第5节学生管理系统升级版

package com.itheima_01;
/*
* 学生类
* */

public class Student {
    private String sid;//学号
    private String name;//姓名
    private String age;//年龄
    private String address;//居住地

    //快捷键：Alt+InsScrlk 根据自己的需要进行选择
    //无参构造
    public Student() {
    }

    //带参构造
    public Student(String sid, String name, String age, String address) {
        this.sid = sid;
        this.name = name;
        this.age = age;
        this.address = address;
    }

    //get/set方法
    public String getSid() {
        return sid;
    }

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

    public String getName() {
        return name;
    }

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

    public String getAge() {
        return age;
    }

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

    public String getAddress() {
        return address;
    }

    public void setAddress(String address) {
        this.address = address;
    }
}

package com.itheima_01;
/*
 * 学生管理系统
 * */

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

public class StudentDemo {
    public static void main(String[] args) {
        //定义一个集合，用于存储学生数据
        ArrayList<Student> array = new ArrayList<Student>();

        while (true) {
            //用输入出语句完成主界面的编写
            System.out.println("\n----------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 查看所有学生");
            System.out.println("5 退出系统");
            System.out.print("\n请输入你的选择：");

            //用Scanner实现键盘录入
            Scanner sc = new Scanner(System.in);
            String line = sc.nextLine();

            //用Switch语句完成操作
            switch (line) {
                case "1":
                    System.out.println("*添加学生*");
                    addStudent(array);
                    break;
                case "2":
                    System.out.println("*删除学生*");
                    delStudent(array);
                    break;
                case "3":
                    System.out.println("*修改学生*");
                    updateStudent(array);
                    break;
                case "4":
                    System.out.println("*查看所有学生*");
                    finaddStudent(array);
                    break;
                case "5":
                    System.out.println("**谢谢使用，欢迎下次光临**");
                    System.exit(0);
            }
        }
    }

    //创建添加学生方法
    public static void addStudent(ArrayList<Student> array) {
        Scanner sc = new Scanner(System.in);
        String sid;
        while(true){
            System.out.println("请输入学号：");
            sid = sc.nextLine();
            boolean flag = isUsed(array, sid);
            if(flag==true){
                System.out.println("该学已被占用，请重新录入");
            }else{
                break;
            }
        }
        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("请输入居住地：");
        String address = sc.nextLine();

        Student s = new Student();
        s.setSid(sid);
        s.setName(name);
        s.setAge(age);
        s.setAddress(address);

        array.add(s);
        System.out.println("添加学生成功");


    }

    //定义一个方法判断学号是否存在
    public static boolean isUsed(ArrayList<Student> array, String sid) {
        boolean flag = false;
        for (int i = 0; i < array.size(); i++) {
            Student s=array.get(i);
            if(sid.equals(s.getSid())){
                flag=true;
                break;
            }
        }
        return flag;
    }

    //查看所有学生信息方法
    public static void finaddStudent(ArrayList<Student> array) {
        if (array.size() == 0) {
            System.out.println("无学生信息可查，请先添加学生");
        } else {
            System.out.println("学号\t\t\t姓名\t\t年龄\t\t居住地");
            for (int i = 0; i < array.size(); i++) {
                Student s = array.get(i);
                System.out.println(s.getSid() + "\t" + s.getName() + "\t" + s.getAge() + "岁\t" + s.getAddress());
            }

        }
    }

    //删除学生方法
    public static void delStudent(ArrayList<Student> array) {
        Scanner sc = new Scanner(System.in);
        System.out.println("请输入要删除学生的学号：");
        String line = sc.nextLine();
        for (int i = 0; i < array.size(); i++) {
            Student s = array.get(i);
            if (line.equals(s.getSid())) {
                array.remove(i);
                System.out.println("删除学生成功");
                break;
            } else {
                System.out.println("无此学生信息，请检查学号是否输入正确");
            }
        }
    }

    //修改学生方法
    public static void updateStudent(ArrayList<Student> array) {
        Scanner sc = new Scanner(System.in);
        System.out.println("请输入你要修改信息的学生学号：");
        String line = sc.nextLine();
        for (int i = 0; i < array.size(); i++) {
            Student s = array.get(i);
            if (line.equals(s.getSid())) {
                System.out.println("请输入学生姓名：");
                String name = sc.nextLine();
                System.out.println("请输入学生年龄：");
                String age = sc.nextLine();
                System.out.println("请输入学生居住地：");
                String address = sc.nextLine();
                s.setName(name);
                s.setAge(age);
                s.setAddress(address);
                array.set(i, s);
                System.out.println("修改成功");
                break;
            } else {
                System.out.println("无此学生信息，请检查学号是否输入正确");
            }
        }
    }
}