用Java做一个班级成绩管理系统实现对班级成绩的录入、显示、增加、删除、修改、统计等操作的管理的代码

好的，以下是一个简单的班级成绩管理系统的 Java 代码实现，包括增、删、改、查、统计等操作：

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

public class GradeManagementSystem {
    private static List<Student> students = new ArrayList<>();
    private static Scanner scanner = new Scanner(System.in);

    public static void main(String[] args) {
        while (true) {
            System.out.println("请选择操作：");
            System.out.println("1. 查看成绩");
            System.out.println("2. 录入成绩");
            System.out.println("3. 修改成绩");
            System.out.println("4. 删除成绩");
            System.out.println("5. 统计成绩");
            System.out.println("0. 退出系统");

            int choice = scanner.nextInt();
            switch (choice) {
                case 0:
                    System.out.println("退出系统");
                    System.exit(0);
                case 1:
                    displayGrades();
                    break;
                case 2:
                    addGrade();
                    break;
                case 3:
                    updateGrade();
                    break;
                case 4:
                    deleteGrade();
                    break;
                case 5:
                    statistics();
                    break;
                default:
                    System.out.println("无效操作");
            }
        }
    }

    private static void displayGrades() {
        if (students.isEmpty()) {
            System.out.println("暂无成绩信息");
            return;
        }
        System.out.println("学号\t姓名\t语文\t数学\t英语");
        for (Student student : students) {
            System.out.println(student);
        }
    }

    private static void addGrade() {
        System.out.println("请输入学生信息（学号、姓名、语文成绩、数学成绩、英语成绩，用空格隔开）：");
        int id = scanner.nextInt();
        String name = scanner.next();
        int chinese = scanner.nextInt();
        int math = scanner.nextInt();
        int english = scanner.nextInt();
        Student student = new Student(id, name, chinese, math, english);
        students.add(student);
        System.out.println("添加成功");
    }

    private static void updateGrade() {
        System.out.println("请输入要修改的学生学号：");
        int id = scanner.nextInt();
        Student student = findStudent(id);
        if (student == null) {
            System.out.println("未找到该学生");
            return;
        }
        System.out.println("请输入修改后的成绩（语文、数学、英语，用空格隔开）：");
        int chinese = scanner.nextInt();
        int math = scanner.nextInt();
        int english = scanner.nextInt();
        student.setChinese(chinese);
        student.setMath(math);
        student.setEnglish(english);
        System.out.println("修改成功");
    }

    private static void deleteGrade() {
        System.out.println("请输入要删除的学生学号：");
        int id = scanner.nextInt();
        Student student = findStudent(id);
        if (student == null) {
            System.out.println("未找到该学生");
            return;
        }
        students.remove(student);
        System.out.println("删除成功");
    }

    private static void statistics() {
        if (students.isEmpty()) {
            System.out.println("暂无成绩信息");
            return;
        }
        int sumChinese = 0;
        int sumMath = 0;
        int sumEnglish = 0;
        double avgChinese = 0.0;
        double avgMath = 0.0;
        double avgEnglish = 0.0;
        for (Student student : students) {
            sumChinese += student.getChinese();
            sumMath += student.getMath();
            sumEnglish += student.getEnglish();
        }
        int size = students.size();
        avgChinese = sumChinese / (double)size;
        avgMath = sumMath / (double)size;
        avgEnglish = sumEnglish / (double)size;
        System.out.println("语文平均分：" + avgChinese);
        System.out.println("数学平均分：" + avgMath);
        System.out.println("英语平均分：" + avgEnglish);
    }

    private static Student findStudent(int id) {
        for (Student student : students) {
            if (student.getId() == id) {
                return student;
            }
        }
        return null;
    }
}

class Student {
    private int id;
    private String name;
    private int chinese;
    private int math;
    private int english;

    public Student(int id, String name, int chinese, int math, int english) {
        this.id = id;
        this.name = name;
        this.chinese = chinese;
        this.math = math;
        this.english = english;
    }

    public int getId() {
        return id;
    }

    public String getName() {
        return name;
    }

    public int getChinese() {
        return chinese;
    }

    public void setChinese(int chinese) {
        this.chinese = chinese;
    }

    public int getMath() {
        return math;
    }

    public void setMath(int math) {
        this.math = math;
    }

    public int getEnglish() {
        return english;
    }

    public void setEnglish(int english) {
        this.english = english;
    }

    @Override
    public String toString() {
        return id + "\t" + name + "\t" + chinese + "\t" + math + "\t" + english;
    }
}

以上代码实现了一个简单的班级成绩管理系统，可以通过命令行交互进行操作。