• 日期: 2026-01-07 00:01:40
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构建在线考试系统：数据库与 Java 代码示例

概述

本文将指导您使用数据库和 Java 创建一个简单的在线考试系统。我们将介绍数据库设计、学生和教师功能以及代码示例，帮助您了解构建此类系统的基本原理。

数据库设计

我们将使用以下表格来存储考试系统的数据：

  • students: 存储学生信息 - student_id INT PRIMARY KEY - name VARCHAR(50) - password VARCHAR(50)- courses: 存储课程信息 - course_id INT PRIMARY KEY - course_name VARCHAR(100)- questions: 存储考试题目 - question_id INT PRIMARY KEY - course_id INT, - question_text VARCHAR(500) - option_a VARCHAR(100) - option_b VARCHAR(100) - option_c VARCHAR(100) - option_d VARCHAR(100) - correct_answer VARCHAR(1) - FOREIGN KEY (course_id) REFERENCES courses(course_id)- exam_results: 存储考试结果 - student_id INT - course_id INT - score INT - PRIMARY KEY (student_id, course_id) - FOREIGN KEY (student_id) REFERENCES students(student_id) - FOREIGN KEY (course_id) REFERENCES courses(course_id)- teachers: 存储教师信息 - teacher_id INT PRIMARY KEY - name VARCHAR(50) - password VARCHAR(50)- teacher_courses: 存储教师与课程的关联关系 - teacher_id INT - course_id INT - PRIMARY KEY (teacher_id, course_id) - FOREIGN KEY (teacher_id) REFERENCES teachers(teacher_id) - FOREIGN KEY (course_id) REFERENCES courses(course_id)

数据库创建脚本

以下是创建数据库和表格的 SQL 脚本：sqlCREATE DATABASE exam;USE exam;

CREATE TABLE students ( student_id INT PRIMARY KEY, name VARCHAR(50), password VARCHAR(50));

CREATE TABLE courses ( course_id INT PRIMARY KEY, course_name VARCHAR(100));

CREATE TABLE questions ( question_id INT PRIMARY KEY, course_id INT, question_text VARCHAR(500), option_a VARCHAR(100), option_b VARCHAR(100), option_c VARCHAR(100), option_d VARCHAR(100), correct_answer VARCHAR(1), FOREIGN KEY (course_id) REFERENCES courses(course_id));

CREATE TABLE exam_results ( student_id INT, course_id INT, score INT, PRIMARY KEY (student_id, course_id), FOREIGN KEY (student_id) REFERENCES students(student_id), FOREIGN KEY (course_id) REFERENCES courses(course_id));

CREATE TABLE teachers ( teacher_id INT PRIMARY KEY, name VARCHAR(50), password VARCHAR(50));

CREATE TABLE teacher_courses ( teacher_id INT, course_id INT, PRIMARY KEY (teacher_id, course_id), FOREIGN KEY (teacher_id) REFERENCES teachers(teacher_id), FOREIGN KEY (course_id) REFERENCES courses(course_id));

-- 创建新用户并授予权限CREATE USER 'new_user'@'localhost' IDENTIFIED BY 'password';GRANT ALL PRIVILEGES ON exam.* TO 'new_user'@'localhost';

Java 代码实现

以下是使用 Java 实现考试系统基本功能的示例代码：javapackage exam;

import java.util.Scanner;import java.sql.Connection;import java.sql.PreparedStatement;import java.sql.ResultSet;import java.sql.SQLException;

public class ExamManagementSystem {

public static void main(String[] args) {        Scanner scanner = new Scanner(System.in);        System.out.println('Select Language:');        System.out.println('1. 中文');        System.out.println('2. English');        int langChoice = scanner.nextInt();

