    @Test
    public void generatingRandomBooks_ReturnsNonEmptyBookList() {

        List<Book> books = new RandomBookGenerator().generate(15);

        assertEquals(15, books.size());

        for (Book book : books) {
            assertNotNull(book.getTitle());
            assertNotNull(book.getAuthor());
            assertNotEquals(0, book.getPublishDate().getTime());
        }
    }