Coverage Report - org.mule.umo.FutureMessageResult
 
Classes in this File Line Coverage Branch Coverage Complexity
FutureMessageResult
0%
0/29
0%
0/4
2
 
 1  
 /*
 2  
  * $Id: FutureMessageResult.java 7976 2007-08-21 14:26:13Z dirk.olmes $
 3  
  * --------------------------------------------------------------------------------------
 4  
  * Copyright (c) MuleSource, Inc.  All rights reserved.  http://www.mulesource.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.umo;
 12  
 
 13  
 import org.mule.impl.MuleMessage;
 14  
 import org.mule.umo.transformer.TransformerException;
 15  
 import org.mule.umo.transformer.UMOTransformer;
 16  
 import org.mule.util.concurrent.DaemonThreadFactory;
 17  
 
 18  
 import edu.emory.mathcs.backport.java.util.concurrent.Callable;
 19  
 import edu.emory.mathcs.backport.java.util.concurrent.ExecutionException;
 20  
 import edu.emory.mathcs.backport.java.util.concurrent.Executor;
 21  
 import edu.emory.mathcs.backport.java.util.concurrent.Executors;
 22  
 import edu.emory.mathcs.backport.java.util.concurrent.FutureTask;
 23  
 import edu.emory.mathcs.backport.java.util.concurrent.TimeUnit;
 24  
 import edu.emory.mathcs.backport.java.util.concurrent.TimeoutException;
 25  
 
 26  
 /**
 27  
  * <code>FutureMessageResult</code> is an UMOMessage result of a remote invocation
 28  
  * on a Mule Server. This object makes the result available to the client code once
 29  
  * the request has been processed. This execution happens asynchronously.
 30  
  */
 31  
 // @ThreadSafe
 32  
 public class FutureMessageResult extends FutureTask
 33  
 {
 34  
     /**
 35  
      * This is a simple default Executor for FutureMessageResults. Instead of
 36  
      * spawning a Thread for each invocation it uses a single daemon Thread with an
 37  
      * unbounded queue, so "truly" concurrent operation of multiple Futures or
 38  
      * otherwise customized execution behaviour requires calling the
 39  
      * {@link #setExecutor(Executor)} method and passing in a custom {@link Executor}.
 40  
      * This is strongly recommended in order to provide better control over
 41  
      * concurrency, resource consumption and possible overruns.
 42  
      * <p>
 43  
      * Reasons for these defaults:
 44  
      * <ul>
 45  
      * <li> a daemon thread does not block the VM on shutdown; lifecycle control
 46  
      * should be done elsewhere (e.g. the provider of the custom ExecutorService),
 47  
      * otherwise this class would become too overloaded
 48  
      * <li> a single thread provides for conservative & predictable yet async
 49  
      * behaviour from a client's point of view
 50  
      * <li> the unbounded queue is not optimal but probably harmless since e.g. a
 51  
      * MuleClient would have to create a LOT of Futures for an OOM. Cancelled/timed
 52  
      * out invocations are GC'ed so the problem is rather unlikely to occur.
 53  
      * </ul>
 54  
      */
 55  0
     private static final Executor DefaultExecutor = Executors.newSingleThreadExecutor(
 56  
         new DaemonThreadFactory("MuleDefaultFutureMessageExecutor"));
 57  
 
 58  
     // @GuardedBy(this)
 59  
     private Executor executor;
 60  
 
 61  
     // @GuardedBy(this)
 62  
     private UMOTransformer transformer;
 63  
 
 64  
     public FutureMessageResult(Callable callable)
 65  
     {
 66  0
         super(callable);
 67  0
         this.executor = DefaultExecutor;
 68  0
     }
 69  
 
 70  
     /**
 71  
      * Set an ExecutorService to run this invocation.
 72  
      * 
 73  
      * @param e the executor to be used.
 74  
      * @throws IllegalArgumentException when the executor is null or shutdown.
 75  
      */
 76  
     public void setExecutor(Executor e)
 77  
     {
 78  0
         if (e == null)
 79  
         {
 80  0
             throw new IllegalArgumentException("Executor must not be null.");
 81  
         }
 82  
 
 83  0
         synchronized (this)
 84  
         {
 85  0
             this.executor = e;
 86  0
         }
 87  0
     }
 88  
 
 89  
     /**
 90  
      * Set a post-invocation transformer.
 91  
      * 
 92  
      * @param t UMOTransformer to be applied to the result of this invocation. May be
 93  
      *            null.
 94  
      */
 95  
     public void setTransformer(UMOTransformer t)
 96  
     {
 97  0
         synchronized (this)
 98  
         {
 99  0
             this.transformer = t;
 100  0
         }
 101  0
     }
 102  
 
 103  
     public UMOMessage getMessage() throws InterruptedException, ExecutionException, TransformerException
 104  
     {
 105  0
         return this.getMessage(this.get());
 106  
     }
 107  
 
 108  
     public UMOMessage getMessage(long timeout)
 109  
         throws InterruptedException, ExecutionException, TimeoutException, TransformerException
 110  
     {
 111  0
         return this.getMessage(this.get(timeout, TimeUnit.MILLISECONDS));
 112  
     }
 113  
 
 114  
     private UMOMessage getMessage(Object obj) throws TransformerException
 115  
     {
 116  0
         if (obj != null)
 117  
         {
 118  0
             if (obj instanceof UMOMessage)
 119  
             {
 120  0
                 return (UMOMessage)obj;
 121  
             }
 122  
 
 123  0
             synchronized (this)
 124  
             {
 125  0
                 if (transformer != null)
 126  
                 {
 127  0
                     obj = transformer.transform(obj);
 128  
                 }
 129  0
             }
 130  
 
 131  0
             return new MuleMessage(obj);
 132  
         }
 133  
         else
 134  
         {
 135  0
             return null;
 136  
         }
 137  
     }
 138  
 
 139  
     /**
 140  
      * Start asynchronous execution of this task
 141  
      */
 142  
     public void execute()
 143  
     {
 144  0
         synchronized (this)
 145  
         {
 146  0
             executor.execute(this);
 147  0
         }
 148  0
     }
 149  
 
 150  
 }