Enumeration Interface - Iterate backwards, Getting the size, Start iterating at a certain point

I have had this issue for a while now, and I'm hoping that someone can help me with this. I have a java class that connects to a queue using the jmx QueueBrowser api. I used its getEnumeration() method in order to iterate through the messages on a Weblogic queue as this is the only way that is provided. The messages are returned in the way a queue works (FIFO).

Questions:
--------------------
1. Is there a way to iterate through this Enumeration starting from the last message on published to the queue, essentially working with it as if it were a stack and not a queue?

2. Is there a way to get the total size of the Enumeration without first converting it to a Collection? Note: I tried the code below and it killed the performance of my application to the point where it was not usable (takes an extremely long time to do this conversion).

List<BrowserVO> messagesList = Collections.list(queueBrowser.getEnumeration());
int total = messagesList.size();

3. Is there a way to start iterating through an Enumeration at a certain spot (not at the first element)? I tried to convert it to a collection first, but performance is a major issue (see #2 above). I'd like to be able to return messages 1-50 to the caller, and then 51-100, and so on based on the caller's request. Right now, I can only return the first n items and that's it.

Thanks again.

private static final String JNDI_FACTORY = "weblogic.jndi.WLInitialContextFactory";
	private static final String JDBC_DRIVER_CLASS_NAME = "oracle.jdbc.driver.OracleDriver";
	private int numMsgs;
	private int totalMsgs;
	
	@SuppressWarnings({ "rawtypes", "unchecked" })
	public ArrayList browseJmsQueue(String server, String queueName,String connectionFactoryName,String user,String pass) throws Exception
	{
		
		ArrayList list = new ArrayList();
		numMsgs = 0;
		
	 	
	 	try
	 	{
	 		Hashtable env = new Hashtable();
	        env.put(Context.INITIAL_CONTEXT_FACTORY, JNDI_FACTORY);
	        env.put(Context.PROVIDER_URL, server);
	        InitialContext ctx1 = new InitialContext(env);
		 	Queue queue = (Queue) ctx1.lookup(queueName);
		 	QueueConnectionFactory connFactory = (QueueConnectionFactory) ctx1.lookup(connectionFactoryName);
		 	QueueConnection queueConn = connFactory.createQueueConnection(user,pass);
		 	QueueSession queueSession = queueConn.createQueueSession(false,Session.AUTO_ACKNOWLEDGE);
		 	QueueBrowser queueBrowser = queueSession.createBrowser(queue);
		 	queueConn.start();
		 	
			Enumeration<BrowserVO> e = queueBrowser.getEnumeration();
			
			//List<BrowserVO> messages = Collections.list(queueBrowser.getEnumeration());
			//ArrayList <BrowserVO>aList = Collections.list(e);
			//Iterator iterator = IteratorUtils.asIterator(e);
			//ListIterator listIterator = IteratorUtils.singletonListIterator(iterator);
			
			
			
			BrowserVO valueObj = null;
			while (e.hasMoreElements() && numMsgs<50) 
			{
				Message message = (Message) e.nextElement();
				numMsgs++;
				
				String messageStr = ((TextMessage)message).getText();
				
				try
				{
					valueObj = new BrowserVO();
					valueObj.setMessage(messageStr);
					
					list.add(valueObj);
				}
				catch(Exception e1)
				{
					//Ignore the messages that don't fit the type I am looking for
				}
			}
			
			System.out.println("Total Messages: "+numMsgs);
			
			queueConn.close();
        }
       
	 	catch(Exception e)
	 	{
	 		throw new QueueBrowserException(e.toString());
	 	}
	 	
		return list;
	}

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