第五周

//创建学生类
public class Student {
    private String name;
    private int age;
    private String id;
    private String address;

    public Student() {
    }

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

    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 getId() {
        return id;
    }

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


    public String getAddress() {
        return address;
    }


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

}

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

public class StudentSystem {
    public static void main(String[] args) {
        ArrayList<Student> students = new ArrayList<Student>();

        loop: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("请输入你的选择:");
            Scanner sc = new Scanner(System.in);
            String input = sc.next();
            switch (input) {
                case "1"-> addStudent(students);
                case "2"-> deleteStudent(students);
                case "3"-> updateStudent(students);
                case "4"-> queryStudent(students);
                case "5"-> {
                    System.out.println("退出");
                    break loop;
                }
                default -> System.out.println("没有这个选项");
            }
        }
    }
//添加学生信息
    public static void addStudent(ArrayList<Student> students) {
        Student student = new Student();
        Scanner sc = new Scanner(System.in);
        String id = null;
        while (true) {
            System.out.println("请输入学生Id");
            id = sc.next();
            boolean flag = contain(students, id);
            if (flag) {
                System.out.println("Id存在重新录入");
            }
            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);
        students.add(student);
        System.out.println("学生信息添加成功");
    }
//删除学生信息
    public static void deleteStudent(ArrayList<Student> students) {
        Scanner sc = new Scanner(System.in);
        String id = null;
        System.out.println("请输入删除的Id");
        id = sc.next();
        int index = index(students, id);
        if (index >= 0) {
            students.remove(index);
            System.out.println("Id删除成功");
        }
        else {
            System.out.println("Id不存在，删除失败");
        }
    }
//修改学生信息
    public static void updateStudent(ArrayList<Student> students) {
        Scanner sc = new Scanner(System.in);
        String id = null;
        System.out.println("请输入要修改的Id");
        id = sc.next();
        int index = index(students, id);
        if (index >= 0) {
            Student student = students.get(index);
            System.out.println("请输入要修改的学生姓名");
            String name = sc.next();
            System.out.println("请输入要修改的学生年龄");
            int age = sc.nextInt();
            System.out.println("请输入要修改的学生家庭住址");
            String address = sc.next();
            student.setName(name);
            student.setAge(age);
            student.setAddress(address);
            System.out.println("学生信息修改成功");
        }
        else {
            System.out.println("要修改的Id不存在");
        }
    }
//查询学生信息
    public static void queryStudent(ArrayList<Student> students) {
        if (students.size() == 0) {
            System.out.println("无学生数据，请添加后查看");
            return;
        }
        System.out.println("id\t\t\t姓名\t\t年龄\t\t家庭住址");
        for (int i = 0; i < students.size(); i++) {
            Student student = students.get(i);
            System.out.println(student.getId() + "\t" + student.getName() + "\t" + student.getAge()+ "\t" + student.getAddress());
        }
    }
    //判断Id是否存在
    public static boolean contain (ArrayList<Student> students, String id){
        return index(students, id) >= 0;
    }
    //获得Id索引
    public static int index(ArrayList<Student> students, String id) {
        for (int i = 0; i < students.size(); i++) {
            Student student = students.get(i);
            String studentId = student.getId();
            if(Objects.equals(studentId, id)) {
                return i;
            }
        }
        return -1;
    }
}

public abstract class Person {
    private String name;
    private int age;

    public Person(String name, int age) {
        this.name = name;
        this.age = age;
    }

    public Person() {
    }

    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 abstract class Sporter extends Person {
    public Sporter() {
    }

    public Sporter(String name, int age) {
        super(name, age);
    }

    public abstract void study();
}

public interface English {
    public abstract void speakEnglish();
}

public class pingpongSporter extends Sporter implements English {
    public pingpongSporter() {}

    public pingpongSporter(String name, int age) {
        super(name, age);
    }
    @Override
    public void study(){
        System.out.println("乒乓球运动员在练习乒乓球");
    }
    @Override
    public void speakEnglish(){
        System.out.println("乒乓球运动员在说英语");
    }
}

public class Test {
    public static void main(String[] args) {
        pingpongSporter pps = new pingpongSporter("刘诗雯",23);
        System.out.println(pps.getName()+","+pps.getAge());
        pps.study();
        pps.speakEnglish();

    }
}