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For spring-batch transaction is not getting rolled back after exception

I am working on a spring-batch, where after reader and processor, writer is responsible to populate data to DB. Writer is calling Service which internally calls DAO layer. In method insertToDB() if some exception occurs the transaction is not being rolled back. PSB my code.
public class MyWriter{
#Autowired
private MyService myService;
#Override
public void write(List<? extends MyBO> list) {
try{
for(MyBO bo: list){
myService.insert(bo);
}
}
catch(Exception e){
log.error("Cant write to DB")
}
}
public class MyService{
#Autowired
private TableOneDAO tableOneDao;
#Autowired
private TableTwoDAO tableTwoDAO;
#Autowired
private TableThreeDAO tableThreeDAO;
public void insert(MyBO bo){
try{
// do other stuff of processing bo and create entity
MyEntityTableOne myentity1 = getEntityT1(bo);
MyEntityTableTwo myentity2 = getEntityT2(bo);
MyEntityTableThree myentity3 = getEntityT3(bo);
insertToDB(myEntity1,myEntity2,myEntity3);
}
catch(Exception e){
log.error("Error occured.");
throw new MyException("Error Blah blah occured");
}
}
#Transactional(value = "txn1")
public void insertToDB(MyEntityTableOne entity1, MyEntityTableTwo entity2, MyEntityTableThree entity3) {
try{
tableOneDao.insert(entity1);
tableTwoDAO.insert(entity2);
tableThreeDAO.insert(entity3);
}
catch(Exception e){
log.error("Error occured during insert to DB");
throw new MyException("Error Blah blah occured during DB insert");
}
}
The code goes to the catch block, but doesn't rollback records. If some error occurs during insert of Table2 then entry for Table1 is not rolled-back. And if occurs during table3 insertion then table1 and table2 records are not rolled-back.
If I move the #Transactional annotation to insert() method it works fine. What is root cause of this issue. What I have to do if I want to have transaction only on insertToDB() method.

I am trying to make it simple: To support #Transactional spring wraps the implementing class into a so called proxy and surrounds the method call / class with the transactional logic.
Now you are calling the #Transactional annotated method within the same class. Therefore the proxy is not invoked and the transactional does not work. When moving the annotation to your insert method you are invoking the method from outside of the class which means you invoke the method against the proxy.
Thats a limitation of Spring AOP (?) I think.
You can do something like following to achieve what you want:
public class MyService{
#Ressource
private MyService self;
...
self.insertToDB(myEntity1,myEntity2,myEntity3)

Your item writer will be already called in a transaction driven by Spring Batch and that you can configure at the step level by providing the transaction manager and transaction attributes. So there is no need to use #Transactional in the downstream service used by the writer.
You need to remove that annotation from MyService and it should work as expected.

Transactional Method not rolling back for unchecked Exception

#Service
public class TransactionClass{
#AutoWire
TransactionClass tranClass;
#Autowire
TransactionRepository transRepo;
public void methodA(Data data){
try{
methodB(data)
}catch(Exception e){
//some logic
}
}
public void methodB(Data data){
//some logic
tranClass.methodC(data)
}
#Transactional
public void methodC(Data data){
//some logic
transRepo.save(data);
throw new RuntimeException();
}
}
The problem is that the methodC() isn't getting rolled back even though an unchecked exception is thrown.

To check how transactions work using logs, just add this to the application.yaml
logging.level.org.springframework.transaction.interceptor: TRACE
logging.level.org.springframework.orm.jpa.JpaTransactionManager: DEBUG
logging.level.org.hibernate.SQL: DEBUG
spring.jpa.properties.hibernate.use_sql_comments: true

Transactional Method not rolling back as it had multi DB connection. So #Transactional will roll back for the only primary configuration and we can have only one primary configuration as well in an application. The solution to this is to use a chained transaction.
Refer to this link for furthermore on the chained transaction:
https://blog.usejournal.com/springboot-jpa-rollback-transaction-with-multi-databases-53e6f2f143d6

How to rollback transaction on calling #Transactional and non-Transactional method in same and different Service?

I am using spring data rest and Spring JPA. I am having one method which update one database table.
#Autowired InvoiceClient;
#Override
#Transactional
public String doBilling(String x){
//get date from TableOne
Bill bill = billsRepository.getBill(x);
if(bill.isPaid()){
generateInvoice();
}
bill.setPaymentDate(new Date());
return "SUCCESS";
}
generateInvoice is non Transactional method which calls #Transactional method from other service.
public void generateInvoice(){
invoiceClient.generateInvoice();//this is #Transactional, make changes in TableTwo
}
In case of any exception in generateInvoice method whole transaction is rolled back.
Now I want to add one more method which will have list of bill numbers. I call doBilling method in loop to do billing for all the bills.
#Override
#Transactional(readOnly = false, rollbackFor = {Throwable.class}, propagation = Propagation.REQUIRED)
public String doBillingForAll(List<String> tx){
for(String x: tx){
doBilling(x);
}
}
But now in case of any exceptions in doBilling method, all the setPayment methods are getting rolled back but generateInvoice is persisted.
I want to rollback generateInvoice also. How can I do it?

