Java 图书管理系统代码示例 - 简单易懂的实现

下面是一个简单的 Java 图书管理系统的代码示例：

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

class Book {
    private String title;
    private String author;
    private int year;

    public Book(String title, String author, int year) {
        this.title = title;
        this.author = author;
        this.year = year;
    }

    public String getTitle() {
        return title;
    }

    public String getAuthor() {
        return author;
    }

    public int getYear() {
        return year;
    }
}

class Library {
    private List<Book> books;

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

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

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

    public List<Book> searchByTitle(String title) {
        List<Book> result = new ArrayList<>();
        for (Book book : books) {
            if (book.getTitle().equalsIgnoreCase(title)) {
                result.add(book);
            }
        }
        return result;
    }

    public List<Book> searchByAuthor(String author) {
        List<Book> result = new ArrayList<>();
        for (Book book : books) {
            if (book.getAuthor().equalsIgnoreCase(author)) {
                result.add(book);
            }
        }
        return result;
    }

    public List<Book> searchByYear(int year) {
        List<Book> result = new ArrayList<>();
        for (Book book : books) {
            if (book.getYear() == year) {
                result.add(book);
            }
        }
        return result;
    }
}

public class Main {
    public static void main(String[] args) {
        Library library = new Library();
        Scanner scanner = new Scanner(System.in);

        while (true) {
            System.out.println("1. Add book");
            System.out.println("2. Remove book");
            System.out.println("3. Search by title");
            System.out.println("4. Search by author");
            System.out.println("5. Search by year");
            System.out.println("6. Quit");
            System.out.print("Enter your choice: ");
            int choice = scanner.nextInt();

            switch (choice) {
                case 1:
                    System.out.print("Enter book title: ");
                    String title = scanner.next();
                    System.out.print("Enter book author: ");
                    String author = scanner.next();
                    System.out.print("Enter book year: ");
                    int year = scanner.nextInt();
                    Book book = new Book(title, author, year);
                    library.addBook(book);
                    System.out.println("Book added successfully.");
                    break;
                case 2:
                    System.out.print("Enter book title: ");
                    title = scanner.next();
                    System.out.print("Enter book author: ");
                    author = scanner.next();
                    System.out.print("Enter book year: ");
                    year = scanner.nextInt();
                    book = new Book(title, author, year);
                    library.removeBook(book);
                    System.out.println("Book removed successfully.");
                    break;
                case 3:
                    System.out.print("Enter book title: ");
                    title = scanner.next();
                    List<Book> searchResult = library.searchByTitle(title);
                    if (searchResult.isEmpty()) {
                        System.out.println("No matching books found.");
                    } else {
                        System.out.println("Matching books:");
                        for (Book b : searchResult) {
                            System.out.println(b.getTitle() + " by " + b.getAuthor() + " (" + b.getYear() + ")");
                        }
                    }
                    break;
                case 4:
                    System.out.print("Enter book author: ");
                    author = scanner.next();
                    searchResult = library.searchByAuthor(author);
                    if (searchResult.isEmpty()) {
                        System.out.println("No matching books found.");
                    } else {
                        System.out.println("Matching books:");
                        for (Book b : searchResult) {
                            System.out.println(b.getTitle() + " by " + b.getAuthor() + " (" + b.getYear() + ")");
                        }
                    }
                    break;
                case 5:
                    System.out.print("Enter book year: ");
                    year = scanner.nextInt();
                    searchResult = library.searchByYear(year);
                    if (searchResult.isEmpty()) {
                        System.out.println("No matching books found.");
                    } else {
                        System.out.println("Matching books:");
                        for (Book b : searchResult) {
                            System.out.println(b.getTitle() + " by " + b.getAuthor() + " (" + b.getYear() + ")");
                        }
                    }
                    break;
                case 6:
                    System.out.println("Exiting...");
                    System.exit(0);
                    break;
                default:
                    System.out.println("Invalid choice. Please try again.");
            }
        }
    }
}

这个代码实现了一个简单的图书管理系统，用户可以选择添加书籍、删除书籍、按标题、作者或年份搜索书籍。用户可以在控制台中输入选择，并根据选择执行相应的操作。