借阅图书管理模块代码

### 借阅图书管理模块的实现代码示例 以下是基于 Java 的借阅图书管理模块的一个简单实现。此代码展示了如何通过面向对象的方式完成图书借阅的核心逻辑。 #### 1. 图书类 (Book.java) ```java public class Book { private String bookId; private String title; private boolean isAvailable; public Book(String bookId, String title) { this.bookId = bookId; this.title = title; this.isAvailable = true; // 默认书籍可用 } public String getBookId() { return bookId; } public String getTitle() { return title; } public boolean isAvailable() { return isAvailable; } public void setAvailability(boolean availability) { this.isAvailable = availability; } } ``` #### 2. 用户类 (User.java) ```java public class User { private String userId; private String name; public User(String userId, String name) { this.userId = userId; this.name = name; } public String getUserId() { return userId; } public String getName() { return name; } } ``` #### 3. 借阅记录类 (BorrowRecord.java) ```java import java.util.Date; public class BorrowRecord { private String recordId; private Book book; private User user; private Date borrowDate; private Date dueDate; public BorrowRecord(Book book, User user, Date borrowDate, Date dueDate) { this.recordId = generateUniqueId(); // 自动生成唯一ID this.book = book; this.user = user; this.borrowDate = borrowDate; this.dueDate = dueDate; } private String generateUniqueId() { // 这里可以使用更复杂的算法来生成唯一的记录ID return System.currentTimeMillis() + "-" + Math.random(); } public String getRecordId() { return recordId; } public Book getBook() { return book; } public User getUser() { return user; } public Date getBorrowDate() { return borrowDate; } public Date getDueDate() { return dueDate; } @Override public String toString() { return "Record ID: " + recordId + ", Book Title: " + book.getTitle() + ", User Name: " + user.getName() + ", Borrowed on: " + borrowDate.toString() + ", Due by: " + dueDate.toString(); } } ``` #### 4. 借阅管理器类 (LibraryManager.java) ```java import java.util.ArrayList; import java.util.Date; import java.util.List; public class LibraryManager { private List<Book> books; private List<User> users; private List<BorrowRecord> records; public LibraryManager() { this.books = new ArrayList<>(); this.users = new ArrayList<>(); this.records = new ArrayList<>(); } public void addBook(Book book) { books.add(book); } public void addUser(User user) { users.add(user); } public void borrowBook(String bookId, String userId, int daysToReturn) throws Exception { Book selectedBook = null; User selectedUser = null; for (Book b : books) { if (b.getBookId().equals(bookId)) { selectedBook = b; break; } } for (User u : users) { if (u.getUserId().equals(userId)) { selectedUser = u; break; } } if (selectedBook == null || !selectedBook.isAvailable()) { throw new Exception("The requested book is not available."); } else if (selectedUser == null) { throw new Exception("Invalid user ID provided."); } else { Date today = new Date(); long millisInDay = 1000L * 60 * 60 * 24; Date dueDate = new Date(today.getTime() + (daysToReturn * millisInDay)); BorrowRecord record = new BorrowRecord(selectedBook, selectedUser, today, dueDate); records.add(record); selectedBook.setAvailability(false); // 设置书籍不可用状态 } } public void returnBook(String bookId) throws Exception { for (Book b : books) { if (b.getBookId().equals(bookId)) { if (!b.isAvailable()) { b.setAvailability(true); // 归还后设置书籍为可用 } else { throw new Exception("This book has already been returned or was never borrowed."); } break; } } } public void displayAllRecords() { for (BorrowRecord r : records) { System.out.println(r.toString()); } } } ``` 以上是一个简单的图书馆管理系统中的借阅部分实现[^1]。它涵盖了基本的功能需求，如用户注册、图书添加、借阅操作以及归还处理等核心功能[^3]。 ---