    switch (langChoice) {            case 1:                // 中文界面逻辑                break;            case 2:                // 英文界面逻辑                break;            default:                System.out.println('Invalid option!');                break;        }    }        // 学生注册    public static void studentRegistration() {        Scanner scanner = new Scanner(System.in);        System.out.println('请输入学号：');        int studentId = scanner.nextInt();        System.out.println('请输入姓名：');        scanner.nextLine();         String name = scanner.nextLine();        System.out.println('请输入密码：');        String password = scanner.nextLine();        System.out.println('请再次输入密码：');        String confirmPassword = scanner.nextLine();                if (!password.equals(confirmPassword)) {            System.out.println('两次输入的密码不一致，请重新注册！');            return;        }                // 将学生信息插入到数据库中        try (Connection conn = DatabaseConnector.getConnection()) {            String sql = 'INSERT INTO students (student_id, name, password) VALUES (?, ?, ?)';            PreparedStatement statement = conn.prepareStatement(sql);            statement.setInt(1, studentId);            statement.setString(2, name);            statement.setString(3, password);            statement.executeUpdate();            System.out.println('注册成功！');        } catch (SQLException e) {            e.printStackTrace();            System.out.println('注册失败，请重新尝试！');        }    }        // 学生登录    public static void studentLogin() {        Scanner scanner = new Scanner(System.in);        System.out.println('请输入学号：');        int studentId = scanner.nextInt();        System.out.println('请输入密码：');        String password = scanner.next();                // 查询数据库验证学生登录信息        try (Connection conn = DatabaseConnector.getConnection()) {            String sql = 'SELECT * FROM students WHERE student_id = ? AND password = ?';            PreparedStatement statement = conn.prepareStatement(sql);            statement.setInt(1, studentId);            statement.setString(2, password);            ResultSet result = statement.executeQuery();            if (result.next()) {                System.out.println('登录成功！');                // 登录成功后的逻辑            } else {                System.out.println('学号或密码错误，请重新登录！');                studentLogin();             }        } catch (SQLException e) {            e.printStackTrace();            System.out.println('登录失败，请重新尝试！');        }    }

// 学生开始考试    public static void studentStartExam() {        Scanner scanner = new Scanner(System.in);        System.out.println('请输入您的学号：');        int studentId = scanner.nextInt();        System.out.println('请选择您要考试的学科：');        System.out.println('1. Mathematics');        System.out.println('2. English');        System.out.println('3. Science');        int subjectChoice = scanner.nextInt();

    String subject = '';        int totalQuestions = 0;        switch (subjectChoice) {            case 1:                subject = 'Mathematics';                totalQuestions = 2; // 假设每个科目只有2道题                break;            case 2:                subject = 'English';                totalQuestions = 2;                break;            case 3:                subject = 'Science';                totalQuestions = 2;                break;            default:                System.out.println('无效的选项！');                return;        }

    int score = 0;        for (int i = 1; i <= totalQuestions; i++) {            System.out.println('问题 ' + i + ':');            // 从数据库中获取题目            try (Connection conn = DatabaseConnector.getConnection()) {                String sql = 'SELECT * FROM questions WHERE course_name = ? ORDER BY RAND() LIMIT 1';                PreparedStatement statement = conn.prepareStatement(sql);                statement.setString(1, subject);                ResultSet result = statement.executeQuery();                if (result.next()) {                    String question = result.getString('question_text');                    String optionA = result.getString('option_a');                    String optionB = result.getString('option_b');                    String optionC = result.getString('option_c');                    String optionD = result.getString('option_d');                    String answer = result.getString('correct_answer');

                System.out.println(question);                    System.out.println('A. ' + optionA);                    System.out.println('B. ' + optionB);                    System.out.println('C. ' + optionC);                    System.out.println('D. ' + optionD);                    System.out.println('请选择您的答案：');                    scanner.nextLine();                    String studentAnswer = scanner.nextLine();

                if (studentAnswer.equalsIgnoreCase(answer)) {                        score += 10;                        System.out.println('回答正确！');                    } else {                        System.out.println('回答错误！');                    }                }            } catch (SQLException e) {                e.printStackTrace();                System.out.println('获取题目失败！');            }

        if (i < totalQuestions) {                System.out.println('请选择您要进行的操作：');                System.out.println('1. 下一题');                System.out.println('2. 完成答题');                int answerChoice = scanner.nextInt();

            if (answerChoice == 2) {                    break;                }            }        }

    System.out.println('您的得分是：' + score);

    // 将学生的分数保存到数据库中        try (Connection conn = DatabaseConnector.getConnection()) {            String sql = 'INSERT INTO exam_results (student_id, course_id, score) VALUES (?, ?, ?)';            PreparedStatement statement = conn.prepareStatement(sql);            statement.setInt(1, studentId);            statement.setInt(2, subjectChoice); // 使用 subjectChoice 作为 course_id            statement.setInt(3, score);            statement.executeUpdate();            System.out.println('分数已保存！');        } catch (SQLException e) {            e.printStackTrace();            System.out.println('保存分数失败！');        }    }

// 教师登录    public static void teacherLogin() {        // 教师登录逻辑
构建在线考试系统：数据库与 Java 代码示例

原文地址: https://www.cveoy.top/t/topic/f0Af 著作权归作者所有。请勿转载和采集!

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