I am using Hibernate in my Project.
I have two methods which get called concurrently and they try to update the same rows. In the following code the two methods are updateSessionStatus() and updatePayloadTableAggregateTxtFileName().
To handle concurrent updates I am using version tag in the mapping file.
The problem is that the changes are not getting reflected in the database, whichever method last commit it's changes are getting reflected to solve this issue I am making use of version tag which is long in this case, and if there is version mismatch during update I am handling StaleStateException to merge the changes.
But it is not working and I am getting the exception as HHH000346: Error during managed flush [Batch update returned unexpected row count from update [0]; actual row count: 0; expected: 1]. Please help

public void updateSessionStatus(int jobId, String crcFileName, String crc) {
Session session = HibernateSessionFactory.getSessionFactory()
.openSession();
Transaction tx = null;
PayloadTableDao payloadTableDao = null;
try {
tx = session.beginTransaction();
Criteria crit = session.createCriteria(PayloadTableDao.class);
crit.add(Restrictions.eq("jobId", jobId));
ScrollableResults items = crit.scroll();
while (items.next()) {
payloadTableDao = (PayloadTableDao) items.get(0);
if (payloadTableDao.getError() == null) {
payloadTableDao.setCrcFileName(crcFileName);
payloadTableDao.setCrc(crc);
}
session.saveOrUpdate(payloadTableDao);

session.update(payloadTableDao);

}
tx.commit();
} catch (HibernateException asd) {
if (asd instanceof StaleStateException) {
// session.merge(payloadTableDao);
handleStale(payloadTableDao);
}
if (tx != null) {
tx.rollback();
}
LOGGER.debug(asd.getMessage());
} finally {
session.close();

}
}

public void updatePayloadTableAggregateTxtFileName(int jobId,
String txtFileName) {
Session session = HibernateSessionFactory.getSessionFactory()
.openSession();
Transaction tx = null;
PayloadTableDao payloadTableDao = null;
try {
tx = session.beginTransaction();
Criteria crit = session.createCriteria(PayloadTableDao.class);
crit.add(Restrictions.eq("jobId", jobId));
ScrollableResults items = crit.scroll();

while (items.next()) {
payloadTableDao = (PayloadTableDao) items.get(0);
if (payloadTableDao.getError() == null) {
payloadTableDao.setTxtFileName(txtFileName);
}

session.update(payloadTableDao);

}
tx.commit();
} catch (HibernateException asd) {
if (tx != null) {
tx.rollback();
}
if (asd instanceof StaleStateException) {
// session.merge(payloadTableDao);
handleStale(payloadTableDao);
}
LOGGER.debug(asd.getMessage());
} finally {
session.close();
}
}



public synchronized void handleStale(PayloadTableDao payloadTableDao) {
Session session = HibernateSessionFactory.getSessionFactory()
.openSession();
System.out
.println("***************************************************************");
Transaction tx = null;
try {
tx = session.beginTransaction();
session.merge(payloadTableDao);
tx.commit();
} catch (HibernateException e) {
LOGGER.error(e.getMessage(), e);
if (tx != null)
tx.rollback();
throw e;
} finally {
session.close();
}
}

You can use a version-less optimistic locking mechanism.

This way you can reduce the chance of getting stale state exception false positives.