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1   /*
2    * Copyright (c) MuleSoft, Inc.  All rights reserved.  http://www.mulesoft.com
3    * The software in this package is published under the terms of the CPAL v1.0
4    * license, a copy of which has been included with this distribution in the
5    * LICENSE.txt file.
6    */
7   package org.mule.config.pool;
8   
9   import org.mule.api.MuleContext;
10  import org.mule.api.config.ThreadingProfile;
11  import org.mule.util.StringUtils;
12  import org.mule.util.concurrent.NamedThreadFactory;
13  import org.mule.util.concurrent.WaitPolicy;
14  
15  import edu.emory.mathcs.backport.java.util.concurrent.BlockingQueue;
16  import edu.emory.mathcs.backport.java.util.concurrent.LinkedBlockingDeque;
17  import edu.emory.mathcs.backport.java.util.concurrent.SynchronousQueue;
18  import edu.emory.mathcs.backport.java.util.concurrent.ThreadPoolExecutor;
19  import edu.emory.mathcs.backport.java.util.concurrent.TimeUnit;
20  import org.apache.commons.logging.Log;
21  import org.apache.commons.logging.LogFactory;
22  
23  /**
24  *
25  */
26  public class DefaultThreadPoolFactory extends ThreadPoolFactory
27  {
28      // deliberately shadow the superclass' static logger as to avoid log congestion on it
29      protected final Log logger = LogFactory.getLog(getClass());
30  
31      public ThreadPoolExecutor createPool(String name, ThreadingProfile tp)
32      {
33          BlockingQueue buffer;
34  
35          if (tp.getMaxBufferSize() > 0 && tp.getMaxThreadsActive() > 1)
36          {
37              buffer = new LinkedBlockingDeque(tp.getMaxBufferSize());
38          }
39          else
40          {
41              buffer = new SynchronousQueue();
42          }
43  
44          ThreadPoolExecutor pool = internalCreatePool(name, tp, buffer);
45          configureThreadFactory(name, tp, pool);
46  
47  
48          if (tp.getRejectedExecutionHandler() != null)
49          {
50              pool.setRejectedExecutionHandler(tp.getRejectedExecutionHandler());
51          }
52          else
53          {
54              switch (tp.getPoolExhaustedAction())
55              {
56                  case ThreadingProfile.WHEN_EXHAUSTED_DISCARD_OLDEST :
57                      pool.setRejectedExecutionHandler(new ThreadPoolExecutor.DiscardOldestPolicy());
58                      break;
59                  case ThreadingProfile.WHEN_EXHAUSTED_RUN :
60                      pool.setRejectedExecutionHandler(new ThreadPoolExecutor.CallerRunsPolicy());
61                      break;
62                  case ThreadingProfile.WHEN_EXHAUSTED_ABORT :
63                      pool.setRejectedExecutionHandler(new ThreadPoolExecutor.AbortPolicy());
64                      break;
65                  case ThreadingProfile.WHEN_EXHAUSTED_DISCARD :
66                      pool.setRejectedExecutionHandler(new ThreadPoolExecutor.DiscardPolicy());
67                      break;
68                  default :
69                      // WHEN_EXHAUSTED_WAIT
70                      pool.setRejectedExecutionHandler(new WaitPolicy(tp.getThreadWaitTimeout(), TimeUnit.MILLISECONDS));
71                      break;
72              }
73          }
74  
75          return pool;
76  
77      }
78  
79      protected void configureThreadFactory(String name, ThreadingProfile tp, ThreadPoolExecutor pool)
80      {
81          // use a custom ThreadFactory if one has been configured
82          if (tp.getThreadFactory() != null)
83          {
84              pool.setThreadFactory(tp.getThreadFactory());
85          }
86          else
87          {
88              // ..else create a "NamedThreadFactory" if a proper name was passed in
89              if (StringUtils.isNotBlank(name))
90              {
91                  // Use MuleContext classloader so that other temporary classloaders
92                  // aren't used when things are started lazily or from elsewhere.
93                  pool.setThreadFactory(new NamedThreadFactory(name, MuleContext.class.getClassLoader()));
94              }
95              else
96              {
97                  // let ThreadPoolExecutor create a default ThreadFactory;
98                  // see Executors.defaultThreadFactory()
99              }
100         }
101     }
102 
103     protected ThreadPoolExecutor internalCreatePool(String name, ThreadingProfile tp, BlockingQueue buffer)
104     {
105         return new ThreadPoolExecutor(Math.min(tp.getMaxThreadsIdle(), tp.getMaxThreadsActive()),
106                                       tp.getMaxThreadsActive(), tp.getThreadTTL(),
107                                       TimeUnit.MILLISECONDS, buffer);
108 
109     }
110 }