入错误，请重新输入。");
                    break;
            }
        }
    }
}