图书馆管理系统：开发一个图书馆管理系统，包括图书的分类、借阅、归还、查询等功能。用JAVA实现

好的，首先需要设计数据库来存储图书和借阅信息。可以设计两张表，一张存储图书信息，另一张存储借阅信息。

图书信息表包括以下字段：

- book_id: 图书编号，主键
- book_name: 图书名称
- author: 作者
- category: 分类
- publisher: 出版社
- publish_date: 出版日期
- price: 价格
- status: 状态（在库、借出）

借阅信息表包括以下字段：

- borrow_id: 借阅编号，主键
- book_id: 图书编号，外键
- user_id: 借阅者编号，外键
- borrow_date: 借阅日期
- return_date: 归还日期

接下来是JAVA代码实现，大致分为以下几个模块：

1. 数据库连接模块

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;

public class DatabaseConnection {
    private static final String URL = "jdbc:mysql://localhost:3306/library";
    private static final String USER = "root";
    private static final String PASSWORD = "password";

    public static Connection getConnection() throws SQLException {
        return DriverManager.getConnection(URL, USER, PASSWORD);
    }
}

2. 图书管理模块

import java.sql.*;
import java.util.ArrayList;
import java.util.List;

public class BookManager {
    public static List<Book> getAllBooks() {
        List<Book> books = new ArrayList<>();
        try (Connection conn = DatabaseConnection.getConnection();
             Statement stmt = conn.createStatement();
             ResultSet rs = stmt.executeQuery("SELECT * FROM book")) {
            while (rs.next()) {
                Book book = new Book();
                book.setId(rs.getInt("book_id"));
                book.setName(rs.getString("book_name"));
                book.setAuthor(rs.getString("author"));
                book.setCategory(rs.getString("category"));
                book.setPublisher(rs.getString("publisher"));
                book.setPublishDate(rs.getDate("publish_date"));
                book.setPrice(rs.getDouble("price"));
                book.setStatus(rs.getString("status"));
                books.add(book);
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }
        return books;
    }

    public static List<Book> searchBooks(String keyword) {
        List<Book> books = new ArrayList<>();
        String sql = "SELECT * FROM book WHERE book_name LIKE ? OR author LIKE ? OR category LIKE ?";
        try (Connection conn = DatabaseConnection.getConnection();
             PreparedStatement pstmt = conn.prepareStatement(sql)) {
            pstmt.setString(1, "%" + keyword + "%");
            pstmt.setString(2, "%" + keyword + "%");
            pstmt.setString(3, "%" + keyword + "%");
            ResultSet rs = pstmt.executeQuery();
            while (rs.next()) {
                Book book = new Book();
                book.setId(rs.getInt("book_id"));
                book.setName(rs.getString("book_name"));
                book.setAuthor(rs.getString("author"));
                book.setCategory(rs.getString("category"));
                book.setPublisher(rs.getString("publisher"));
                book.setPublishDate(rs.getDate("publish_date"));
                book.setPrice(rs.getDouble("price"));
                book.setStatus(rs.getString("status"));
                books.add(book);
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }
        return books;
    }

    public static boolean addBook(Book book) {
        String sql = "INSERT INTO book (book_name, author, category, publisher, publish_date, price, status) VALUES (?, ?, ?, ?, ?, ?, ?)";
        try (Connection conn = DatabaseConnection.getConnection();
             PreparedStatement pstmt = conn.prepareStatement(sql)) {
            pstmt.setString(1, book.getName());
            pstmt.setString(2, book.getAuthor());
            pstmt.setString(3, book.getCategory());
            pstmt.setString(4, book.getPublisher());
            pstmt.setDate(5, new Date(book.getPublishDate().getTime()));
            pstmt.setDouble(6, book.getPrice());
            pstmt.setString(7, book.getStatus());
            int rows = pstmt.executeUpdate();
            return rows > 0;
        } catch (SQLException e) {
            e.printStackTrace();
        }
        return false;
    }

    public static boolean deleteBook(int bookId) {
        String sql = "DELETE FROM book WHERE book_id=?";
        try (Connection conn = DatabaseConnection.getConnection();
             PreparedStatement pstmt = conn.prepareStatement(sql)) {
            pstmt.setInt(1, bookId);
            int rows = pstmt.executeUpdate();
            return rows > 0;
        } catch (SQLException e) {
            e.printStackTrace();
        }
        return false;
    }

    public static boolean updateBook(Book book) {
        String sql = "UPDATE book SET book_name=?, author=?, category=?, publisher=?, publish_date=?, price=?, status=? WHERE book_id=?";
        try (Connection conn = DatabaseConnection.getConnection();
             PreparedStatement pstmt = conn.prepareStatement(sql)) {
            pstmt.setString(1, book.getName());
            pstmt.setString(2, book.getAuthor());
            pstmt.setString(3, book.getCategory());
            pstmt.setString(4, book.getPublisher());
            pstmt.setDate(5, new Date(book.getPublishDate().getTime()));
            pstmt.setDouble(6, book.getPrice());
            pstmt.setString(7, book.getStatus());
            pstmt.setInt(8, book.getId());
            int rows = pstmt.executeUpdate();
            return rows > 0;
        } catch (SQLException e) {
            e.printStackTrace();
        }
        return false;
    }
}

