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Please explain me if I understood correctly Spring documentation.

Spring docs states: https://docs.spring.io/spring/docs/current/spring-framework-reference/integration.html#jms-tx

(...)When you use the JmsTemplate in an unmanaged environment, you can specify these values (transaction and acknowledgment modes) through the use of the properties sessionTransacted and sessionAcknowledgeMode.

When you use a PlatformTransactionManager with JmsTemplate, the template is always given a transactional JMS Session.(..)

(BTW, that is true - session is transactional)

Javadoc states : https://docs.spring.io/spring-framework/docs/current/javadoc-api/org/springframework/jms/core/JmsTemplate.html

Default settings for JMS Sessions are "not transacted" and "auto-acknowledge". As defined by the Java EE specification, the transaction and acknowledgement parameters are ignored when a JMS Session is created inside an active transaction, no matter if a JTA transaction or a Spring-managed transaction.

I understood that if transaction is active, JMS Template session transaction settings are ignored - that is true - and the session should participate active transaction - that is not true.

I debug why it is not true and I found: https://github.com/spring-projects/spring-framework/blame/master/spring-jms/src/main/java/org/springframework/jms/connection/ConnectionFactoryUtils.java#L353

if (resourceHolderToUse != resourceHolder) {
  TransactionSynchronizationManager.registerSynchronization(
    new JmsResourceSynchronization(resourceHolderToUse, connectionFactory,
                             
 resourceFactory.isSynchedLocalTransactionAllowed()));
 resourceHolderToUse.setSynchronizedWithTransaction(true);
 TransactionSynchronizationManager.bindResource(connectionFactory, resourceHolderToUse);
}

The line resourceHolderToUse.setSynchronizedWithTransaction(true) is align the documentation.

The issue here: resourceFactory.isSynchedLocalTransactionAllowed()

Because resourceFactory is org.springframework.jms.core.JmsTemplate.JmsTemplateResourceFactory#isSynchedLocalTransactionAllowed which points to JmsTemplate#sessionTransacted.

Conclusion: According to documentation, if transaction is active, JmsTemplate#sessionTransacted should be ignored. But it is not true - although session is transactional, cannot not participate in commit.

JmsTemplate#sessionTransacted is finally mapped to ConnectionFactoryUtils.JmsResourceSynchronization#transacted and default=false prevents commit being called at the end of transaction (JmsResourceSynchronization "thinks" that it does not participate transaction)

Do I understand documentation right and there is really bug here?

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michaldo
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  • The name if the method says it all `isSynchedLocalTransactionAllowed` which is for local transactions (i.e the `JmsTransactionManager`) however this doesn't apply in a managed (J(2)EE) environment where the transactions are driven by JTA and not Spring (i.e. not a local transaction). – M. Deinum Oct 22 '19 at 09:34
  • @M.Deinum in my code I call `platformTransactionManager.getTransaction()` and according to "no matter if a JTA transaction or a Spring-managed transaction." I expect `sessionTransacted` should be ignored. Am I right? – michaldo Oct 22 '19 at 14:19
  • It can only participate in a transaction if it is either a native JMS transaction or a managed transaction. When it is something else like JPA it cannot participate as it isn’t able to commit and it needs to manage it itself (this is documented in the ConnectionFactoryUtils as well). – M. Deinum Oct 22 '19 at 14:43

1 Answers1

4

Guided by M. Deinum, I made more experiments and it seems I wrongly understood term Spring-managed transaction

I simply thought that Spring managed transaction is started by platformTransactionManager. But:

  1. If platformTransactionManager is JtaTransactionManager and transaction is started, it IS Spring managed transaction; JMS template attribute sessionTransacted is ignored and JMS template is part of transaction
  2. if platformTransactionManager is DataSourceTransactionManager or JpaTransactionManager then
    • if sessionTransacted is false, JMS template is not in transaction
    • if sessionTransacted is true, JMS template is synchronized with transaction: after callback/rollback on JDBC/JPA transaction correspondent commit/rollback is called on JMS transaction
michaldo
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