@Override
 // @Transactional
 public Integer update(BookView bookView)
     throws ValidationException, IllegalDatabaseStateException, ForbiddenException,
         NoSuchEntityException, AuthRequiredException {
   BookEntity bookEntity = bookCreationService.updateFields(bookView);
   return bookEntity.getId();
 }
 @Override
 @Transactional(propagation = Propagation.REQUIRED)
 public Integer update(BookEntity book)
     throws ValidationException, IllegalDatabaseStateException, ForbiddenException,
         NoSuchEntityException, AuthRequiredException {
   bookAvailabilityService.isCurrentUsersBook(book);
   BookEntity bookEntity = bookDao.update(book);
   return bookEntity.getId();
 }
 @Override
 @Transactional(propagation = Propagation.REQUIRED)
 public Integer get(String isbn) throws NoSuchEntityException, IllegalDatabaseStateException {
   BookEntity book = bookDao.getByIsbnNotNull(isbn);
   return book.getId();
 }