Book.java

// Abstract class representing a book
abstract class Book {
    private String title;
    private String author;
    private int publicationYear;

    // Constructor
    public Book(String title, String author, int publicationYear) {
        this.title = title;
        this.author = author;
        this.publicationYear = publicationYear;
    }

    // Abstract method to be implemented by subclasses
    public abstract double calculateLateFee();

    // Getters and setters for common attributes
    public String getTitle() {
        return title;
    }

    public void setTitle(String title) {
        this.title = title;
    }

    public String getAuthor() {
        return author;
    }

    public void setAuthor(String author) {
        this.author = author;
    }

    public int getPublicationYear() {
        return publicationYear;
    }

    public void setPublicationYear(int publicationYear) {
        this.publicationYear = publicationYear;
    }

    // Common method
    public void displayInfo() {
        System.out.println("Title: " + title);
        System.out.println("Author: " + author);
        System.out.println("Publication Year: " + publicationYear);
    }

    // Main class for testing
    public static void main(String[] args) {
        // Creating instances of different types of books
        FictionBook fictionBook = new FictionBook("The Great Gatsby", "F. Scott Fitzgerald", 1925);
        NonFictionBook nonFictionBook = new NonFictionBook("Sapiens: A Brief History of Humankind",
                "Yuval Noah Harari", 2011);
        ReferenceBook referenceBook = new ReferenceBook("The Elements of Style",
                "William Strunk Jr. and E.B. White", 1918);

        // Displaying information for each book
        System.out.println("Fiction Book:");
        fictionBook.displayInfo();
        System.out.println("Late Fee: $" + fictionBook.calculateLateFee());

        System.out.println("\nNon-Fiction Book:");
        nonFictionBook.displayInfo();
        System.out.println("Late Fee: $" + nonFictionBook.calculateLateFee());

        System.out.println("\nReference Book:");
        referenceBook.displayInfo();
        System.out.println("Late Fee: $" + referenceBook.calculateLateFee());
    }
}