Hello Everybody,
I found that if I change in my bean:
from:
System.out.println(" received message. returning error.");
exchange.setStatus(ExchangeStatus.ERROR);
channel.send(exchange);
to:
System.out.println(" received message. returning error.");
throw new MessagingException(" ALWAYS RETURN ERROR. throw messaging
exception.");
camel is catching the error correctly and making redeliveries and sending to
deadletter endpoint.
I searched on the documentation and google, but didn't find the response; my
question is: what is the difference between returning an error exchange and
throw an exception? which is the recommended way of handling errors in bean?
and
what about patterns on error handling on servicemix?
Thank you very much.
Regards.
Javier.
________________________________
From: Javier Arias <[email protected]>
To: [email protected]
Sent: Thu, July 8, 2010 12:54:22 PM
Subject: Camel dealetter + Bean strange behaviour
Hello All,
Our general error policy for some parts of our processes is to use a camel
deadletter queue (on file).
What I am trying to do is (sm 3.3.1)
FILE POLLER => CAMEL DEADLETTER => BEAN
In case of error CAMEL would send to a file sender.
So, in an SA we have a bean that make some actions and return DONE or ERROR
depending on the result, what I would expect is that if the bean returns ERROR
camel retries for a number of times and sends to the deadletter, but this is
not
done. It is not retrying or sending to deadletter, and my msg disappears (msg
comes from a file poller).
>From other part of the process we are sending an email, which works perfectly
with camel deadletter, retrying and sending to deadletter when necessary.
Probably I am doing wrong but I do not know what.
Below is an example (also, I attached my sample SA):
Thank you in advance.
Javier
====================================================================
BEAN :::
====================================================================
package playground.bean;
import javax.annotation.Resource;
import javax.jbi.messaging.DeliveryChannel;
import javax.jbi.messaging.ExchangeStatus;
import javax.jbi.messaging.MessageExchange;
import javax.jbi.messaging.MessagingException;
import org.apache.servicemix.jbi.listener.MessageExchangeListener;
public class AlwaysErrorBean implements MessageExchangeListener {
@Resource
private DeliveryChannel channel;
@Override
public void onMessageExchange(MessageExchange exchange) throws
MessagingException {
if (exchange.getStatus() != ExchangeStatus.ACTIVE) {
System.out.println("onMessageExchange : RECEIVED NON ACTIVE
EXCHANGE
: " + exchange.getStatus().toString());
return;
}
System.out.println(" received message. returning error.");
exchange.setStatus(ExchangeStatus.ERROR);
channel.send(exchange);
}
}
====================================================================
CAMEL ROUTE :::
====================================================================
package playground.camel;
import org.apache.camel.Exchange;
import org.apache.camel.Processor;
import org.apache.camel.builder.RouteBuilder;
import org.apache.camel.model.InterceptorType;
import org.apache.camel.processor.DelegateProcessor;
public class CamelRouteBuilder extends RouteBuilder {
private final static String JBI_ENDP = "jbi:endpoint:";
private final static String NAMESPACE = "http://playground";;
public void configure() throws Exception {
DelegateProcessor proc = new DelegateProcessor(){
public void process(Exchange exchange) throws Exception {
System.out.println(exchange.toString());
processNext(exchange);
}
protected void processNext(Exchange exchange) throws
Exception {
if (processor != null) {
processor.process(exchange);
}
}
};
// ALTERNATIVE 1 : SEND TO ALWAYSERROR BEAN
from(JBI_ENDP+NAMESPACE+"/camelDeadLetter/camelDeadLetterEp")
.errorHandler(deadLetterChannel(JBI_ENDP+NAMESPACE+"/deadLetter/deadLetterEp"))
.to(JBI_ENDP+NAMESPACE+"/alwaysErrorBean/alwaysErrorBeanEp").addInterceptor(proc);
// ALTERNATIVE 2 : SEND TO MAIL COMPONENT
// from(JBI_ENDP+NAMESPACE+"/camelDeadLetter/camelDeadLetterEp")
//
.errorHandler(deadLetterChannel(JBI_ENDP+NAMESPACE+"/deadLetter/deadLetterEp"))
//
.to(JBI_ENDP+NAMESPACE+"/emailSender/emailSenderEp").addInterceptor(proc);
}
}
