实战项目：基于控制台与数据库的图书管理系统开发指南

一、项目概述与设计思路

1.1 为什么选择图书管理系统

图书管理系统是学习编程的经典项目，它涵盖了：

控制台交互：学习用户输入输出处理
数据库操作：掌握CRUD核心功能
业务逻辑：理解实际应用场景
系统架构：实践分层设计思想

1.2 系统功能设计

核心功能模块：

1. 图书管理- 添加新书- 删除图书- 修改图书信息- 查询图书（按ID/书名/作者）2. 借阅管理- 图书借出- 图书归还- 借阅记录查询3. 用户管理- 读者注册- 读者信息修改- 读者注销4. 统计报表- 图书库存统计- 借阅排行榜- 逾期未还清单

1.3 技术选型

技术组件	选择方案	备注
开发语言	Java 8+	兼顾教学与实用
数据库	MySQL 8.0	免费开源，应用广泛
数据库连接	JDBC	学习原生数据库操作
控制台框架	-	纯Java实现
单元测试	JUnit 5	保证代码质量
日志系统	SLF4J + Logback	记录系统运行状态

二、数据库设计与实现

2.1 数据库表结构设计

ER图关键实体：

图书(Book) ---< 借阅记录(BorrowRecord) >--- 读者(Reader)

建表SQL：

-- 图书表
CREATE TABLE books (book_id INT AUTO_INCREMENT PRIMARY KEY,isbn VARCHAR(20) NOT NULL UNIQUE,title VARCHAR(100) NOT NULL,author VARCHAR(50) NOT NULL,publisher VARCHAR(50),publish_date DATE,price DECIMAL(10,2),stock INT DEFAULT 1 COMMENT '库存数量',create_time DATETIME DEFAULT CURRENT_TIMESTAMP
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;-- 读者表
CREATE TABLE readers (reader_id INT AUTO_INCREMENT PRIMARY KEY,name VARCHAR(50) NOT NULL,gender CHAR(1) CHECK (gender IN ('M', 'F')),phone VARCHAR(20),email VARCHAR(100),register_date DATE DEFAULT (CURRENT_DATE),membership_level INT DEFAULT 1
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;-- 借阅记录表
CREATE TABLE borrow_records (record_id INT AUTO_INCREMENT PRIMARY KEY,book_id INT NOT NULL,reader_id INT NOT NULL,borrow_date DATETIME DEFAULT CURRENT_TIMESTAMP,due_date DATETIME GENERATED ALWAYS AS (borrow_date + INTERVAL 30 DAY) STORED,return_date DATETIME,status TINYINT DEFAULT 1 COMMENT '1-借出 2-已还 3-逾期',FOREIGN KEY (book_id) REFERENCES books(book_id),FOREIGN KEY (reader_id) REFERENCES readers(reader_id)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;

2.2 索引优化设计

-- 提高查询性能的索引
CREATE INDEX idx_books_title ON books(title);
CREATE INDEX idx_books_author ON books(author);
CREATE INDEX idx_borrow_records_status ON borrow_records(status);
CREATE INDEX idx_borrow_records_due_date ON borrow_records(due_date);

2.3 初始化测试数据

-- 插入示例图书
INSERT INTO books (isbn, title, author, publisher, price, stock)
VALUES 
('9787111636667', 'Java核心技术 卷I', 'Cay S. Horstmann', '机械工业出版社', 119.00, 5),
('9787115523660', 'Effective Java', 'Joshua Bloch', '机械工业出版社', 129.00, 3),
('9787302515421', 'Python编程：从入门到实践', 'Eric Matthes', '人民邮电出版社', 89.00, 7);-- 插入示例读者
INSERT INTO readers (name, gender, phone, email)
VALUES 
('张三', 'M', '13800138001', 'zhangsan@example.com'),
('李四', 'F', '13900139001', 'lisi@example.com');

