/*
* Copyright (c) 1998-2011 Caucho Technology -- all rights reserved
*
* This file is part of Resin(R) Open Source
*
* Each copy or derived work must preserve the copyright notice and this
* notice unmodified.
*
* Resin Open Source is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* Resin Open Source is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE, or any warranty
* of NON-INFRINGEMENT. See the GNU General Public License for more
* details.
*
* You should have received a copy of the GNU General Public License
* along with Resin Open Source; if not, write to the
*
* Free Software Foundation, Inc.
* 59 Temple Place, Suite 330
* Boston, MA 02111-1307 USA
*
* @author Scott Ferguson
*/
package com.caucho.jms.connection;
import java.util.ArrayList;
import java.util.Enumeration;
import java.util.Iterator;
import java.util.logging.Logger;
import javax.jms.JMSException;
import javax.jms.Message;
import javax.jms.Queue;
import javax.jms.QueueBrowser;
import com.caucho.jms.JmsRuntimeException;
import com.caucho.jms.message.MessageImpl;
import com.caucho.jms.message.MessageFactory;
import com.caucho.jms.queue.AbstractQueue;
import com.caucho.jms.queue.QueueEntry;
import com.caucho.jms.selector.Selector;
import com.caucho.jms.selector.SelectorParser;
import com.caucho.util.L10N;
/**
* A basic message consumer.
*/
public class MessageBrowserImpl
implements QueueBrowser
{
static final Logger log
= Logger.getLogger(MessageBrowserImpl.class.getName());
static final L10N L = new L10N(MessageBrowserImpl.class);
private MessageFactory _messageFactory = new MessageFactory();
private JmsSession _session;
private AbstractQueue _queue;
private String _messageSelector;
private Selector _selector;
public MessageBrowserImpl(JmsSession session,
AbstractQueue queue,
String messageSelector)
throws JMSException
{
_session = session;
_queue = queue;
_messageSelector = messageSelector;
if (messageSelector != null)
_selector = new SelectorParser().parse(messageSelector);
}
public Queue getQueue()
throws JMSException
{
return _queue;
}
public String getMessageSelector()
throws JMSException
{
return _messageSelector;
}
public Enumeration getEnumeration()
throws JMSException
{
ArrayList<MessageImpl> list = new ArrayList<MessageImpl>(0);
if (_session.isActive()) {
ArrayList<QueueEntry> queueEntryList = _queue.getBrowserList();
if (queueEntryList != null) {
Iterator<QueueEntry> iterator = queueEntryList.iterator();
while (iterator.hasNext()) {
// Copying the message. So that if client actor tampers the message
// will not affect the message in the Queue.
MessageImpl messageCopy
= _messageFactory.copy((MessageImpl)iterator.next().getPayload());
list.add(messageCopy);
}
}
}
return new BrowserEnumeration(list, _selector);
}
public void close()
throws JMSException
{
}
public String toString()
{
return "MessageBrowserImpl[" + _queue + "]";
}
public static class BrowserEnumeration implements Enumeration {
private ArrayList<MessageImpl> _messages;
private Selector _selector;
private int _index;
BrowserEnumeration(ArrayList<MessageImpl> messages,
Selector selector)
{
_messages = messages;
_selector = selector;
nextValidMessage();
}
public boolean hasMoreElements()
{
return _index < _messages.size();
}
public Object nextElement()
{
if (_index < _messages.size()) {
MessageImpl msg = _messages.get(_index);
_index++;
nextValidMessage();
return msg;
}
else
return null;
}
private void nextValidMessage()
{
try {
for (; _index < _messages.size(); _index++) {
MessageImpl msg = _messages.get(_index);
if (_selector == null || _selector.isMatch(msg))
return;
}
} catch (RuntimeException e) {
throw e;
} catch (Exception e) {
throw new JmsRuntimeException(e);
}
}
}
}