[jbossts-issues] [JBoss JIRA] (JBTM-2350) CDI Transactional interceptors are not thread safe. (previousUserTransactionAvailability)

[Tomasz Krakowiak (JIRA)]

Tomasz Krakowiak created JBTM-2350:
--------------------------------------

             Summary: CDI Transactional interceptors are not thread safe. (previousUserTransactionAvailability)
                 Key: JBTM-2350
                 URL: https://issues.jboss.org/browse/JBTM-2350
             Project: JBoss Transaction Manager
          Issue Type: Bug
          Components: JTA
    Affects Versions: 5.0.4, 5.0.3, 5.0.2, 5.0.1, 5.0.0
         Environment: Wildfly 8.1.0, Wildfly 8.2.0, linux, OS X
            Reporter: Tomasz Krakowiak
            Assignee: Tom Jenkinson


The problem is with availability of `UserTransaction`.

Availability of UserTransaction is stored in `ServerVMClientUserTransaction.isAvailables` which is `ThreadLocal<Boolean>`.

`TransactionalInterceptorRequired` when intercepting call, stores thread local value of `isAvailables` in `TransactionalInterceptorBase.previousUserTransactionAvailability` field of interceptor - which is of type boolean(not thread local).


Here's a story:
We have a bean (beanA) with single method annotated transactional (beanA.transactional()).
This method is being called from two threads, where:
 - Thread 1 is participating in BMT, therefore it's ServerVMClientUserTransaction.isAvailables value is true.
 - Thread 2 is participating in CMT, therefore it's ServerVMClientUserTransaction.isAvailables value is false.
Both threads call beanA.transactional() at the same time.

What may happen:
 1. Thread 1 - enters method beanA.transactional.
     Interceptor sets previousUserTransactionAvailability to true.
 2. Thread 2 - enters method beanB.transactional.
     Interceptor sets previousUserTransactionAvailability to false.
 3. Thread 1 - exits method beanA.transactional
     Interceptor restores thread local value of `isAvailables` to false (leaked value from thread 2!)






--
This message was sent by Atlassian JIRA
(v6.3.11#6341)