package com.blackhouse.day01;


//这里是创建了一个学生类的信息，没什么好说的，太简单了
public class Student {
    String name;
    String studentId;
    String sex;
    double grade;

    Student(){

    }
    Student(String name,String studentId,String sex,double grade){
        this.name = name;
        this.studentId = studentId;
        this.sex = sex;
        this.grade = grade;
    }

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


    public void setStudentId(String studentId){
        this.studentId = studentId;
    }
    public String getStudentId(){
        return studentId;
    }


    public void setSex(String sex){
        this.sex = sex;
    }
    public String getSex(){
        return sex;
    }


    public void setGrade(double grade){
        this.grade = grade;
    }
    public  double getGrade(){
        return grade;
    }
}

package com.blackhouse.day01;

import java.util.*;

public class Manager {


    static List<Student> StudentList = new LinkedList<Student>();
    public static void main(String[] args){


        select(StudentList);
    }

    private static void select(List<Student> StudentList) {
        System.out.println("********************************************");
        System.out.println("*1：增加学生                                  ");
        System.out.println("*2：删除学生                                  ");
        System.out.println("*3：修改学生                                  ");
        System.out.println("*4：查询成绩                                  ");
        System.out.println("********************************************");


        System.out.println("你要选择的操作是：");
        Scanner sc = new Scanner(System.in);
        int chioce = sc.nextInt();
        switch(chioce){
            //增加学生
            case 1:
                System.out.println("请输入学生的姓名:");
                Scanner Sname = new Scanner(System.in);
                String name = Sname.nextLine();


                System.out.println("请输入学生性别:");
                Scanner Ssex = new Scanner(System.in);
                String sex = Ssex.nextLine();


                System.out.println("请输入学生的学号：");
                Scanner SId = new Scanner(System.in);
                String studentId = SId.nextLine();


                System.out.println("请输入学生的成绩");
                Scanner Sgrade = new Scanner(System.in);
                double grade = Sgrade.nextDouble();

                StudentList.add(new Student(name,studentId,sex,grade));
                System.out.println("添加成功！！！！！！");
                select(StudentList);
                break;

                //删除学生信息
            case 2:
                System.out.println("请告诉我你要删除的学生的学号：");
                Scanner Sid = new Scanner(System.in);
                String SstudentId = Sid.nextLine();
                boolean isfindDelete = false;
                for(int i = 0; i < StudentList.size(); i++){
                    if(SstudentId.equals(StudentList.get(i).getStudentId())){
                        System.out.println("发现了该学生，正在删除。。。");
                        StudentList.remove(i);
                        System.out.println("删除成功！！！");
                        isfindDelete = true;
                    }
                }
                if(!isfindDelete){
                    System.out.println("抱歉，没有找到");
                }
                select(StudentList);
                break;




                //修改学生成绩
            case 3:
                System.out.println("请告诉我你要修改的学号：");
                Scanner GId = new Scanner(System.in);
                String GstusentId = GId.nextLine();
                boolean isfindChande = false;
                for(int j = 0;j < StudentList.size();j++) {
                    if(GstusentId.equals(StudentList.get(j).getStudentId())){
                        System.out.println("发现了该学生，正在修改。。。");
                        System.out.println("原来学生的成绩为：" +StudentList.get(j).getGrade());
                        System.out.println("请输入修改后学生的成绩：");
                        Scanner Ggrade = new Scanner(System.in);
                        double grade2 = Ggrade.nextDouble();
                        StudentList.get(j).setGrade(grade2);
                        System.out.println("修改成功");
                        isfindChande = true;

                    }else{}

                }
                if(!isfindChande){
                    System.out.println("抱歉没有找到");
                }
                select(StudentList);
                break;
                //查看学生的成绩
            case 4:
                System.out.println("请输入你要查询的学生的学号");
                Scanner CId = new Scanner(System.in);
                String CStudentId = CId.nextLine();
                boolean isfindData = false;

                for(int i = 0;i < StudentList.size();i++){
                    if(CStudentId.equals(StudentList.get(i).getStudentId())){
                        System.out.println("名字:"+ StudentList.get(i).getName());
                        System.out.println("性别:"+StudentList.get(i).getSex());
                        System.out.println("学号:"+StudentList.get(i).getStudentId());
                        System.out.println("成绩:"+StudentList.get(i).getGrade());
                        isfindData = true;
                    }
                }
                if(!isfindData){
                    System.out.println("没有此学生");
                }
                select(StudentList);
                break;
            default:
                System.out.println("输入错误，请重新输入：");
                break;

        }
    }
}