How to redirect the message to an error channel using spring integration.

[albert_newton]

I am trying to redirect my message to an error channel in the case of an exception. I have the following in my java code:

    {

        if (eventName == null)
        {
            throw new IllegalArgumentException("EventName was null");
        }

        if (eventType == null)
        {
            throw new IllegalArgumentException("EventType was null");
        }
        .
        .
        .
        .
        .

So instead of throwing an exception, I want to redirect it to an error channel.


I am using direct channels in my xml file.

In my java code I was able to do the following to send the message to a direct channel:


DirectChannel channel;
context = new ClassPathXmlApplicationContext("com.comp.asdt.audi ting/integration.xml");
channel = (DirectChannel) context.getBean("annotatorChannel");


and then do:
channel.send(MessageBuilder.withPayload(auditEvent ).build());

to send the payload.

I am trying to do something similar with the error channel namely something like:

ErrorChannel errorChannel;
errorChannel = (ErrorChannel) context.getBean("errorChannel");

and then do the following in my java code above:

{

        if (eventName == null)
        {
            errorChannel.send(MessageBuilder.withPayload(auditEvent).build());
        }

        if (eventType == null)
        {
            errorChannel.send(MessageBuilder.withPayload(auditEvent).build());
        }

However I am not able to do this. It seems that unlike DirectChannel, there is no class named ErrorChannel for me to use. Does anyone know how I can do this?

[Mark Fisher]

The simplest option is to use the MessageChannel type in your getBean call:

MessageChannel errorChannel = (MessageChannel) context.getBean("errorChannel");

Also, note that if you are using Spring 3.0+, you can avoid the cast by providing the expected type:

MessageChannel errorChannel = context.getBean("errorChannel", MessageChannel.class);

Hope that helps.
-Mark

[albert_newton]

The simplest option is to use the MessageChannel type in your getBean call:

MessageChannel errorChannel = (MessageChannel) context.getBean("errorChannel");

Also, note that if you are using Spring 3.0+, you can avoid the cast by providing the expected type:

MessageChannel errorChannel = context.getBean("errorChannel", MessageChannel.class);

Hope that helps.
-Mark

Thanks for the reply. I changed that in my java code, but seems like it is still not sending the event to my error channel. I think the problem should be in my xml file, so here's what I am doing in my xml file:

<?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:jee="http://www.springframework.org/schema/jee"
	xmlns:int="http://www.springframework.org/schema/integration"
	xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.5.xsd
	http://www.springframework.org/schema/integration http://www.springframework.org/schema/integration/spring-integration-1.0.xsd">

	<int:channel id="annotatorChannel" datatype="com.comp.asfd.auditing.auditservice.AuditEvent">
	</int:channel>
	
	<int:channel id="destinationChannel" datatype="com.comp.asdf.auditing.auditservice.AuditEvent">
	</int:channel>	
	
	<int:poller id="defaultPoller" default="true" max-messages-per-poll="10">
	    <int:interval-trigger interval="1" time-unit="SECONDS"/>
	 </int:poller>
	 
	<int:outbound-channel-adapter channel="destinationChannel" ref ="destinationAdapter" method="handleAuditEvent">
	 </int:outbound-channel-adapter>
	
	<int:transformer id="annotationTransformer" ref="annotationAdapter" input-channel="annotatorChannel" method="annotate"  output-channel="destinationChannel" />

	<bean id="annotationAdapter" class="com.comp.asdf.auditing.spring.auditservice.integration.AnnotatingTransformer">
		<property name="annotators">
			<list>
				<ref bean="angulataAnnotator" />
			</list>
		</property>
	</bean>	
		
	<bean id="destinationAdapter" class="com.comp.asdf.auditing.destination.DestinationAdapter">
		<property name="destinations">
			<list>
				<ref bean="sensageDestination" />
			</list>
		</property>
	</bean>
	
	<bean id="com.comp.asdf.auditing.auditservice.AuditService"
		class="com.comp.asdf.auditing.spring.auditservice.AuditServiceImpl">
	</bean>	
	
	
	<bean id="destinationAdapter1" class="com.comp.asdf.auditing.destination.DestinationAdapter">
		<property name="destinations">
			<list>
				<ref bean="sensageDestination" />
			</list>
		</property>
	</bean>

	
	<bean id="sensageDestination" class="com.comp.asdf.auditing.destination.SensageDestination" />
	<bean id="angulataAnnotator" class="com.comp.asdf.auditing.spring.auditservice.AngulataAnnotationEngine" />
</beans>

The way it works right now, is that the event passes from the annotator channel to the destination channel. That's all the wiring that is going on in the xml file. So that when the send method is called from one of the classes on the channel ( this is from the same class and method where I want to add the exception handling), it calls the annotator channel, which processes the event and send it to the destination channel which again processes the event using the handleAuditEvent method. Now I want to pop in the error handling code somewhere before the send is called from the java class on the annotator channel. So I put that part

 if (eventName == null)
        {
            errorChannel.send(MessageBuilder.withPayload(auditEvent).build());
        }

