How to add logging to a jdbc pollar adapter

Question

I am trying to implement BeanPostProcessor to return my own JdbcPollingChannelAdapter that will help me to add some logging and know about polling activity. I have some code below, please help to complete this or if there is a better way.

Thanks

public class CustomAdapter extends JdbcPollingChannelAdapter {

private final static Logger logger = LoggerFactory.getLogger(CustomAdapter .class);

public CustomJdbcPollingChannelAdapter(DataSource dataSource, String selectQuery)
{
    super(dataSource, selectQuery);        
}

@Override
public Message<Object> receive()
{
    Message<Object> polledData =  super.receive();
    if(polledData == null || polledData.getPayload() == null)
    logger.info("received no data..............");
    return polledData;

}

}

public class MyPostProcessor implements BeanPostProcessor {

private final static Logger logger = LoggerFactory.getLogger(MyPostProcessor .class);

public Object postProcessAfterInitialization(Object bean, String beanName)throws BeansException
{
    /* not able to figure what goes here for this to work.
    logger.info(bean+"..................."+beanName);
    if(bean instanceof org.springframework.integration.config.SourcePollingChannelAdapterFactoryBean)
    {
        //SourcePollingChannelAdapterFactoryBean bean = (SourcePollingChannelAdapterFactoryBean)bean;
        //bean...??
        return bean;
    }
    else
    {
     return bean;
    }
    */
    return bean;
}


public Object postProcessBeforeInitialization(Object bean, String beanName)throws BeansException
{
    //logger.info(bean+"................................................."+beanName);
    return bean;
}

}

Answer 1

The JdbcPollingChannelAdapter is a MessageSource<?> and it is a component to be used from active endpoint - SourcePollingChannelAdapter, which has this code:

if (message == null) {
    if (this.logger.isDebugEnabled()){
        this.logger.debug("Received no Message during the poll, returning 'false'");
    }
    result = false;
}
else {
    if (this.logger.isDebugEnabled()){
            this.logger.debug("Poll resulted in Message: " + message);
    }
    if (holder != null) {
        holder.setMessage(message);
    }
    this.handleMessage(message);
    result = true;
}

So, isn't it enough for you to just configure org.springframework.integration.endpoint.SourcePollingChannelAdapter logging category?

From other side, there are no stops to use your custom MessageSource<?> implementation and BeanPostProcessor is really an overhead. You just need to configure your CustomAdapter as a generic <bean> and use it from another generic bean definition - SourcePollingChannelAdapterFactoryBean.

Right, with that customization you lose the Spring Integration XML power. But who said that XML is a panacea - Spring Integration Java DSL?

UPDATE

Since you have a custom MessageSource<?> you can use it directly from:

<bean id="jdbcSource" class="com.my.proj.adapter.CustomAdapter">
   <constructor-arg ref="dataSource"/>
   <constructor-arg value="SELECT * FROM foo"/>
   <property name="updateSql" value="UPDATE foo set status=1 where id in (:id)"/>
</bean>

<int:inbound-channel-adapter ref="jdbcSource" channel="jdbcPollingChannel"/>

Any protocol-specific <*:inbound-channel-adapter> is just for convenience, but they all do them same as default one.