三、Java核心代码实现

3.1 数据库连接层

DBUtil.java - 数据库工具类：

public class DBUtil {private static final String URL = "jdbc:mysql://localhost:3306/library_db?useSSL=false&serverTimezone=UTC";private static final String USER = "root";private static final String PASSWORD = "123456";static {try {Class.forName("com.mysql.cj.jdbc.Driver");} catch (ClassNotFoundException e) {e.printStackTrace();}}public static Connection getConnection() throws SQLException {return DriverManager.getConnection(URL, USER, PASSWORD);}public static void close(Connection conn, Statement stmt, ResultSet rs) {try {if (rs != null) rs.close();if (stmt != null) stmt.close();if (conn != null) conn.close();} catch (SQLException e) {e.printStackTrace();}}
}

3.2 实体类设计

Book.java - 图书实体：

public class Book {private Integer bookId;private String isbn;private String title;private String author;private String publisher;private Date publishDate;private BigDecimal price;private Integer stock;// 构造方法、getter和setter省略// 建议使用Lombok @Data注解简化代码
}

3.3 数据访问层(DAO)

BookDAO.java - 图书数据访问：

public class BookDAO {// 添加新书public boolean addBook(Book book) {String sql = "INSERT INTO books (isbn, title, author, publisher, publish_date, price, stock) " +"VALUES (?, ?, ?, ?, ?, ?, ?)";try (Connection conn = DBUtil.getConnection();PreparedStatement pstmt = conn.prepareStatement(sql)) {pstmt.setString(1, book.getIsbn());pstmt.setString(2, book.getTitle());pstmt.setString(3, book.getAuthor());pstmt.setString(4, book.getPublisher());pstmt.setDate(5, new java.sql.Date(book.getPublishDate().getTime()));pstmt.setBigDecimal(6, book.getPrice());pstmt.setInt(7, book.getStock());return pstmt.executeUpdate() > 0;} catch (SQLException e) {e.printStackTrace();return false;}}// 按ID查询图书public Book getBookById(int bookId) {String sql = "SELECT * FROM books WHERE book_id = ?";Book book = null;try (Connection conn = DBUtil.getConnection();PreparedStatement pstmt = conn.prepareStatement(sql)) {pstmt.setInt(1, bookId);try (ResultSet rs = pstmt.executeQuery()) {if (rs.next()) {book = new Book();book.setBookId(rs.getInt("book_id"));book.setIsbn(rs.getString("isbn"));// 设置其他属性...}}} catch (SQLException e) {e.printStackTrace();}return book;}// 其他CRUD方法...
}

3.4 业务逻辑层(Service)

LibraryService.java - 核心业务逻辑：

public class LibraryService {private BookDAO bookDAO = new BookDAO();private ReaderDAO readerDAO = new ReaderDAO();private BorrowRecordDAO recordDAO = new BorrowRecordDAO();// 借书业务方法public boolean borrowBook(int bookId, int readerId) {// 检查图书库存Book book = bookDAO.getBookById(bookId);if (book == null || book.getStock() <= 0) {System.out.println("图书不存在或库存不足");return false;}// 检查读者是否存在Reader reader = readerDAO.getReaderById(readerId);if (reader == null) {System.out.println("读者不存在");return false;}// 检查是否已借过同一本书未还if (recordDAO.hasUnreturnedRecord(bookId, readerId)) {System.out.println("您已借阅该书且未归还");return false;}// 开启事务Connection conn = null;try {conn = DBUtil.getConnection();conn.setAutoCommit(false);// 1. 减少库存bookDAO.updateStock(conn, bookId, -1);// 2. 创建借阅记录BorrowRecord record = new BorrowRecord();record.setBookId(bookId);record.setReaderId(readerId);recordDAO.addRecord(conn, record);conn.commit();return true;} catch (SQLException e) {if (conn != null) {try {conn.rollback();} catch (SQLException ex) {ex.printStackTrace();}}e.printStackTrace();return false;} finally {if (conn != null) {try {conn.setAutoCommit(true);conn.close();} catch (SQLException e) {e.printStackTrace();}}}}// 其他业务方法...
}

