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1   /*
2    * $Id: MuleSessionHandler.java 11158 2008-03-04 15:41:08Z 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;
12  
13  import org.mule.api.MuleException;
14  import org.mule.api.MuleMessage;
15  import org.mule.api.MuleSession;
16  import org.mule.api.config.MuleProperties;
17  import org.mule.api.transformer.Transformer;
18  import org.mule.api.transport.SessionHandler;
19  import org.mule.config.i18n.CoreMessages;
20  import org.mule.transformer.codec.Base64Decoder;
21  import org.mule.transformer.codec.Base64Encoder;
22  
23  import java.io.UnsupportedEncodingException;
24  import java.util.Iterator;
25  import java.util.StringTokenizer;
26  
27  import org.apache.commons.logging.Log;
28  import org.apache.commons.logging.LogFactory;
29  
30  /**
31   * A default session handler used to store and retrieve session information on an
32   * event. The DefaultMuleSession information is stored as a header on the message (does not
33   * support Tcp, Udp, etc. unless the MuleMessage object is serialised across the
34   * wire). The session is stored in the "MULE_SESSION" property as String key/value
35   * pairs that are Base64 encoded, for example:
36   * ID=dfokokdf-3ek3oke-dkfokd;MySessionProp1=Value1;MySessionProp2=Value2
37   */
38  public class MuleSessionHandler implements SessionHandler
39  {
40  
41      /**
42       * logger used by this class
43       */
44      protected transient Log logger = LogFactory.getLog(getClass());
45  
46      private static Transformer encoder = new Base64Encoder();
47      private static Transformer decoder = new Base64Decoder();
48  
49      public void retrieveSessionInfoFromMessage(MuleMessage message, MuleSession session) throws MuleException
50      {
51          String sessionId = (String) message.removeProperty(MuleProperties.MULE_SESSION_ID_PROPERTY);
52          Object sessionHeader = message.removeProperty(MuleProperties.MULE_SESSION_PROPERTY);
53  
54          if (sessionId != null)
55          {
56              throw new IllegalStateException(
57                  "This session handler does not know how to look up session information for session id: "
58                                  + sessionId);
59          }
60          if (sessionHeader != null)
61          {
62              String sessionString = null;
63              try
64              {
65                  sessionString = new String((byte[]) decoder.transform(sessionHeader), message.getEncoding());
66              }
67              catch (UnsupportedEncodingException e)
68              {
69                  sessionString = new String((byte[]) decoder.transform(sessionHeader));
70              }
71              if (logger.isDebugEnabled())
72              {
73                  logger.debug("Parsing session header: " + sessionString);
74              }
75              String pair;
76              String name;
77              String value;
78              for (StringTokenizer stringTokenizer = new StringTokenizer(sessionString, ";"); stringTokenizer.hasMoreTokens();)
79              {
80                  pair = stringTokenizer.nextToken();
81                  int i = pair.indexOf("=");
82                  if (i == -1)
83                  {
84                      throw new IllegalArgumentException(
85                          CoreMessages.sessionValueIsMalformed(pair).toString());
86                  }
87                  name = pair.substring(0, i).trim();
88                  value = pair.substring(i + 1).trim();
89                  session.setProperty(name, value);
90                  if (logger.isDebugEnabled())
91                  {
92                      logger.debug("Added MuleSession variable: " + pair);
93                  }
94              }
95  
96          }
97      }
98  
99      public void storeSessionInfoToMessage(MuleSession session, MuleMessage message) throws MuleException
100     {
101         StringBuffer buf = new StringBuffer();
102         buf.append(getSessionIDKey()).append("=").append(session.getId());
103         for (Iterator iterator = session.getPropertyNames(); iterator.hasNext();)
104         {
105             Object o = iterator.next();
106             buf.append(";");
107             buf.append(o).append("=").append(session.getProperty(o));
108             if (logger.isDebugEnabled())
109             {
110                 logger.debug("Adding property to session header: " + o + "=" + session.getProperty(o));
111             }
112         }
113         String sessionString = buf.toString();
114         if (logger.isDebugEnabled())
115         {
116             logger.debug("Adding session header to message: " + sessionString);
117         }
118         sessionString = (String) encoder.transform(sessionString);
119         message.setProperty(MuleProperties.MULE_SESSION_PROPERTY, sessionString);
120     }
121 
122     public String getSessionIDKey()
123     {
124         return "ID";
125     }
126 }