JBossDeveloper

chapter 12.5.6 says there are 2 options as to how this can work, one of these options, option A, *doesnt* call before/afterdelivery. You can see this quite clearly on the sequence diagram figure 12-8.

we changed this so we can have more control over the transactions.

@rnicholson10 which version of the application server are you using?

Also i've just runa small test to send an object message and it worked fine for me, can you post your exatc code, MDB settings etc, so i can recreate the issue.

"ataylor" wrote:
chapter 12.5.6 says there are 2 options as to how this can work, one of these options, option A, *doesnt* call before/afterdelivery. You can see this quite clearly on the sequence diagram figure 12-8.

we changed this so we can have more control over the transactions.

" he beforeDelivery and afterDelivery method calls are considered part of
a single message delivery call. For each message delivery, the beforeDelivery,
afterDelivery methods and the actual message delivery method, must be
called from a single thread of control.

Further, the application server must set the thread context class loader to the
endpoint application class loader during the beforeDelivery call and must
reset it during a corresponding afterDelivery call. This allows a resource
adapter to use the application class loader to load application specific classes
while deserializing, or reconstructing, a message object. Note, setting of the
thread context class loader during the beforeDelivery call is independent of
whether an XAResource instance is provided by the resource adapter."

@rnicholson10 My test did send a custom object and it deserialized it fine. I'm packaging my application as an ear file with a jar inside.

@clebert.suconic@jboss.com

The bit you are mis understanding is

This allows a resource
adapter to use the application class loader to load application specific classes
while deserializing, or reconstructing, a message object. Note, setting of the
thread context class loader during the beforeDelivery call is independent of
whether an XAResource instance is provided by the resource adapter.

If i add this line of code to my onMessage method

message.getObject().getClass().getClassLoader().toString()

"rnicholson10" wrote:
I'm using JBoss-5.1.0.GA. I have no specific MDB settings, they are all contained in the MDB as annotations.

I start all MDBs with Delivery disabled. This is then enabled by another bean when it is ready to receive packets.

Note: If the object you send is a standard JDK 6 object it will work fine. It's only when you use a custom object that you get a serialization error.

My MDB (contains the workaround given by clebert):

package com.paddypower.phase.engine.bean.mdb;

import javax.ejb.ActivationConfigProperty;
import javax.ejb.MessageDriven;
import javax.jms.JMSException;
import javax.jms.Message;
import javax.jms.MessageListener;
import javax.jms.ObjectMessage;

import org.apache.log4j.Logger;

import com.paddypower.phase.common.internal.BridgeCheck;
import com.paddypower.phase.common.internal.MultiDestDataPacket;
import com.paddypower.phase.common.internal.Packet;
import com.paddypower.phase.engine.core.EngineMultiDestPacketContainer;
import com.paddypower.phase.engine.core.RoutingEngine;

@MessageDriven(
 activationConfig = {
 @ActivationConfigProperty(
 propertyName="destinationType",
 propertyValue="javax.jms.Queue"),
 @ActivationConfigProperty(
 propertyName="destination",
 propertyValue="queue/phaseQueueFromInput"),
 @ActivationConfigProperty(
 propertyName="DeliveryActive",
 propertyValue="false")
 }
)

public class EngineMDB implements MessageListener
{
 private static final Logger log = Logger.getLogger(EngineMDB.class);

 public void onMessage(Message message)
 {
 log.debug("GotMessage");

 ClassLoader original = Thread.currentThread().getContextClassLoader(); //Workaround
 try //Workaround
 { //Workaround
 Thread.currentThread().setContextClassLoader(this.getClass().getClassLoader()); //Workaround
 try
 {
 if (message instanceof ObjectMessage)
 {
 ObjectMessage msg = (ObjectMessage) message;
 Object object = msg.getObject(); //<-- Serialization error happens here

 if (object instanceof Packet)
 {
 Packet packet = (Packet) ((ObjectMessage) message).getObject();
 //... Process Packet
 }
 else
 {
 log.debug(object);
 }
 }
 else
 {
 log.debug("OTherTypeOfMessage");
 }
 }
 catch (JMSException jmse)
 {
 jmse.printStackTrace();
 }

 } //Workaround
 finally //Workaround
 { //Workaround
 Thread.currentThread().setContextClassLoader(original); //Workaround
 } //Workaround
 }
}

@ActivationConfigProperty(
 propertyName="DeliveryActive",
 propertyValue="false")

could you provide me with a full working test so that i can recreate it along with some instructions as to how you run it. you can attach it to the JIRA

System.out.println("Thread.contextClassLoader() == " + Thread.currentThread().getContextClassLoader() + " while the class " + this.getClass().getClassLoader());

 if (Thread.currentThread().getContextClassLoader() != this.getClass().getClassLoader())
 {
 System.out.println("Wrong classLoader being used!!!!");
 }

"ataylor" wrote:
@clebert.suconic@jboss.com
This is there so if the resource adapter (not the application) needs to reconstruct an object where the objects class belongs to the applications classloader. The calls will set the classloader early so we can do what we need to do before delivering the message. Since wer don't need to reconstruct the message we don't have to call it. When the onMessage is called the classloader will still be set correctly for the onMessage method.

You need the Thread Context ClassLoader (TCL) to be correct.


The TCL is not only used by us. I could list a number of useCases where the user will perform classLoader operations inside the onMessage call. Object Serialization is just one of them.

This allows a resource
adapter to use the application class loader to load application specific classes
while deserializing, or reconstructing, a message object

Andy - If this is a bug in the JBoss AS EJB3 implementation, can you add a JIRA bug report against the EJB3 project?