java程序设计之图书借阅管理系统代码事例

在Java程序设计中，图书借阅管理系统的代码示例通常涉及几个核心组件：用户、图书、图书馆以及相关的业务操作。下面是一个简单的例子，展示了如何创建实体类（如Book、Member、Library）以及它们之间的交互：

// 用户类
class Member {
    private String id;
    private String name;
    private List<Book> borrowedBooks;

    // 构造函数、getter/setter 和借书/还书方法
    public void borrow(Book book) {
        if (!book.isAvailable()) {
            throw new RuntimeException("这本书已被借出");
        }
        book.setBorrower(this);
        borrowedBooks.add(book);
    }

    // 还书方法
    public void returnBook(Book book) {
        book.setBorrower(null);
        borrowedBooks.remove(book);
    }
}

// 图书类
class Book {
    private String id;
    private String title;
    private Member borrower;
    private boolean isAvailable;

    // 同理，这里也有构造函数、getter/setter 和状态改变的方法
    public boolean isAvailable() {
        return borrower == null;
    }
}

// 图书馆类
class Library {
    private Map<String, Book> books;

    // 添加图书、查询图书和处理借阅等操作
    public void addBook(Book book) {
        books.put(book.getId(), book);
    }

    public void borrowBook(Member member, String bookId) {
        Book book = books.get(bookId);
        member.borrow(book);
    }

    public void returnBook(Member member, String bookId) {
        Book book = books.get(bookId);
        member.returnBook(book);
    }
}

// 示例主函数
public static void main(String[] args) {
    Library library = new Library();
    library.addBook(new Book("001", "Java编程入门"));
    Member member = new Member("M001", "Alice");

    // 借书和还书
    library.borrowBook(member, "001");
    member.returnBook(library.findBookById("001")); // 假设findBookById是一个辅助方法
}