But I am not sure how to fit it in my xml file for this scenario. Here's what I tried to add to my xml file from above:

<int:channel id="errorChannel" datatype="com.comp.asdf.auditing.auditservice.AuditEvent">
     <int:queue capacity="500"/>
 </int:channel>

<int:chain input-channel="errorChannel" >
   <int:header-enricher error-channel="errorChannel"/>
   <int:service-activator ref = "com.comp.asdf.auditing.auditservice.AuditService" method="log"/>
</int:chain>

where log is the method where my exception statements are. This does not seem to be writing the error events to the errorChannel, so either I have the error channel configured wrong or I am missing something in my xml file, but not sure.

[oleg.zhurakousky]

Can you verify that the following method is invoked:

...
errorChannel.send(MessageBuilder.withPayload(auditEvent).build());
...

Can you put a log statement there?

[albert_newton]

Can you verify that the following method is invoked:

...
errorChannel.send(MessageBuilder.withPayload(auditEvent).build());
...

Can you put a log statement there?

I put a system.out in that section, but it is not even reaching that part, when I run my junit. It actually errors out while loading the bean definition from the xml file. It gives an out of memory error for the Java heap space, and seems like it is actually erroring out while loading the error Channel beans or something associated with it, like the selector or so. Here is the stack trace:

org.springframework.integration.scheduling.SimpleTaskScheduler destroy
INFO: shutting down TaskExecutor
Jun 16, 2010 9:29:51 AM org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor shutdown
INFO: Shutting down ThreadPoolExecutor
Jun 16, 2010 9:29:51 AM org.springframework.beans.factory.support.DefaultSingletonBeanRegistry destroySingletons
INFO: Destroying singletons in org.springframework.beans.factory.support.DefaultListableBeanFactory@1549f94: defining beans [errorChannel,org.springframework.integration.channel.MessagePublishingErrorHandler#0,taskScheduler,org.springframework.integration.selector.PayloadTypeSelector#0,org.springframework.integration.channel.interceptor.MessageSelectingInterceptor#0,annotatorChannel,org.springframework.integration.selector.PayloadTypeSelector#1,org.springframework.integration.channel.interceptor.MessageSelectingInterceptor#1,destinationChannel,org.springframework.integration.selector.PayloadTypeSelector#2,org.springframework.integration.channel.interceptor.MessageSelectingInterceptor#2,org.springframework.integration.scheduling.IntervalTrigger#0,defaultPoller,org.springframework.integration.handler.MethodInvokingMessageHandler#0,org.springframework.integration.config.ConsumerEndpointFactoryBean#0,org.springframework.integration.transformer.MethodInvokingTransformer#0,org.springframework.integration.transformer.MessageTransformingHandler#0,annotationTransformer,org.springframework.integration.transformer.HeaderEnricher#0,org.springframework.integration.transformer.MessageTransformingHandler#1,org.springframework.integration.handler.ServiceActivatingHandler#0,annotationAdapter,destinationAdapter,com.comp.asdf.auditing.auditservice.AuditService,destinationAdapter1,persistenceInterceptor,sensageDestination,angulataAnnotator]; root of factory hierarchy
Jun 16, 2010 9:29:51 AM org.springframework.integration.scheduling.SimpleTaskScheduler destroy
INFO: shutting down TaskExecutor
Jun 16, 2010 9:29:51 AM org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor shutdown
INFO: Shutting down ThreadPoolExecutor
java.lang.OutOfMemoryError: Java heap space
	at java.lang.AbstractStringBuilder.expandCapacity(AbstractStringBuilder.java:99)
	at java.lang.AbstractStringBuilder.append(AbstractStringBuilder.java:393)
	at java.lang.StringBuffer.append(StringBuffer.java:225)
	at java.io.StringWriter.write(StringWriter.java:90)
	at java.io.PrintWriter.write(PrintWriter.java:384)
	at java.io.PrintWriter.write(PrintWriter.java:401)
	at java.io.PrintWriter.print(PrintWriter.java:532)
	at java.io.PrintWriter.println(PrintWriter.java:669)
	at java.lang.Throwable.printStackTraceAsCause(Throwable.java:539)
	at java.lang.Throwable.printStackTraceAsCause(Throwable.java:546)
	at java.lang.Throwable.printStackTraceAsCause(Throwable.java:546)
	at java.lang.Throwable.printStackTraceAsCause(Throwable.java:546)
	at java.lang.Throwable.printStackTraceAsCause(Throwable.java:546)
	                                  .
                                          .
                                          .
                                          .

So seems like something regarding the error Channel is configured incorrectly.

[oleg.zhurakousky]

Can you please provide a minimal configuration that replicates the problem. The exception you are showing could be caused by any bean within your configuration