if (queue == null) { throw new InvalidDestinationException("Cannot create a browser with a null queue"); }
   public QueueBrowser createBrowser(Queue queue) throws JMSException   {      //As per spec. section 4.11      if (sessionType == TYPE_TOPIC_SESSION)      {         throw new IllegalStateException("Cannot create a browser on a TopicSession");      }      return createBrowser(queue, null);   }