Problems with @Transactional attribute processing if mix of Spring-managed beans and load-time weaved object exists [SPR-2504]

[spring-projects-issues]

Oleksandr Alesinskyy opened SPR-2504* and commented

I have met subtle, but unpleasant bug (or rather bug family) in the transaction processing under following conditions:

I have a class annotated by @Configurable with one of methods annotated by @Transactional (import ommited for brevity).

@Configurable
public class TestAnnotations {
PlatformTransactionManager fManager;
public void setTransactionManager(PlatformTransactionManager manager) {
fManager= manager;
}
@Transactional(propagation = Propagation.REQUIRED)
public Object getTransaction() {
System.out.println("Transaction activity "+
TransactionSynchronizationManager.isActualTransactionActive());
return fManager.getTransaction(
new DefaultTransactionAttribute(
TransactionDefinition.PROPAGATION_MANDATORY
));
};
}

Objects of this class are not Spring beans but are created by "new". AspectJ load time weaving is enabled and following aop.xml is present

<!DOCTYPE aspectj PUBLIC
"-//AspectJ//DTD//EN" "http://www.eclipse.org/aspectj/dtd/aspectj.dtd">
<aspectj>
<weaver options="-showWeaveInfo -XmessageHandlerClass:org.springframework.aop.aspectj.AspectJWeaverMessageHandler">
<include within="de.ntec.feasibility.configurable.TestAnnotations"/>
</weaver>
</aspectj>
Context.xml is as follows
<?xml version="1.0" encoding="UTF-8"?>

<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:aop="http://www.springframework.org/schema/aop"
xmlns:tx="http://www.springframework.org/schema/tx"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd"

aop:spring-configured/

<!-- <tx:annotation-driven transaction-manager="txManager"/> -->

<bean id="txManager" class="org.springframework.transaction.CallCountingTransactionManager">
</bean>

<bean class="de.ntec.feasibility.configurable.TestAnnotations"
    singleton="false">
    <property name="transactionManager" ref="txManager"/>
</bean>

</beans>

(note that <tx:aspect-driven ...> is commented out, but if comments are removed, result is the same).

Java (1.5.0_08) is started with -javaagent:aspectjweaver.jar (latter resides in current directory). Weaving take place
"INFO - [AspectJ] weaving 'de/ntec/feasibility/configurable/Configurabl'"

Call

TransactionSynchronizationManager.isActualTransactionActive());

returns "true", but

fManager.getTransaction(new DefaultTransactionAttribute(TransactionDefinition.PROPAGATION_MANDATORY));

fails with exception
org.springframework.transaction.IllegalTransactionStateException: Transaction propagation 'mandatory' but no existing transaction found
at org.springframework.transaction.support.AbstractPlatformTransactionManager.getTransaction(AbstractPlatformTransactionManager.java:306)
at de.ntec.feasibility.configurable.TestAnnotations.getTransaction(Configurabl.java:29)
at de.ntec.feasibility.configurable.Main.main(Main.java:22)

So TransactionSynchronizationManager reports that transaction exists but TransactionManager is unable to found it - clear contradiction.

To finis a picture main method initializes transaction aspect in the following way

AnnotationTransactionAspect.aspectOf().setTransactionManager( (PlatformTransactionManager)(fContext.getBean("txManager")));

If I try to create as Sring-managed bean some object of a another class that has "@Transactional" annotation on one of its methods it fails as well (in different manner depending on presence of tx:annotation-driven/, presence of this class in "include" clause of aop.xml and even is this bean singleton or not. I was unable to find combination that works in presence of load-time weaving (even if wweaved classes has only @Configurable)

---

Affects: 2.0 RC3

Attachments:

• SPR-2504.zip (13.58 kB)

[spring-projects-issues]

Oleksandr Alesinskyy commented

Issue is really very subtle and very minor - error occurs if and only if some class meets ALL following conditions

1. Does not implement interface (i.e. proxied by CGLIB2-proxies)
2. Is annotated with @configurable
3. Has methods annotated with @Transactional
4. Context contains 2 bean definitions based on this class - one to be used for configuration objects of this class created by "new" operator and one to create bean by Spring (as singleton or from prototype - outcome is the same, the only differece that singleton fails on startup, and prototype on getBean call; I have not tested a case when single bean definition serves both purposes, as it is not possible with singleton).
5. AspectJ load-time weaving is enabled for this class
6. tx:annotation-driven is present

Error is as follows:

---

INFO - Destroying singletons in {org.springframework.beans.factory.support.DefaultListableBeanFactory defining beans [org.springframework.beans.factory.aspectj.AnnotationBeanConfigurerAspect,org.springframework.aop.config.internalAutoProxyCreator,org.springframework.transaction.interceptor.TransactionAttributeSourceAdvisor,txManager,dataSource,sessionFactory,de.ntec.feasibility.configurable.TestAspects,load]; root of BeanFactory hierarchy}
INFO - Closing Hibernate SessionFactory
INFO - closing
Exception in thread "main" org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'load' defined in class path resource [context2.xml]: Initialization of bean failed; nested exception is null
Caused by:

---

"Caused by" IS empty.

Sample classes, context and aop.xml are attached

[spring-projects-issues]

Oleksandr Alesinskyy commented

Files mentioned in the previous comment

[spring-projects-issues]

Adrian Colyer commented

This turned out to be an interaction between two bugs:

1. When using Spring-AOP in conjunction with AspectJ LTW, the class name seen by the @Configurable support is the CGLIB proxy classname : ....$$EnhancerByCGLIB$$...
   Since you used @Configurable with no bean name, we use the class name as the bean name, and fail to find a bean with the EnhancerByCGLIB suffix on the end. This causes
   an exception during initialization, which is reported as an AOP alliance AspectException

2. The AOPAlliance AspectException has a bug that throws an NPE when you ask for its message after constructing it with (String,Throwable). This causes us to lose the next cause
   message that Spring puts out.

I've changed the AnnotationBeanWiringInfoResolver to cope with CGLIB enhanced proxies by recognizing them as such and returning the real user type name (the superclass). This makes
your test case work again.

We should also consider patching the AOP alliance exception class to not NPE as we'll lose a lot of potential error messages otherwise... (it doesn't set the message
field that is subsequently used in getMessage()). I'll raise a separate issue for that.

[spring-projects-issues]

Adrian Colyer commented

Issue 2571 raised to cover AOPAlliance bug. This issue can now be considered fixed.

[spring-projects-issues]

Oleksandr Alesinskyy commented

Thanks