3. 借阅管理模块

import java.sql.*;
import java.util.ArrayList;
import java.util.List;

public class BorrowManager {
    public static List<Borrow> getAllBorrows() {
        List<Borrow> borrows = new ArrayList<>();
        try (Connection conn = DatabaseConnection.getConnection();
             Statement stmt = conn.createStatement();
             ResultSet rs = stmt.executeQuery("SELECT * FROM borrow")) {
            while (rs.next()) {
                Borrow borrow = new Borrow();
                borrow.setId(rs.getInt("borrow_id"));
                borrow.setBookId(rs.getInt("book_id"));
                borrow.setUserId(rs.getInt("user_id"));
                borrow.setBorrowDate(rs.getDate("borrow_date"));
                borrow.setReturnDate(rs.getDate("return_date"));
                borrows.add(borrow);
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }
        return borrows;
    }

    public static List<Borrow> searchBorrows(int userId) {
        List<Borrow> borrows = new ArrayList<>();
        String sql = "SELECT * FROM borrow WHERE user_id=?";
        try (Connection conn = DatabaseConnection.getConnection();
             PreparedStatement pstmt = conn.prepareStatement(sql)) {
            pstmt.setInt(1, userId);
            ResultSet rs = pstmt.executeQuery();
            while (rs.next()) {
                Borrow borrow = new Borrow();
                borrow.setId(rs.getInt("borrow_id"));
                borrow.setBookId(rs.getInt("book_id"));
                borrow.setUserId(rs.getInt("user_id"));
                borrow.setBorrowDate(rs.getDate("borrow_date"));
                borrow.setReturnDate(rs.getDate("return_date"));
                borrows.add(borrow);
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }
        return borrows;
    }

    public static boolean borrowBook(int bookId, int userId) {
        String sql = "INSERT INTO borrow (book_id, user_id, borrow_date) VALUES (?, ?, ?)";
        try (Connection conn = DatabaseConnection.getConnection();
             PreparedStatement pstmt = conn.prepareStatement(sql)) {
            pstmt.setInt(1, bookId);
            pstmt.setInt(2, userId);
            pstmt.setDate(3, new Date(System.currentTimeMillis()));
            int rows = pstmt.executeUpdate();
            return rows > 0;
        } catch (SQLException e) {
            e.printStackTrace();
        }
        return false;
    }

    public static boolean returnBook(int borrowId) {
        String sql = "UPDATE borrow SET return_date=? WHERE borrow_id=?";
        try (Connection conn = DatabaseConnection.getConnection();
             PreparedStatement pstmt = conn.prepareStatement(sql)) {
            pstmt.setDate(1, new Date(System.currentTimeMillis()));
            pstmt.setInt(2, borrowId);
            int rows = pstmt.executeUpdate();
            return rows > 0;
        } catch (SQLException e) {
            e.printStackTrace();
        }
        return false;
    }
}

4. 用户界面模块

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

public class UserInterface {
    private static final Scanner scanner = new Scanner(System.in);

    public static void main(String[] args) {
        while (true) {
            System.out.println("欢迎使用图书馆管理系统！");
            System.out.println("1. 查看所有图书");
            System.out.println("2. 搜索图书");
            System.out.println("3. 借阅图书");
            System.out.println("4. 归还图书");
            System.out.println("5. 退出系统");
            System.out.print("请输入选项：");
            int choice = scanner.nextInt();
            switch (choice) {
                case 1:
                    showAllBooks();
                    break;
                case 2:
                    searchBooks();
                    break;
                case 3:
                    borrowBook();
                    break;
                case 4:
                    returnBook();
                    break;
                case 5:
                    System.out.println("再见！");
                    System.exit(0);
                default:
                    System.out.println("输入有误，请重新输入！");
                    break;
            }
        }
    }

    private static void showAllBooks() {
        List<Book> books = BookManager.getAllBooks();
        if (books.isEmpty()) {
            System.out.println("暂无图书信息！");
        } else {
            System.out.println("所有图书信息如下：");
            for (Book book : books) {
                System.out.println(book);
            }
        }
    }

    private static void searchBooks() {
        System.out.print("请输入关键词：");
        String keyword = scanner.next();
        List<Book> books = BookManager.searchBooks(keyword);
        if (books.isEmpty()) {
            System.out.println("未找到符合条件的图书！");
        } else {
            System.out.println("搜索结果如下：");
            for (Book book : books) {
                System.out.println(book);
            }
        }
    }

    private static void borrowBook() {
        System.out.print("请输入要借阅的图书编号：");
        int bookId = scanner.nextInt();
        System.out.print("请输入您的编号：");
        int userId = scanner.nextInt();
        boolean result = BorrowManager.borrowBook(bookId, userId);
        if (result) {
            System.out.println("借阅成功！");
        } else {
            System.out.println("借阅失败！");
        }
    }

    private static void returnBook() {
        System.out.print("请输入要归还的借阅编号：");
        int borrowId = scanner.nextInt();
        boolean result = BorrowManager.returnBook(borrowId);
        if (result) {
            System.out.println("归还成功！");
        } else {
            System.out.println("归还失败！");
        }
    }
}

以上就是图书馆管理系统的JAVA实现。需要注意的是，本系统仅作为示例，还有很多细节问题需要考虑，比如数据库连接池、异常处理、并发控制等等。