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: 5.0.0, 5.0.1, 5.0.2, 5.0.3, 5.0.4 Environment: Wildfly 8.1.0, Wildfly 8.2.0, linux, OS X Reporter: Tomasz Krakowiak Assignee: Tom Jenkinson Fix For: 5.0.5 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 `beanA.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!)