public List<Transaction> toTransaction(List<TransactionDBTO> transactionDBTOs) {
    List<Transaction> transactions = new ArrayList<Transaction>();

    for (TransactionDBTO transactionDBTO : transactionDBTOs) {
      transactions.add(toTransaction(transactionDBTO));
    }
    return transactions;
  }
  public List<TransactionDBTO> toTransactionDBTO(List<Transaction> transactions) {
    List<TransactionDBTO> transactionDBTOs = new ArrayList<TransactionDBTO>();

    for (Transaction transaction : transactions) {
      transactionDBTOs.add(toTransactionDBTO(transaction));
    }
    return transactionDBTOs;
  }