Iterator迭代器导致java.util.NoSuchElementException

多次iterator.next()导致迭代器越界，应该先取出来，再判断

Iterator<DownUrlEntity> iterator = req.iterator();
        while (iterator.hasNext()){
            if (iterator.next().getId() == null) {
                if (!"".equals(iterator.next().getCode())  && !"".equals(iterator.next().getUrl())) {
                    iterator.next().setCreateTime(new Date());
                    if (downUrlService.save(iterator.next())) {
                        iterator.remove();
                    }
                }
            }
        }