Question

I have a book class, then a novel- and a science book class that extend the book class.

I made an ArrayList using the book class, then inserted the novels and the science books into that. Now I’m trying to iterate through the ArrayList to count how many novels are there. How can I tell?

Would love to see some examples of this! I’ve been at it for a while.

Answer 1

You can use instanceof to check the real type of an object:

List<Book> books = new ArrayList<Book>();
books.add(aNovel);
books.add(aScienceBook);

int novelCount = 0;

for (Book book : books) {
    if (book instanceof Novel)
        novelCount++;
}