我有以下情况:
我在我的Affiliate
实体上进行迭代,对于每个实体,我需要在一个唯一的事务中保持并更新数据。所以我有一个带有Spring @Transactional
注释注释方法的服务(其中数据被创建和更新)但我不知道如何才能看到该事务已为联盟会员回滚?
我想知道,对于特殊的Affiliate
,事务已经回滚并从我的服务中检索自定义错误代码..
这是我使用Spring之前的服务:
public void savePostingPaymentDetails(List<Posting> postingsToUpdate, List<PaymentPostingDetail> detailsToInsert, Payment payment) {
logger.info("DB ACCESS : INSERT PAYMENT DETAILS & UPDATE POSTINGS");
long begin = System.nanoTime();
this.em.getTransaction().begin();
try {
// TEST
// 1 - Save Payments
this.em.persist(payment);
// 2 - Save Details
for (PaymentPostingDetail ppd : detailsToInsert) {
this.em.persist(ppd);
}
// 3 - Update Postings
for (Posting p : postingsToUpdate) {
if(p.getSignature() != null)
{
p.getSignature().setModification("withholding-tax.pay", new Date());
}
else
{
logger.error("The Posting with id = " + p.getIdentifier() + " has no PersistenceSignature ?!");
}
this.em.merge(p);
}
}
catch (Exception e)
{
logger.error("Unexpected error on saving/updating the DB.", e);
this.em.getTransaction().rollback();
logger.info("RollBack done.");
e.printStackTrace();
System.exit(JobStatus.ABNORMAL_END_OF_EXECUTION_ERROR.getCode());
}
this.em.getTransaction().commit();
logger.info("Details inserted & Postings updated.");
long end = System.nanoTime();
logger.info("Execution time = " + ((end-begin) / 1000000) + " milliseconds.");
logger.info("----------------------------------------------------------");
}
现在我有了这个:
@Transactional
public void savePostingPaymentDetails(List<Posting> postings, List<PaymentPostingDetail> paymentDetails, Payment payment)
{
logger.info("DB ACCESS : INSERT PAYMENT DETAILS & UPDATE POSTINGS");
long begin = System.nanoTime();
this.paymentRepository.save(payment);
this.ppdRepository.save(paymentDetails);
for(Posting p : postings){
if(p.getSignature() != null)
{
p.getSignature().setModifiedAt(LocalDate.now());
p.getSignature().setModifiedBy(PayCopyrightWithholdingTaxProcess.SIGNATURE);
}
else{
p.setSignature(new PersistenceSignature(LocalDate.now(), PayCopyrightWithholdingTaxProcess.SIGNATURE));
}
this.postingRepository.save(p);
}
long end = System.nanoTime();
logger.info("Execution time = " + ((end-begin) / 1000000) + " milliseconds.");
logger.info("----------------------------------------------------------");
}
但是,如果事务已经回滚,我怎么能返回让我们说一个特殊的整数(而不是System.exit()
)?
答案 0 :(得分:1)
您可以使用侦听器(@TransactionalEventListener
)来通知回滚事务(侦听器可以绑定到事务的不同阶段)。有关详细信息,请参阅https://docs.spring.io/spring/docs/4.2.x/spring-framework-reference/html/transaction.html的第16.8节(要求Spring&gt; = 4.2)
答案 1 :(得分:1)
有一种叫做用户管理事务(UMT)和容器管理事务(CMT)的东西
当您使用@Transactional
时,您实际上是将事务管理委派给Spring容器(CMT),后者负责为您打开和关闭事务。它
在unchecked Exception
或NullPointerException
投掷RuntimeException
时会自动回滚。用于检查
在回滚应该发生的时候必须指定的例外@Transactional(rollbackFor=myCheckedException.class)
。
您还可以监听,观察事务对TransactionalEventListener
的影响,并对某些AOP监听代码做出反应,如here所示。但是你并没有最终管理交易,Spring正在为你做。当发生特殊情况时,客户端代码无法对某些自定义代码做出反应,因为事务的管理委托给Spring。
因此,您必须回到用户管理的事务,在该事务中打开您的事务,提交它并在回滚的情况下做出反应。这正是UMT的目的:完全控制您的交易。
从你的旧代码你可能得到类似的东西:
public int savePostingPaymentDetails(List<Posting> postingsToUpdate, List<PaymentPostingDetail> detailsToInsert, Payment payment) {
int returnCode = 1 // 1 -> "success" , 0 -> "failure"
logger.info("DB ACCESS : INSERT PAYMENT DETAILS & UPDATE POSTINGS");
long begin = System.nanoTime();
long end = 0;
this.em.getTransaction().begin();
try {
// TEST
// 1 - Save Payments
this.em.persist(payment);
// 2 - Save Details
for (PaymentPostingDetail ppd : detailsToInsert) {
this.em.persist(ppd);
}
// 3 - Update Postings
for (Posting p : postingsToUpdate) {
if(p.getSignature() != null)
{
p.getSignature().setModification("withholding-tax.pay", new Date());
}
else
{
logger.error("The Posting with id = " + p.getIdentifier() + " has no PersistenceSignature ?!");
}
this.em.merge(p);
}
this.em.getTransaction().commit();
end = System.nanoTime();
}
catch (Exception e)
{
returnCode = 0;
logger.error("Unexpected error on saving/updating the DB.", e);
this.em.getTransaction().rollback();
logger.info("RollBack done.");
// e.printStackTrace();
System.exit(JobStatus.ABNORMAL_END_OF_EXECUTION_ERROR.getCode());
return returnCode;
}
//this.em.getTransaction().commit();
logger.info("Details inserted & Postings updated.");
//long end = System.nanoTime();
logger.info("Execution time = " + ((end-begin) / 1000000) + " milliseconds.");
logger.info("----------------------------------------------------------");
return returnCode = 1;
}
PS :在旁注中,最佳做法是让您在提交失败时抛出异常,而不是特殊代码。
您的新方法签名可能是:
public void savePostingPaymentDetails(List<Posting> postingsToUpdate, List<PaymentPostingDetail> detailsToInsert, Payment payment)
throws MyFailedDbOperationException, OtherException {
}
并在catch块上抛出异常
catch (Exception e)
{
logger.error("Unexpected error on saving/updating the DB.", e);
this.em.getTransaction().rollback();
logger.info("RollBack done.");
throw MyFailedDbOperationException("my db operation failed");
}