我正在學(xué)習(xí) Spring JPA 和 Hibernate。所以我遇到了一個問題。我有這個方法@Transactional(isolation = Isolation.REPEATABLE_READ)public void sendMoney(Long from, Long to, Double amount) {    WalletEntity fromWallet = walletServiceImpl.getWallet(from);    WalletEntity toWallet = walletServiceImpl.getWallet(to);    fromWallet.setAmount(fromWallet.getAmount() - amount);    toWallet.setAmount(toWallet.getAmount() + amount);    TransactionEntity transaction = new TransactionEntity();    transaction.setAmount(amount);    transaction.setToWallet(toWallet);    transaction.setFromWallet(fromWallet);    transactionRepository.saveAndFlush(transaction);}我想測試它并創(chuàng)建了這個：@GetMapping("/send")public void sendMoney() {    ExecutorService executorService = Executors.newFixedThreadPool(20);    for (int i = 0; i < 100; i++) {        executorService.execute(() -> {            accountServiceImpl.sendMoney(1L, 2L, 10D);        });    }}所以當我閱讀 wallet 時，我得到了舊的價值，但我做了Isolation.REPEATABLE_READ. 數(shù)據(jù)庫中的值當然是錯誤的。你能解釋一下有什么問題嗎？謝謝！