mysql事物捕捉异常回滚_事务场景中,手动捕获异常时记得显式回滚事务
阿里巴巴《Java开发手册》:事务场景中,抛出异常被catch后,如果需要回滚,一定要手动回滚事务。
今天装了一个ali编码规约插件,在对工程做编码规约扫描时,也给出了这个提示。
汇票系统,下述发布贴现方法,要求先创建票据再创建贴现交易,整体是一个事务。如果不加异常捕获,那么一旦程序执行出现RuntimeException后,AOP捕获异常后默认会先回滚事务再throw,只不过这样对调用方(有时)不“友好”; 加了try..catch捕获到异常后,如果不显式回滚,那么,前面的“创建票据”就提交到db了,所以,为保证事务的一致性,就要手动回滚事务,并返回创单失败。
public classTradeOrderServiceImpl{
@Autowired
TradeOrderServiceImpl tradeOrderService;
@Autowired
DraftInfoServiceImpl draftInfoService;/*** 发布贴现
**/@TransactionalpublicResponseModel publish(String merId, String openBank, BigDecimal amt){
DraftInfoModel draftInfoModel= newDraftInfoModel();
draftInfoModel.setMerchantId(merId);
draftInfoModel.setAmt(amt);
... ...//创建票据
DraftInfoModel res_draftInfoModel =draftInfoService.addDraftInfo(draftInfoModel);try{
TradeOrderModel tradeOrderModel= newTradeOrderModel();
tradeOrderModel.setSellerMerchantId(merId);
tradeOrderModel.setOpenBank(openBank);//openBank超长会导致mySQL的Data truncated for column异常。
tradeOrderModel.setPlatFeeAmt(amt);
tradeOrderModel.setDraftId(res_draftInfoModel.getDraftId());
... ...//创建贴现交易
TradeOrderModelRes tradeOrderModelRes =tradeOrderService.publishDraftDiscount(tradeOrderModel);
}catch(Exception e){//手动回滚事务
TransactionAspectSupport.currentTransactionStatus().setRollbackOnly();//返回创单失败
return new ResponseModel(false, ExceptionUtils.getMessage(e));
}//返回创单完成
return new ResponseModel(true);
}
}
如下testcase作用是新增转账原因,使用@Transactional注解开启了事务,当执行第二个insert时,由于数据超长报异常:### Error updating database. Cause: com.mysql.jdbc.MysqlDataTruncation: Data truncation: Data too long for column 'transfer_reason' at row 1。此时会整体回滚事务,两个转账原因都未持久化。
@Test
@Transactionalpublic voidinsertTransferReason(){
List batchPayRecordDetails = batchPayRecordDetailMapper.selectByExample(newBatchPayRecordDetailExample());if(CollectionUtils.isEmpty(batchPayRecordDetails)){
Assert.fail("no data");
}
String auditMan="test";
BatchPayRecordDetail recordDetail=batchPayRecordDetails.get(0);
System.out.println("==============================");
recordDetail.setPayReason(UUID.randomUUID().toString());int i1 =managerBll.insertTransferReason(recordDetail, auditMan);
System.out.println(i1);
recordDetail.setPayReason(UUID.randomUUID().toString()+"测试(String), 39c535de-79ff-4fc4-a514-5c431ad4157d2019-04-04 11:26:43,147 DEBUG [main] (BaseJdbcLogger.java:145) 6219 - ==> Preparing: insert into transfer_account_reason (transfer_reason_(String), 0(String), SUCCES(String), test(String), null, null\n" +
"2019-04-04 11:28:42,975 DEBUG [main] (BaseJdbcLogger.java:145) 6611 - <== Updates: 1");int i =managerBll.insertTransferReason(recordDetail, auditMan);
System.out.println(i);
}