Hibernate EntityInterceptor (EmptyInterceptor)：过滤掉所有@Transaction(readOnly=TRUE) 事务

Question

I defined and successfully plugged in a Hibernate DB Interceptor which catches all Transactions.

public class HibernateTransactionInterceptor extends EmptyInterceptor {

    @Override
    public void afterTransactionBegin(Transaction tx) {

        System.out.println("Intercepted"); 
        // ...
        super.afterTransactionBegin(tx);        
    }
}

applicationContext.xml:

<bean id="transactionInterceptor" class="myapp.interceptor.HibernateTransactionInterceptor" />

<bean id="sessionFactory"
        class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">
  <!-- Plug into SessionFactory the Interceptor bean define above -->
  <property name="entityInterceptor" ref="transactionInterceptor" />

  ...
</bean>

Now, the Interceptor fires on all @Transaction service methods. But I need to only intercept @Transaction(readOnly=FALSE) methods (ie, filter out all Read-Only methods). Is there a way to configure that?

Answer 1

I found the solution. There's an easy way to check for Read-Only/non-Read-Only Transactions with a Spring-level transaction listener. On the Spring level, rather than Hibernate, there's a method called TransactionSynchronizationManager.isCurrentTransactionReadOnly() . It can be called from the following implementation of TransactionSynchronization which uses a pointcut to intercept all @Before @Transactional Spring processing.

@Component
@Aspect
public class TransactionSynchronizationAspect implements TransactionSynchronization {   
    
    @Before("@annotation(org.springframework.transaction.annotation.Transactional)")
    public void registerTransactionSynchronization() {
        boolean isReadOnly = TransactionSynchronizationManager.isCurrentTransactionReadOnly();
        
        if (!isReadOnly) {
            // ... logic goes here...
        }

        // Continue
        TransactionSynchronizationManager.registerSynchronization(this);

    }

    @Override
    public void afterCompletion(int status) {
        // No custom code here
    }
}

As for the original Hibernate Transaction Listener in the Original Post, that strategy can still be used, but requires a tx:advice to restrict the Listener to specified (mapped) Service method names, like so:

<aop:config>
    <aop:advisor id="managerTx" advice-ref="txAdvice"
        pointcut="execution(* com.app.*.*.service.*.*(..))"/>
</aop:config>

<tx:advice id="txAdvice" transaction-manager="customTransactionManager">
    <tx:attributes>
        <tx:method name="delete*" propagation="REQUIRED" isolation="READ_COMMITTED"/>
        <tx:method name="update*" propagation="REQUIRED" isolation="READ_COMMITTED"/>
        <tx:method name="save*" propagation="REQUIRED" isolation="READ_COMMITTED"/>
    </tx:attributes>
</tx:advice>

This XML file can be imported with @ImportResource . With this strategy, all Write operations would be intercepted with the Listener, while Reads would always go through automatically.