EJB TransactionAttribute(TransactionAttributeType.REQUIRES_NEW) doesn'

Question

I encountered an odd EJB transaction attribute problem. The @TransactionAttribute(TransactionAttributeType.REQUIRES_NEW) doesn't start a new transaction as expected.

I am using EJB 3 with Weblogic.

Here is the pseudo code:

@Stateless
public class EJB1 implements IEJB1
{
   @EJB 
   private IEJB2 ejb2;

   @Override
   public void method1()
   {
     for (i=0; i<N; i++) {
         ejb2.method2();
      }
   }
}

@Stateless
public class EJB2 implements IEJB2
{
   @TransactionAttribute(TransactionAttributeType.REQUIRES_NEW)
   public void method2()
   {
     DBpersist();
   }
}

Since I specified TransactionAttributeType.REQUIRES_NEW for EJB2.method2, I expect a new transaction to be created for methood2. But during testing I found out there's no new transaction created for method2, instead method2 has the same transaction as EJB1.method1. I used Weblogic's API to log the transaction info.

I then made the following code change:

@Override
@TransactionAttribute(TransactionAttributeType.NOT_SUPPORTED
public void method1()
{    
    for (i=0; i<N; i++) {
    ejb2.method2();
    }
}

This way it forced the container to create a new transaction for EJB2.method2.

But I don't understand why the container didn't create new transaction for EJB2.method2 when I had default TransactionAttributeType for EJB1.method1 (by not specifying any TransactionAttributeType) and TransactionAttributeType=REQUIRES_NEW for EJB2.method2.

I searched the existing questions related to this question. But all I found were the cases when you call a private method(with REQUIRES_NEW) from another private method within the same EJB, the container won't start a new transaction unless you call it through the EJB interface. This is not my case.

Hi Michael, you mean to provide the example code that can be compiled? — user2984046
As NOT_SUPPORTED "helped" to actually force the creation of a new transactions also means that there actually was a running transaction already (perhaps created by an EJB Client). Are you sure you didn't accidentally measure this one as used of the whole time? — Big Bad Baerni

aschoerk aschoerk · Accepted Answer · 2017-08-26T05:23:26

The pseudo code looks ok. This has been practiced by me in various projects so there is nothing wrong.

There might be various causes for this

Bug in the used weblogic version either in the interpretation of the transactionattribute inside REQUIRES or when injecting @EJB
Bug in usage of the transaction info api

EJB TransactionAttribute(TransactionAttributeType.REQUIRES_NEW) doesn'

1 Answers