How to rollback transaction from service class? - spring

Question

I am trying to rollback for some condition by throwing exception. But i can not find proper way to do this. Here is my service class
#Service
public class UserManager implements IUserManager {
private final IBasicEM basicEM;
public ApplicantInfoManager(IBasicEM basicEM) {
this.basicEM = basicEM;
}
#Override
#TransactionAttribute(TransactionAttributeType.REQUIRES_NEW)
public boolean purgeUser(Long id) throws Exception {
//business logic
basicEM.Update(entity)
if(//condition) {
throw New RollBackException("//message")
}
//business logic
}
}
And here is my BasicEM class
#Component
#Transactional(value = "transactionManager", rollbackFor = Exception.class)
public class BasicEM {
#PersistenceContext(unitName = "db1")
private EntityManager em;
public void update(Object target) {
em.merge(target);
}
}
So what i want is to call that update method, then if the condition is true undo the update.
My intention is that when i throw the exception, the transaction ends and does not commit the update. But i am wrong and the update is already done. Please help me to achieve my goal.

Answer 1

In order to achieve what you want you will need to have a transaction already in the Service method. The default propagation type for #Transactional(value = "transactionManager", rollbackFor = Exception.class) is Propagation.REQUIRED which means that if your Service is already included in a transaction, the basicEM.Update(entity) will also be included in such transaction.
#Service
public class UserManager implements IUserManager {
private final IBasicEM basicEM;
public ApplicantInfoManager(IBasicEM basicEM) {
this.basicEM = basicEM;
}
#Override
#Transactional(value = "transactionManager",
propagation = Propagation.REQUIRES_NEW, rollbackFor = RollBackException.class)
public boolean purgeUser(Long id) throws Exception {
//business logic
basicEM.Update(entity)
if(//condition) {
throw New RollBackException("//message")
}
//business logic
}
}
If RollBackException is a RuntimeException you don't need to explicitly configure that the transaction should rollback when it is thrown. If it is not, then you need to configure it as follows: #Transactional(value = "transactionManager", propagation = Propagation.REQUIRES_NEW, rollbackFor = RollBackException.class).