事务提交的顺序正确,提交后与Spring集成挂钩

• 链包装在事务中
• JMS事务需要在数据库事务之前在链的末尾提交
• 如果JMS提交失败,则不应执行数据库提交
• 在所有成功的数据库提交之后,需要将消息(及其所有操作)放到输出通道上

问题链如下

<int:poller id="myInputChannelPoller">
  <int:transactional transaction-manager="myTransactionManager">
</int:poller>

<int:chain id="myChain" input-channel="myInputChannel">
  <int:poller ref="myInputChannelPoller" />
  <int:service-activtor id="someMessageManipulation" />
  <int:service-activtor id="aDatabaseOperation" />
  <int:service-activtor id="sendJmsMessage" />
  <int:service-activtor id="anotherMessageManipulation" />
  <int:service-activtor id="anotherDatabaseOperation" />
</int:chain>

为了在事务中包装链,我添加了 <int:transactional/> 标记投票人。

在数据库事务之前提交了所有JMS事务,我使用了 ChainedTransactionManager

@Bean
public PlatformTransactionManager myTransactionManager(JpaTransactionManager jpaTransactionManager, JmsTransactionmanager jmsTransactionManager) {
        // jpa before jms, since the commits will be done in reverse order
        return new ChainedTransactionManager(jpaTransactionManager, jmsTransactionmanager)
}

我不确定如何正确满足的唯一要求是after database commit操作。首先想到的是 transaction-synchronization-factory 机制如中所示

<int:transaction-synchronization-factory id="mySyncFactory">
  <int:after-commit channel="myOutputChannel" />
</int:transaction-synchronization-factory>

并将其链接到现有轮询器的事务

<int:poller id="myInputChannelPoller">
  <int:transactional transaction-manager="myTransactionManager" synchronization-factory="mySyncFactory">
</int:poller>

另一个想法是添加另一个 service-activator MyJpaTransactionManagerInjector MyJpaTransactionManager .

接收消息和目标输出通道作为输入。创建 ForwardMessage 然后注射到 MyJpaTransactionManager .

public class MyJpaTransactionManagerInjector {

    @Inject
    private MyJpaTransactionManager myJpaTransactionManager;

    @ServiceActivator
    public void injectMessage(Message<?> message, @Header(value = "outputChannel") MessageChannel outputChannel) {
        myJpaTransactionManager.inject(new ForwardMessage(message, outputChannel));
    }
}

登记 转发消息 在执行提交之前。

public class MyJpaTransactionManager extends JpaTransactionManager {

    private final ThreadLocal<List<TransactionSynchronizationAdapter>> synchronizations =
            new NamedThreadLocal<>("Transactional resources");

    public void inject(TransactionSynchronizationAdapter synchronization) {
        if (synchronizations.get() == null) {
            synchronizations.set(new ArrayList<>());
        }
        synchronizations.get().add(synchronization);
    }

    @Override
    protected void prepareForCommit(DefaultTransactionStatus status) {            
        super.prepareForCommit(status);
        if (synchronizations.get() != null) {
            synchronizations.get().forEach(TransactionSynchronizationManager::registerSynchronization);
        }
        synchronizations.remove();
    }
}

转发消息 afterCommit() 到目标通道

public class ForwardMessage extends TransactionSynchronizationAdapter {

    private Message<?> message;
    private MessageChannel outputChannel;

    public ForwardMessage(Message<?> message, MessageChannel outputChannel) {
        this.message = message;
        this.outputChannel = outputChannel;
    }

    @Override
    public void afterCommit() {
        outputChannel.send(message);
    }
}

只要可能,我都会避免将 TransactionManager 因为很容易破坏一些工作得很好的东西。有没有比这更好的解决方案?