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javajakarta-eenullpointerexceptionjmsmessage-listener

JMS: Can be the message null in the onMessage of MessageListener?

is there any case where the message could be null in the Method onMessage(message), if my MessageConsumer is implementing the MessageListener (JBoss JMS 1.1 API)?

import javax.jms.MapMessage;
import javax.jms.Message;
import javax.jms.MessageListener;


@MessageDriven( ... )
public class MyMessageConsumer implements MessageListener {

    @Override
    public void onMessage(final Message message) {

      // is there any case, where message could be null here?
    }

}
Solution

  • The interface alone does not prevent that. All examples assume that the message is not null. According to http://docs.oracle.com/javaee/6/tutorial/doc/bnbpo.html:

    The onMessage method is called by the bean’s container when a message 
has arrived for the bean to service.

    In my opinion that means, that message may not be null. Even an empty message must have a message ID and a date of sending.