3.5 控制台界面实现

ConsoleUI.java - 用户交互界面：

public class ConsoleUI {private Scanner scanner = new Scanner(System.in);private LibraryService libraryService = new LibraryService();public void start() {while (true) {showMainMenu();int choice = getIntInput("请选择操作：");switch (choice) {case 1:manageBooks();break;case 2:manageReaders();break;case 3:manageBorrowing();break;case 4:generateReports();break;case 0:System.out.println("感谢使用图书管理系统，再见！");return;default:System.out.println("无效选择，请重新输入");}}}private void showMainMenu() {System.out.println("\n===== 图书管理系统 =====");System.out.println("1. 图书管理");System.out.println("2. 读者管理");System.out.println("3. 借阅管理");System.out.println("4. 统计报表");System.out.println("0. 退出系统");}private void manageBooks() {while (true) {System.out.println("\n===== 图书管理 =====");System.out.println("1. 添加新书");System.out.println("2. 查询图书");System.out.println("3. 修改图书信息");System.out.println("4. 删除图书");System.out.println("0. 返回上级菜单");int choice = getIntInput("请选择操作：");switch (choice) {case 1:addNewBook();break;case 2:searchBooks();break;// 其他case...case 0:return;default:System.out.println("无效选择");}}}private void addNewBook() {System.out.println("\n--- 添加新书 ---");String isbn = getStringInput("ISBN：");String title = getStringInput("书名：");String author = getStringInput("作者：");Book book = new Book();book.setIsbn(isbn);book.setTitle(title);book.setAuthor(author);// 设置其他属性...if (libraryService.addBook(book)) {System.out.println("添加图书成功！");} else {System.out.println("添加图书失败");}}// 其他方法...private int getIntInput(String prompt) {while (true) {try {System.out.print(prompt);return Integer.parseInt(scanner.nextLine());} catch (NumberFormatException e) {System.out.println("请输入有效数字！");}}}private String getStringInput(String prompt) {System.out.print(prompt);return scanner.nextLine();}
}

四、项目扩展与优化

4.1 功能扩展建议

预约功能：
- 允许读者预约已被借出的图书
- 图书归还时通知预约读者
逾期罚款：
- 计算逾期天数
- 按规则自动计算罚款金额
图书推荐：
- 基于借阅历史的简单推荐
- 热门图书推荐

4.2 代码优化方向

引入连接池：

// 使用HikariCP替代原生JDBC连接
HikariConfig config = new HikariConfig();
config.setJdbcUrl("jdbc:mysql://localhost:3306/library_db");
config.setUsername("root");
config.setPassword("123456");
HikariDataSource dataSource = new HikariDataSource(config);

使用DAO接口：

public interface BookDAO {boolean addBook(Book book);Book getBookById(int bookId);// 其他方法...
}public class BookDAOImpl implements BookDAO {// 实现方法...
}

日志记录：

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;public class BookDAOImpl implements BookDAO {private static final Logger logger = LoggerFactory.getLogger(BookDAOImpl.class);public boolean addBook(Book book) {logger.debug("尝试添加图书：{}", book.getTitle());// 实现代码...}
}

4.3 异常处理改进

自定义异常类：

public class LibraryException extends Exception {public LibraryException(String message) {super(message);}public LibraryException(String message, Throwable cause) {super(message, cause);}
}// 使用示例
public void borrowBook(int bookId, int readerId) throws LibraryException {try {// 业务逻辑...} catch (SQLException e) {throw new LibraryException("借书操作失败", e);}
}

五、项目部署与测试

5.1 单元测试示例

BookDAOTest.java：

public class BookDAOTest {private BookDAO bookDAO = new BookDAOImpl();@Testpublic void testAddAndGetBook() {Book book = new Book();book.setIsbn("978-3-16-148410-0");book.setTitle("测试图书");book.setAuthor("测试作者");boolean added = bookDAO.addBook(book);assertTrue(added);Book retrieved = bookDAO.getBookByIsbn("978-3-16-148410-0");assertNotNull(retrieved);assertEquals("测试图书", retrieved.getTitle());}// 其他测试方法...
}