java - Could not commit JPA transaction: Transaction marked as rollbackOnly

Question

I'm using Spring and Hibernate in one of the applications that I'm working on and I've got a problem with handling of transactions.

I've got a service class that loads some entities from the database, modifies some of their values and then (when everything is valid) commits these changes to the database. If the new values are invalid (which I can only check after setting them) I do not want to persist the changes. To prevent Spring/Hibernate from saving the changes I throw an exception in the method. This however results in the following error:

Could not commit JPA transaction: Transaction marked as rollbackOnly

And this is the service:

@Service
class MyService {

  @Transactional(rollbackFor = MyCustomException.class)
  public void doSth() throws MyCustomException {
    //load entities from database
    //modify some of their values
    //check if they are valid
    if(invalid) { //if they arent valid, throw an exception
      throw new MyCustomException();
    }

  }
}

And this is how I invoke it:

class ServiceUser {
  @Autowired
  private MyService myService;

  public void method() {
    try {
      myService.doSth();
    } catch (MyCustomException e) {
      // ...
    }        
  }
}

What I'd expect to happen: No changes to the database and no exception visible to the user.

What happens: No changes to the database but the app crashes with:

org.springframework.transaction.TransactionSystemException: Could not commit JPA transaction;
nested exception is javax.persistence.RollbackException: Transaction marked as rollbackOnly

It's correctly setting the transaction to rollbackOnly but why is the rollback crashing with an exception?

Answer 1

My guess is that ServiceUser.method() is itself transactional. It shouldn't be. Here's the reason why.

Here's what happens when a call is made to your ServiceUser.method() method:

1. the transactional interceptor intercepts the method call, and starts a transaction, because no transaction is already active
2. the method is called
3. the method calls MyService.doSth()
4. the transactional interceptor intercepts the method call, sees that a transaction is already active, and doesn't do anything
5. doSth() is executed and throws an exception
6. the transactional interceptor intercepts the exception, marks the transaction as rollbackOnly, and propagates the exception
7. ServiceUser.method() catches the exception and returns
8. the transactional interceptor, since it has started the transaction, tries to commit it. But Hibernate refuses to do it because the transaction is marked as rollbackOnly, so Hibernate throws an exception. The transaction interceptor signals it to the caller by throwing an exception wrapping the hibernate exception.

Now if ServiceUser.method() is not transactional, here's what happens:

1. the method is called
2. the method calls MyService.doSth()
3. the transactional interceptor intercepts the method call, sees that no transaction is already active, and thus starts a transaction
4. doSth() is executed and throws an exception
5. the transactional interceptor intercepts the exception. Since it has started the transaction, and since an exception has been thrown, it rollbacks the transaction, and propagates the exception
6. ServiceUser.method() catches the exception and returns