Randomizer.random(priceMin, priceMax),
Randomizer.random(stockMin, stockMax));
List<Author> authors = Randomizer.selectRandom(allAuthors,
Math.max(1, Randomizer.random(nAuthorPerBook)));
for (Author author : authors) {
author.addBook(book);
book.addAuthor(author);
}
em.persist(book);
}