使用java语言写一个图书管管理系统

好的，下面是一个简单的图书管理系统的Java代码示例：

import java.util.ArrayList;
import java.util.Scanner;

public class BookManagementSystem {
    private ArrayList<Book> books;

    public BookManagementSystem() {
        books = new ArrayList<Book>();
    }

    public void addBook(Book book) {
        books.add(book);
    }

    public void removeBook(Book book) {
        books.remove(book);
    }

    public void displayAllBooks() {
        System.out.println("All books:");
        for (Book book : books) {
            System.out.println(book);
        }
    }

    public void displayAvailableBooks() {
        System.out.println("Available books:");
        for (Book book : books) {
            if (book.isAvailable()) {
                System.out.println(book);
            }
        }
    }

    public void displayBorrowedBooks() {
        System.out.println("Borrowed books:");
        for (Book book : books) {
            if (!book.isAvailable()) {
                System.out.println(book);
            }
        }
    }

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        BookManagementSystem system = new BookManagementSystem();
        boolean running = true;

        while (running) {
            System.out.println("Commands:");
            System.out.println("1. Add book");
            System.out.println("2. Remove book");
            System.out.println("3. Display all books");
            System.out.println("4. Display available books");
            System.out.println("5. Display borrowed books");
            System.out.println("6. Exit");

            int command = scanner.nextInt();
            scanner.nextLine();

            switch (command) {
                case 1:
                    System.out.println("Enter book title:");
                    String title = scanner.nextLine();
                    System.out.println("Enter book author:");
                    String author = scanner.nextLine();
                    system.addBook(new Book(title, author));
                    break;
                case 2:
                    System.out.println("Enter book title:");
                    title = scanner.nextLine();
                    System.out.println("Enter book author:");
                    author = scanner.nextLine();
                    Book bookToRemove = new Book(title, author);
                    if (system.books.contains(bookToRemove)) {
                        system.removeBook(bookToRemove);
                    } else {
                        System.out.println("Book not found!");
                    }
                    break;
                case 3:
                    system.displayAllBooks();
                    break;
                case 4:
                    system.displayAvailableBooks();
                    break;
                case 5:
                    system.displayBorrowedBooks();
                    break;
                case 6:
                    running = false;
                    break;
                default:
                    System.out.println("Invalid command!");
                    break;
            }
        }
    }
}

class Book {
    private String title;
    private String author;
    private boolean available;

    public Book(String title, String author) {
        this.title = title;
        this.author = author;
        this.available = true;
    }

    public String getTitle() {
        return title;
    }

    public String getAuthor() {
        return author;
    }

    public boolean isAvailable() {
        return available;
    }

    public void setAvailable(boolean available) {
        this.available = available;
    }

    @Override
    public String toString() {
        return title + " by " + author + " (" + (available ? "available" : "borrowed") + ")";
    }

    @Override
    public boolean equals(Object obj) {
        if (obj == null || getClass() != obj.getClass()) {
            return false;
        }
        final Book other = (Book) obj;
        if ((this.title == null) ? (other.title != null) : !this.title.equals(other.title)) {
            return false;
        }
        if ((this.author == null) ? (other.author != null) : !this.author.equals(other.author)) {
            return false;
        }
        return true;
    }

    @Override
    public int hashCode() {
        int hash = 7;
        hash = 31 * hash + (this.title != null ? this.title.hashCode() : 0);
        hash = 31 * hash + (this.author != null ? this.author.hashCode() : 0);
        return hash;
    }
}

这是一个基本的命令行界面的图书管理系统，你可以根据需要进行修改和扩展。