Coverage Report - org.mule.transport.jms.AutoDiscoveryRedeliveryHandlerFactory
 
Classes in this File Line Coverage Branch Coverage Complexity
AutoDiscoveryRedeliveryHandlerFactory
0%
0/32
0%
0/14
0
 
 1  
 /*
 2  
  * $Id: AutoDiscoveryRedeliveryHandlerFactory.java 19191 2010-08-25 21:05:23Z tcarlson $
 3  
  * --------------------------------------------------------------------------------------
 4  
  * Copyright (c) MuleSoft, Inc.  All rights reserved.  http://www.mulesoft.com
 5  
  *
 6  
  * The software in this package is published under the terms of the CPAL v1.0
 7  
  * license, a copy of which has been included with this distribution in the
 8  
  * LICENSE.txt file.
 9  
  */
 10  
 
 11  
 package org.mule.transport.jms;
 12  
 
 13  
 import org.mule.config.i18n.CoreMessages;
 14  
 
 15  
 import java.util.Enumeration;
 16  
 import java.util.concurrent.atomic.AtomicReference;
 17  
 
 18  
 import javax.jms.ConnectionMetaData;
 19  
 import javax.jms.JMSException;
 20  
 
 21  
 import org.apache.commons.logging.Log;
 22  
 import org.apache.commons.logging.LogFactory;
 23  
 
 24  
 /**
 25  
  * This factory will consult JMS connection metadata for supported optional properties and use
 26  
  * those, if available, otherwise falling back to the manual counting of redeliveries.
 27  
  *
 28  
  * @see CountingRedeliveryHandlerFactory
 29  
  * @see org.mule.transport.jms.JmsXRedeliveryHandlerFactory
 30  
  * @see javax.jms.ConnectionMetaData
 31  
  */
 32  
 public class AutoDiscoveryRedeliveryHandlerFactory implements RedeliveryHandlerFactory
 33  
 {
 34  0
     protected final Log logger = LogFactory.getLog(getClass());
 35  
 
 36  0
     protected AtomicReference<RedeliveryHandler> delegateHandler = new AtomicReference<RedeliveryHandler>(null);
 37  
 
 38  
     protected JmsConnector connector;
 39  
 
 40  
     public AutoDiscoveryRedeliveryHandlerFactory(JmsConnector connector)
 41  0
     {
 42  0
         if (connector == null)
 43  
         {
 44  0
             throw new IllegalArgumentException(CoreMessages.objectIsNull("connector").getMessage());
 45  
         }
 46  0
         this.connector = connector;
 47  0
     }
 48  
 
 49  
     public RedeliveryHandler create()
 50  
     {
 51  
         RedeliveryHandler result;
 52  
 
 53  
         // initialize, accounting for concurrency
 54  0
         if (delegateHandler.get() == null)
 55  
         {
 56  0
             RedeliveryHandler newInstance = createInstance();
 57  0
             boolean ok = delegateHandler.compareAndSet(null, newInstance);
 58  0
             if (!ok)
 59  
             {
 60  
                 // someone was faster to initialize it, use this ref instead
 61  0
                 result = delegateHandler.get();
 62  
             }
 63  
             else
 64  
             {
 65  0
                 result = newInstance;
 66  
             }
 67  0
         }
 68  
         else
 69  
         {
 70  
             // just re-use existing handler
 71  0
             result = delegateHandler.get();
 72  
         }
 73  
 
 74  0
         return result;
 75  
     }
 76  
 
 77  
     /**
 78  
      * Create an instance using the discovery mechanism.
 79  
      *
 80  
      * @return an implementation based on the results of discovery
 81  
      */
 82  
     protected RedeliveryHandler createInstance()
 83  
     {
 84  
         RedeliveryHandler newInstance;
 85  
         try
 86  
         {
 87  0
             ConnectionMetaData metaData = connector.getConnection().getMetaData();
 88  0
             boolean supportsDeliveryCount = false;
 89  0
             final Enumeration propNames = metaData.getJMSXPropertyNames();
 90  0
             while (propNames.hasMoreElements())
 91  
             {
 92  0
                 String p = (String) propNames.nextElement();
 93  0
                 if (JmsConstants.JMS_X_DELIVERY_COUNT.equals(p))
 94  
                 {
 95  0
                     supportsDeliveryCount = true;
 96  0
                     break;
 97  
                 }
 98  0
             }
 99  
 
 100  0
             newInstance = (supportsDeliveryCount) ? new JmsXRedeliveryHandler() : new CountingRedeliveryHandler();
 101  
         }
 102  0
         catch (JMSException e)
 103  
         {
 104  
             // fallback to defaults
 105  0
             newInstance = new CountingRedeliveryHandler();
 106  0
         }
 107  
 
 108  0
         if (logger.isDebugEnabled())
 109  
         {
 110  0
             logger.debug("Using " + newInstance.getClass().getName());
 111  
         }
 112  
 
 113  0
         return newInstance;
 114  
     }
 115  
 
 116  
 }