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1   /*** 
2    * 
3    * Copyright 2004 Protique Ltd
4    * 
5    * Licensed under the Apache License, Version 2.0 (the "License"); 
6    * you may not use this file except in compliance with the License. 
7    * You may obtain a copy of the License at 
8    * 
9    * http://www.apache.org/licenses/LICENSE-2.0
10   * 
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS, 
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 
14   * See the License for the specific language governing permissions and 
15   * limitations under the License. 
16   * 
17   **/
18  package org.codehaus.activemq;
19  
20  import org.codehaus.activemq.broker.BrokerContainerFactory;
21  import org.codehaus.activemq.util.JMSExceptionHelper;
22  
23  import javax.jms.JMSException;
24  import java.lang.reflect.Method;
25  
26  /***
27   * Helper methods to avoid a runtime dependency on Spring unless its
28   * used to configure the ActiveMQ broker via the XML configuration
29   *
30   * @version $Revision: 1.1 $
31   */
32  public class XmlConfigHelper {
33      private static final Class[] ARGUMENT_TYPES = {String.class};
34      public static final String SPRING_CLASS_NAME = "org.codehaus.activemq.spring.SpringBrokerContainerFactory";
35  
36      /***
37       * Creates an instance of the broker factory which uses the Spring XML configuration file
38       * mechanism.
39       */
40      public static BrokerContainerFactory createBrokerContainerFactory(String xmlConfig) throws JMSException {
41          try {
42              Class factoryClass = getSpringFactoryClass();
43              Method method = factoryClass.getMethod("newFactory", ARGUMENT_TYPES);
44              if (method == null) {
45                  throw new JMSException("Could not find newFactory() method - classpath strangeness occurred");
46              }
47              return (BrokerContainerFactory) method.invoke(null, new Object[]{xmlConfig});
48          }
49          catch (JMSException e) {
50              throw e;
51          }
52          catch (ClassNotFoundException e) {
53              throw JMSExceptionHelper.newJMSException("Could not configure broker using XML configuration file as Spring factory class could not be loaded. Maybe you need the Spring.jar on your classpath? Reason: " + e, e);
54          }
55          catch (Exception e) {
56              throw JMSExceptionHelper.newJMSException("Could not configure broker using XML configuration file as attempt to use Spring factory failed. Reason: " + e, e);
57          }
58      }
59  
60      private static Class getSpringFactoryClass() throws ClassNotFoundException {
61          Class answer = null;
62          try {
63              answer = Thread.currentThread().getContextClassLoader().loadClass(SPRING_CLASS_NAME);
64          }
65          catch (ClassNotFoundException e) {
66              answer = XmlConfigHelper.class.getClassLoader().loadClass(SPRING_CLASS_NAME);
67          }
68          return answer;
69      }
70  }