7 Replies Latest reply on May 11, 2009 5:35 PM by Zack Radick

    ClassCastException using same jar file

    hari hari Newbie

      Hi,

      we are developing out project from 3 different eclipse projects. One is utils project which expose common.jar file. This file has simple interface that implements Serializable and class which implement :


      public interface PublishCommand extends Serializable {
       // some methods
      }
      
      public class PublishBaseCommand implements PublishCommand {
      
       private String operationType;
      
       public PublishBaseCommand() {
       }
       // some get/set methods
      }



      This will be class which will be sanded into queue1.

      Also, there is second project - Web application (on Spring) which instantiate upper class and send it to queue1. Deploy file is .war, and it contain common.jar in it's WEB-INF/lib path. Code for sending message:

      try {
       jmsDistributionTemplate.send(new MessageCreator() {
       public Message createMessage(Session session) throws JMSException {
       ObjectMessage oMessage = session.createObjectMessage();
       oMessage.setObject(new PublishBaseCommand() );
       return oMessage;
       }
       });
       }
       catch(JmsException e) {
       // ...
       }
      

      Third application is also Web application (also on Spring). This application contains listener:

      public void onMessage(Message message) {
       if (message instanceof ObjectMessage) {
       try {
       ObjectMessage objectMessage = (ObjectMessage)message;
       log.info("MSG === " + objectMessage.getObject());
       log.info("MSG HASH === " + objectMessage.getObject().getClass().hashCode());
       log.info("NED HASH === " + PublishBaseCommand.class.hashCode());
       PublishBaseCommand= (PublishBaseCommand)objectMessage.getObject();
       }
       catch(JMSException e) {
       // ...
       }
       }
       }


      main problem is in thrid application - in part where we call getObject and convert it to PublishBaseCommand - we got ClassCastException:

      [Thread-22] listener.SimpleMessageListenerContainer (AbstractMessageListenerContainer.java:634) - Execution of JMS message listener failed
      java.lang.ClassCastException: publishing.service.impl.PublishBaseCommand
       at updater.service.impl.PublishListenerImpl.onMessage(PublishListenerImpl.java:33)
       at org.springframework.jms.listener.AbstractMessageListenerContainer.doInvokeListener(AbstractMessageListenerContainer.java:531)
       at org.springframework.jms.listener.AbstractMessageListenerContainer.invokeListener(AbstractMessageListenerContainer.java:466)
       at org.springframework.jms.listener.AbstractMessageListenerContainer.doExecuteListener(AbstractMessageListenerContainer.java:435)
       at org.springframework.jms.listener.AbstractMessageListenerContainer.executeListener(AbstractMessageListenerContainer.java:407)
       at org.springframework.jms.listener.SimpleMessageListenerContainer.processMessage(SimpleMessageListenerContainer.java:290)
       at org.springframework.jms.listener.SimpleMessageListenerContainer$2.onMessage(SimpleMessageListenerContainer.java:266)
       at org.jboss.jms.client.remoting.MessageCallbackHandler.callOnMessage(MessageCallbackHandler.java:153)
       at org.jboss.jms.client.remoting.MessageCallbackHandler$ListenerRunner.run(MessageCallbackHandler.java:884)
       at EDU.oswego.cs.dl.util.concurrent.QueuedExecutor$RunLoop.run(QueuedExecutor.java:89)
       at java.lang.Thread.run(Unknown Source)


      Also following output is traced from upper log.info:


      MSG === publishing.service.impl.PublishBaseCommand@126cb1a
      MSG HASH === 13712958
      NEED HASH === 13628909



      P.S.
      I removed most of the code for readability.

      Thanks,
      Zaharije Pasalic