用java和mysql写一个学生成绩管理系统

好的，下面是一个基本的学生成绩管理系统的设计：

## 数据库设计

### 学生表

| 字段名 | 类型 | 描述 | 是否为主键 |
| ------ | ------- | ---------- | ---------- |
| id | int | 学生编号 | 是 |
| name | varchar | 学生姓名 | 否 |
| gender | varchar | 学生性别 | 否 |
| age | int | 学生年龄 | 否 |
| class | varchar | 学生班级 | 否 |

### 课程表

| 字段名 | 类型 | 描述 | 是否为主键 |
| ------ | ------- | ---------- | ---------- |
| id | int | 课程编号 | 是 |
| name | varchar | 课程名称 | 否 |

### 成绩表

| 字段名 | 类型 | 描述 | 是否为主键 |
| --------- | ------- | ---------- | ---------- |
| id | int | 成绩编号 | 是 |
| studentId | int | 学生编号 | 否 |
| courseId | int | 课程编号 | 否 |
| score | float | 成绩分数 | 否 |
| examDate | date | 考试日期 | 否 |
| remark | varchar | 成绩备注 | 否 |

## Java代码实现

### 学生类

public class Student {
    private int id;
    private String name;
    private String gender;
    private int age;
    private String className;

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

    // getter and setter methods
}

### 课程类

public class Course {
    private int id;
    private String name;

    public Course(int id, String name) {
        this.id = id;
        this.name = name;
    }

    // getter and setter methods
}

### 成绩类

public class Score {
    private int id;
    private int studentId;
    private int courseId;
    private float score;
    private Date examDate;
    private String remark;

    public Score(int id, int studentId, int courseId, float score, Date examDate, String remark) {
        this.id = id;
        this.studentId = studentId;
        this.courseId = courseId;
        this.score = score;
        this.examDate = examDate;
        this.remark = remark;
    }

    // getter and setter methods
}

### 数据库操作类

import java.sql.*;

public class Database {
    private Connection conn;

    public Database(String url, String username, String password) {
        try {
            Class.forName("com.mysql.jdbc.Driver");
            conn = DriverManager.getConnection(url, username, password);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    public void addStudent(Student student) {
        try {
            PreparedStatement pstmt = conn.prepareStatement(
                    "INSERT INTO student(id, name, gender, age, class) VALUES (?, ?, ?, ?, ?)");
            pstmt.setInt(1, student.getId());
            pstmt.setString(2, student.getName());
            pstmt.setString(3, student.getGender());
            pstmt.setInt(4, student.getAge());
            pstmt.setString(5, student.getClassName());
            pstmt.executeUpdate();
            pstmt.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    public void addCourse(Course course) {
        try {
            PreparedStatement pstmt = conn.prepareStatement(
                    "INSERT INTO course(id, name) VALUES (?, ?)");
            pstmt.setInt(1, course.getId());
            pstmt.setString(2, course.getName());
            pstmt.executeUpdate();
            pstmt.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    public void addScore(Score score) {
        try {
            PreparedStatement pstmt = conn.prepareStatement(
                    "INSERT INTO score(id, studentId, courseId, score, examDate, remark) VALUES (?, ?, ?, ?, ?, ?)");
            pstmt.setInt(1, score.getId());
            pstmt.setInt(2, score.getStudentId());
            pstmt.setInt(3, score.getCourseId());
            pstmt.setFloat(4, score.getScore());
            pstmt.setDate(5, new java.sql.Date(score.getExamDate().getTime()));
            pstmt.setString(6, score.getRemark());
            pstmt.executeUpdate();
            pstmt.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    public void close() {
        try {
            conn.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

### 测试代码

public class Test {
    public static void main(String[] args) {
        String url = "jdbc:mysql://localhost:3306/score";
        String username = "root";
        String password = "123456";
        Database db = new Database(url, username, password);

        Student student = new Student(1, "张三", "男", 18, "计算机科学与技术");
        db.addStudent(student);

        Course course = new Course(1, "Java程序设计");
        db.addCourse(course);

        Score score = new Score(1, 1, 1, 90.0f, new Date(System.currentTimeMillis()), "优秀");
        db.addScore(score);

        db.close();
    }
}

以上是一个简单的学生成绩管理系统的设计和实现，可以根据实际需求进行扩展和优化。