Java写一个图书馆借书还书的程序

好的，以下是一个简单的Java图书馆借书还书的程序：

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

public class Library {

    private static ArrayList<String> books = new ArrayList<String>();
    private static ArrayList<String> borrowedBooks = new ArrayList<String>();

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int choice = 0;
        while (choice != 3) {
            System.out.println("请选择操作：");
            System.out.println("1. 借书");
            System.out.println("2. 还书");
            System.out.println("3. 退出");
            choice = scanner.nextInt();
            switch (choice) {
                case 1:
                    borrowBook();
                    break;
                case 2:
                    returnBook();
                    break;
                case 3:
                    System.out.println("谢谢使用！");
                    break;
                default:
                    System.out.println("无效的选择，请重新选择！");
                    break;
            }
        }
    }

    private static void borrowBook() {
        Scanner scanner = new Scanner(System.in);
        System.out.println("请输入要借的书名：");
        String book = scanner.nextLine();
        if (books.contains(book)) {
            books.remove(book);
            borrowedBooks.add(book);
            System.out.println("借书成功！");
        } else {
            System.out.println("抱歉，该书已被借出或不存在！");
        }
    }

    private static void returnBook() {
        Scanner scanner = new Scanner(System.in);
        System.out.println("请输入要还的书名：");
        String book = scanner.nextLine();
        if (borrowedBooks.contains(book)) {
            borrowedBooks.remove(book);
            books.add(book);
            System.out.println("还书成功！");
        } else {
            System.out.println("抱歉，您没有借过该书或书名有误！");
        }
    }
}

这个程序使用了两个ArrayList来存储图书馆中的书和已经被借出的书。用户可以选择借书或还书，程序会根据用户的选择进行相应的操作。