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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 2001-2005 (C) Exoffice Technologies Inc. All Rights Reserved.
42   *
43   * $Id: ConnectorHelper.java,v 1.2 2005/08/30 05:05:55 tanderson Exp $
44   */
45  package org.exolab.jms.config;
46  
47  import java.io.IOException;
48  import java.io.InputStream;
49  import java.io.InputStreamReader;
50  
51  import org.apache.commons.logging.Log;
52  import org.apache.commons.logging.LogFactory;
53  
54  import org.exolab.jms.config.types.SchemeType;
55  
56  
57  /***
58   * ConnectorHelper is a utility class that returns {@link ConnectorResource}
59   * objects for a given scheme.
60   *
61   * @version     $Revision: 1.2 $ $Date: 2005/08/30 05:05:55 $
62   * @author      <a href="mailto:tma@netspace.net.au">Tim Anderson</a>
63   */
64  public class ConnectorHelper {
65  
66      /***
67       * The default connector resource configurations.
68       */
69      private static final ConnectorResource[] _connectors;
70  
71      /***
72       * The logger.
73       */
74      private static final Log _log = LogFactory.getLog(ConnectorHelper.class);
75  
76      /***
77       * The connector configuration path as a resource.
78       */
79      private static final String RESOURCE =
80          "/org/exolab/jms/config/connectors.xml";
81  
82  
83      /***
84       * Returns the connector resource for the supplied scheme, from
85       * the supplied configuration. If the configuration doesn't define
86       * any connector resources, the default connector for the scheme will be
87       * returned.
88       *
89       * @param scheme the connector scheme
90       * @param config the configuration
91       * @return the connector configuration, or null if none exists
92       */
93      public static ConnectorResource getConnectorResource(
94          SchemeType scheme, Configuration config) {
95  
96          if (scheme == null) {
97              throw new IllegalArgumentException("Argument 'scheme' is null");
98          }
99          if (config == null) {
100             throw new IllegalArgumentException("Argument 'config' is null");
101         }
102 
103         ConnectorResource result = null;
104         ConnectorResource[] connectors = _connectors;
105         if (config.getConnectorResources() != null) {
106             // use the specified resources, if any
107             connectors = config.getConnectorResources().getConnectorResource();
108         }
109 
110         String name = scheme.toString();
111         for (int i = 0; i < connectors.length; ++i) {
112             if (connectors[i].getScheme().toString().equals(name)) {
113                 result = connectors[i];
114                 break;
115             }
116         }
117         return result;
118     }
119 
120     static {
121         // load the default connector resources
122 
123         InputStream stream = null;
124         try {
125             ConnectorResources connectors = null;
126             stream = ConnectorHelper.class.getResourceAsStream(RESOURCE);
127             connectors = ConnectorResources.unmarshal(
128                 new InputStreamReader(stream));
129             _connectors = connectors.getConnectorResource();
130         } catch (Exception exception) {
131             _log.error(exception, exception);
132             throw new RuntimeException(exception.getMessage());
133         } finally {
134             if (stream != null) {
135                 try {
136                     stream.close();
137                 } catch (IOException ignore) {
138                 }
139             }
140         }
141     }
142 
143 }