You don't need to define a rollbackFor = {Throwable.class}.
By default all RuntimeException do a rollback when using #Transactional.
It can be that because you are using and intermediate non #Transactional annotated method, the main Transaction is suspended and a nested one is created.
Try to put #Transactional in your public void generateInvoice() then Propagation.REQUIRED should be applied with rollback of your invoices

Best practices with EJB [duplicate]

This question already has answers here:
Letting the presentation layer (JSF) handle business exceptions from service layer (EJB)
(1 answer)
Handling service layer exception in Java EE frontend method
(3 answers)
Closed 5 years ago.
Recently, I've decided to use EJB in my project. Basically, are Stateless EJBs in order to make the business layer and persist data. I'm also using container managed transactions (CMT) and everything works fine.
I tried to handle the exceptions in EJB service methods in order to get the more specific exceptions and give specific errors messages to the client.
#Stateless
public class EJBService {
#PersistenceContext(unitName="PU")
private EntityManager em;
public void save(Animal a) throws AppException
{
try
{
em.persist(e);
}
catch(ConstraintViolationException ex)
{
throw new AppException("message");
}
catch(Exception ex)
{
throw new AppException("message 1");
}
}
}
The AppException extends Exception and is marked with the annotation #ApplicationException(rollback=true)
However, I can't handle the exception before the method commit the transaction. If something goes wrong the transactions are not commited (OK), but I don't have the specific exception, only javax.ejb.EJBTransactionRolledbackException: Transaction rolled back. I could use the flush method after try to persist or merge, but it isn't seems right.
So, I've decided don't try to handle the exceptions in EJB service layer leaving my methods like this:
#Stateless
public class EJBService {
#PersistenceContext(unitName="PU")
private EntityManager em;
public void save(Animal a)
{
em.persist(a);
}
and the client (A managed bean, for example), like this:
#Named
#RequestScoped
public class Bean {
private Animal animal;
#Inject
private EJBService service;
public void save() {
try
{
service.save(animal);
}
catch(Exception e)
{
//Unwrapping the exception in order to pass the
//appropriate message
}
}
}
In order to show the right messages, the method who invoked the ejb service must to handle the exception by itself, unwrapping the exception.
The question is: Am I right ? If I'm not, what is the best way to handle exceptions ?

Hibernate/Spring - Rollback a transaction within a transaction

Given this example code:
public class MyServiceImpl implements MyService {
#Transactional
public void myTransactionalMethod() {
List<Item> itemList = itemService.findItems();
for (Item anItem : itemList) {
try {
processItem(anItem);
catch (Exception e) {
// dont rollback here
// rollback just one item
}
}
}
#Transactional
public void processItem(Item anItem) {
anItem.setSomething(new Something);
anItem.applyBehaviour();
itemService.save(anItem);
}
}
Here is what I want to achieve:
Only processItem(anItem); should rollback if exception occurs inside it.
If exception occurs, myTransactionalMethod should continue, that means the for-each should end.
If exception occurs inside myTransactionalMethod but not in processItem(anItem), myTransactionalMethod should rollback completely.
Is there a solution that doesn't involve managing transactions manually (without annotations)?.
Edit: I was thinking of using #Transactional(PROPAGATION=REQUIRES_NEW), don't know if it will work within the same bean though.

This is a common misunderstanding. Spring Transactions are implemented through proxies. Proxies are a wrapper around your class. You are accessing the processItem method from the same class, i.e. you don't go through the proxy, so you don't get any transactions. I explained the mechanism in this answer some years ago.
Solution: you need two separate Spring beans if you want nested transactions, both of them must be proxied by #Transactional.

It looks like a case for NESTED transaction. NESTED transaction starts a subtransaction with in the outer transaction with savepoint, allowing it rollback to that savepoint. Since it is a nested transactions they committed at the end of outer transation.
public class MyServiceImpl implements MyService {
#Transactional
public void myTransactionalMethod() {
List<Item> itemList = itemService.findItems();
for (Item anItem : itemList) {
try {
// If you want to call this method directly configure your transaction use to aspectJ for transaction handling or refactor the code. Refer - [http://stackoverflow.com/questions/3423972/spring-transaction-method-call-by-the-method-within-the-same-class-does-not-wo][1]
processItem(anItem);
catch (Exception e) {
// dont rollback here
// rollback just one item
}
}
}
#Transactional(PROPAGATION = PROPAGATION.NESTED)
// Throw some runtime exception to rollback or some checkedException with rollbackFor attribute set in the above annotation
public void processItem(Item anItem) {
anItem.setSomething(new Something);
anItem.applyBehaviour();
itemService.save(anItem);
}
}
Note that, I have not yet tried this below code see if that helps. You might have to tweak it, if needed. In fact I would love to give this code a try myself sometime soon.