org.jboss.ejb.plugins.jms
Class DLQHandler

java.lang.Object
  org.jboss.mx.util.JBossNotificationBroadcasterSupport
      org.jboss.system.ServiceMBeanSupport
          org.jboss.ejb.plugins.jms.DLQHandler

All Implemented Interfaces:

javax.jms.ExceptionListener, javax.management.MBeanRegistration, javax.management.NotificationBroadcaster, javax.management.NotificationEmitter, org.jboss.system.Service, org.jboss.system.ServiceMBean

public class DLQHandler
extends org.jboss.system.ServiceMBeanSupport
implements javax.jms.ExceptionListener

Places redeliveded messages on a Dead Letter Queue.

The Dead Letter Queue handler is used to not set JBoss in an endles loop when a message is resent on and on due to transaction rollback for message receipt.

It sends message to a dead letter queue (configurable, defaults to queue/DLQ) when the message has been resent a configurable amount of times, defaults to 10.

The handler is configured through the element MDBConfig in container-invoker-conf.

The JMS property JBOSS_ORIG_DESTINATION in the resent message is set to the name of the original destination (Destination.toString()) if it is present.

The JMS property JBOSS_ORIG_MESSAGEID in the resent message is set to the id of the original message.

Version:

$Revision: 57209 $

Author:

Jason Dillon, Scott.Stark@jboss.org, Adrian Brock

Nested Class Summary

protected class

DLQHandler.DLQSynchronization Remove a redelivered message from the DLQ's buffer when it is acknowledged

Field Summary

static String	JBOSS_ORIG_DESTINATION JMS property name holding original destination.
static String	JBOSS_ORIG_MESSAGEID JMS property name holding original JMS message id.
static String	PROPERTY_DELIVERY_COUNT Standard property for delivery count

Fields inherited from class org.jboss.system.ServiceMBeanSupport

log, server, SERVICE_CONTROLLER_SIG, serviceName

Fields inherited from interface org.jboss.system.ServiceMBean

CREATE_EVENT, CREATED, DESTROY_EVENT, DESTROYED, FAILED, REGISTERED, START_EVENT, STARTED, STARTING, states, STOP_EVENT, STOPPED, STOPPING, UNREGISTERED

Constructor Summary

DLQHandler(JMSProviderAdapter providerAdapter, JMSContainerInvoker invoker)

Method Summary

protected void	createService()
protected void	deleteFromBuffer(String id) Delete the entry in the message counter buffer for specifyed JMS id.
protected void	destroyService()
boolean	handleRedeliveredMessage(javax.jms.Message msg, Transaction tx) Check if a message has been redelivered to many times.
void	importXml(Element element) Takes an MDBConfig Element
protected int	incrementResentCount(String id) Increment the counter for the specific JMS message id.
protected javax.jms.Message	makeWritable(javax.jms.Message msg, boolean trace) Make the Message properties writable.
void	onException(javax.jms.JMSException e)
protected void	sendMessage(javax.jms.Message msg) Send message to the configured dead letter queue, defaults to queue/DLQ.
protected void	startService()
protected void	stopService()
String	toString()

Methods inherited from class org.jboss.system.ServiceMBeanSupport

create, destroy, getDeploymentInfo, getLog, getName, getNextNotificationSequenceNumber, getObjectName, getServer, getServiceName, getState, getStateString, jbossInternalCreate, jbossInternalDescription, jbossInternalDestroy, jbossInternalLifecycle, jbossInternalStart, jbossInternalStop, postDeregister, postRegister, preDeregister, preRegister, start, stop

Methods inherited from class org.jboss.mx.util.JBossNotificationBroadcasterSupport

addNotificationListener, getNotificationInfo, handleNotification, nextNotificationSequenceNumber, removeNotificationListener, removeNotificationListener, sendNotification

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

PROPERTY_DELIVERY_COUNT

public static final String PROPERTY_DELIVERY_COUNT

Standard property for delivery count

See Also:

Constant Field Values

JBOSS_ORIG_DESTINATION

public static final String JBOSS_ORIG_DESTINATION

JMS property name holding original destination.

See Also:

Constant Field Values

JBOSS_ORIG_MESSAGEID

public static final String JBOSS_ORIG_MESSAGEID

JMS property name holding original JMS message id.

See Also:

Constant Field Values

Constructor Detail

DLQHandler

public DLQHandler(JMSProviderAdapter providerAdapter,
                  JMSContainerInvoker invoker)

Method Detail

onException

public void onException(javax.jms.JMSException e)

Specified by:

onException in interface javax.jms.ExceptionListener

createService

protected void createService()
                      throws Exception

Overrides:

createService in class org.jboss.system.ServiceMBeanSupport

Throws:

Exception

startService

protected void startService()
                     throws Exception

Overrides:

startService in class org.jboss.system.ServiceMBeanSupport

Throws:

Exception

stopService

protected void stopService()
                    throws Exception

Overrides:

stopService in class org.jboss.system.ServiceMBeanSupport

Throws:

Exception

destroyService

protected void destroyService()
                       throws Exception

Overrides:

destroyService in class org.jboss.system.ServiceMBeanSupport

Throws:

Exception

handleRedeliveredMessage

public boolean handleRedeliveredMessage(javax.jms.Message msg,
                                        Transaction tx)

Check if a message has been redelivered to many times. If message has been redelivered to many times, send it to the dead letter queue (default to queue/DLQ).

Returns:

true if message is handled (i.e resent), false if not.

sendMessage

protected void sendMessage(javax.jms.Message msg)
                    throws javax.jms.JMSException

Send message to the configured dead letter queue, defaults to queue/DLQ.

Throws:

javax.jms.JMSException

incrementResentCount

protected int incrementResentCount(String id)

Increment the counter for the specific JMS message id.

Returns:

the new counter value.

deleteFromBuffer

protected void deleteFromBuffer(String id)

Delete the entry in the message counter buffer for specifyed JMS id.

makeWritable

protected javax.jms.Message makeWritable(javax.jms.Message msg,
                                         boolean trace)
                                  throws javax.jms.JMSException

Make the Message properties writable.

Returns:

the writable message.

Throws:

javax.jms.JMSException

importXml

public void importXml(Element element)
               throws org.jboss.deployment.DeploymentException

Takes an MDBConfig Element

Throws:

org.jboss.deployment.DeploymentException

toString

public String toString()

Overrides:

toString in class Object