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1   /***
2    * Redistribution and use of this software and associated documentation
3    * ("Software"), with or without modification, are permitted provided
4    * that the following conditions are met:
5    *
6    * 1. Redistributions of source code must retain copyright
7    *    statements and notices.  Redistributions must also contain a
8    *    copy of this document.
9    *
10   * 2. Redistributions in binary form must reproduce the
11   *    above copyright notice, this list of conditions and the
12   *    following disclaimer in the documentation and/or other
13   *    materials provided with the distribution.
14   *
15   * 3. The name "Exolab" must not be used to endorse or promote
16   *    products derived from this Software without prior written
17   *    permission of Exoffice Technologies.  For written permission,
18   *    please contact info@exolab.org.
19   *
20   * 4. Products derived from this Software may not be called "Exolab"
21   *    nor may "Exolab" appear in their names without prior written
22   *    permission of Exoffice Technologies. Exolab is a registered
23   *    trademark of Exoffice Technologies.
24   *
25   * 5. Due credit should be given to the Exolab Project
26   *    (http://www.exolab.org/).
27   *
28   * THIS SOFTWARE IS PROVIDED BY EXOFFICE TECHNOLOGIES AND CONTRIBUTORS
29   * ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT
30   * NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
31   * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
32   * EXOFFICE TECHNOLOGIES OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
33   * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
34   * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
35   * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
36   * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
37   * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
38   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
39   * OF THE POSSIBILITY OF SUCH DAMAGE.
40   *
41   * Copyright 2005 (C) Exoffice Technologies Inc. All Rights Reserved.
42   *
43   * $Id: ContextInvocationHandler.java,v 1.4 2005/12/01 13:44:38 tanderson Exp $
44   */
45  package org.exolab.jms.net.connector;
46  
47  import org.exolab.jms.net.proxy.Proxy;
48  
49  
50  /***
51   * <code>InvocationHandler</code> implementation that sets the current {@link
52   * ConnectionContext}. before delegating invocations.<br/>
53   * This ensures {@link Proxy} instances are associated with the appropriate
54   * {@link Connection} and {@link ConnectionFactory} on deserialization.
55   *
56   * @author <a href="mailto:tma@netspace.net.au">Tim Anderson</a>
57   * @version $Revision: 1.4 $ $Date: 2005/12/01 13:44:38 $
58   * @see ConnectionContext
59   */
60  public class ContextInvocationHandler implements InvocationHandler {
61  
62      /***
63       * The invocation handler to delegate to.
64       */
65      private final InvocationHandler _handler;
66  
67      /***
68       * The connection performing the invocation.
69       */
70      private ManagedConnection _connection;
71  
72      /***
73       * The connection factory for resolving connections via their URI.
74       */
75      private final ConnectionFactory _resolver;
76  
77  
78      /***
79       * Construct a new <code>ContextInvocationHandler</code>.
80       *
81       * @param handler  the handler to delegate to
82       * @param resolver the connection factory for resolving connections via
83       *                 their URI
84       * @param connection the connection performing the invocation
85       */
86      public ContextInvocationHandler(InvocationHandler handler,
87                                      ConnectionFactory resolver,
88                                      ManagedConnection connection) {
89          _handler = handler;
90          _resolver = resolver;
91          _connection = connection;
92      }
93  
94      /***
95       * Perform an invocation.
96       *
97       * @param invocation the invocation
98       */
99      public void invoke(Invocation invocation) {
100         _handler.invoke(new ContextInvocation(invocation));
101     }
102 
103     private class ContextInvocation implements Invocation {
104 
105         /***
106          * The invocation to delegate to.
107          */
108         private final Invocation _invocation;
109 
110         /***
111          * Construct a new <code>ContextInvocation</code>.
112          *
113          * @param invocation the invocation
114          */
115         public ContextInvocation(Invocation invocation) {
116             _invocation = invocation;
117         }
118 
119         /***
120          * Returns the request.
121          *
122          * @return the request
123          * @throws Throwable for any error
124          */
125         public Request getRequest() throws Throwable {
126             ConnectionContext.push(_connection.getPrincipal(), _resolver);
127             return _invocation.getRequest();
128         }
129 
130         /***
131          * Returns the caller performing the invocation.
132          *
133          * @return the caller
134          */
135         public Caller getCaller() {
136             return _invocation.getCaller();
137         }
138 
139         /***
140          * Sets the result of the invocation.
141          *
142          * @param response the result
143          */
144         public void setResponse(Response response) {
145             try {
146                 _invocation.setResponse(response);
147             } finally {
148                 ConnectionContext.pop();
149             }
150         }
151     }
152 }