/*

  * Copyright (C) The Apache Software Foundation. All rights reserved.

  *

  * This software is published under the terms of the Apache Software License

  * version 1.1, a copy of which has been included with this distribution in

  * the LICENSE file.

  * 

  * $Id: XACapableAdapter.java 155459 2005-02-26 13:24:44Z dirkv $

  */

 package org.apache.commons.messenger;

 import javax.jms.Session;

 import javax.jms.XASession;

 import javax.transaction.Transaction;

 import javax.transaction.xa.XAResource;

 import org.apache.commons.logging.Log;

 import org.apache.commons.logging.LogFactory;

 /** 

  * <p><code>XACapableAdapter</code> is an adapter that implements

  * XACapable for a given Messenger 

  * </p>

  *

  * @author <a href="mailto:jstrachan@apache.org">James Strachan</a>

  * @version $Revision: 155459 $

  */

 public class XACapableAdapter implements XACapable {

     /** Logger */

     private static final Log log = LogFactory.getLog(XACapableAdapter.class);

         private Messenger messenger;

         public XACapableAdapter(Messenger messenger) {

                 this.messenger = messenger;

         }

     // XACapable interface

     //-------------------------------------------------------------------------

         public void enlistResources(Transaction transaction) throws Exception {

                 XAResource resource = getXAResource();

                 if (resource != null) {

                         transaction.enlistResource(resource);

                 }

         }

         public void delistResources(Transaction transaction, int flag) throws Exception {

                 XAResource resource = getXAResource();

                 if (resource != null) {

                         transaction.delistResource(resource, flag);

                 }

         }

     // Implementation methods

     //-------------------------------------------------------------------------

     /**

      * @return the XAResource associated with this Messenger if one exists

      */

         protected XAResource getXAResource() throws Exception {

                 Session session = messenger.getSession();

                 if (session instanceof XASession) {

                         XASession xaSession = (XASession) session;

                         return xaSession.getXAResource();

                 }

                 else {

                         log.warn(

                                 "Messenger: " + messenger 

                                 + " cannot take part in an XA transaction as it does not have an XASession."

                                 + " session: " + session 

                         );

                 }

                 return null;

         }

 }