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1   package org.apache.velocity.runtime.resource.loader;
2   
3   /*
4    * Licensed to the Apache Software Foundation (ASF) under one
5    * or more contributor license agreements.  See the NOTICE file
6    * distributed with this work for additional information
7    * regarding copyright ownership.  The ASF licenses this file
8    * to you under the Apache License, Version 2.0 (the
9    * "License"); you may not use this file except in compliance
10   * with the License.  You may obtain a copy of the License at
11   *
12   *   http://www.apache.org/licenses/LICENSE-2.0
13   *
14   * Unless required by applicable law or agreed to in writing,
15   * software distributed under the License is distributed on an
16   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
17   * KIND, either express or implied.  See the License for the
18   * specific language governing permissions and limitations
19   * under the License.    
20   */
21  
22  import org.apache.velocity.exception.VelocityException;
23  import org.apache.velocity.runtime.RuntimeServices;
24  import org.apache.velocity.util.ClassUtils;
25  import org.apache.velocity.util.StringUtils;
26  
27  /**
28   * Factory to grab a template loader.
29   *
30   * @author <a href="mailto:jvanzyl@apache.org">Jason van Zyl</a>
31   * @version $Id: ResourceLoaderFactory.java 687177 2008-08-19 22:00:32Z nbubna $
32   */
33  public class ResourceLoaderFactory
34  {
35      /**
36       * Gets the loader specified in the configuration file.
37       * @param rs
38       * @param loaderClassName
39       * @return TemplateLoader
40       * @throws Exception
41       */
42      public static ResourceLoader getLoader(RuntimeServices rs, String loaderClassName)
43       throws Exception
44      {
45          ResourceLoader loader = null;
46  
47          try
48          {
49              loader = (ResourceLoader) ClassUtils.getNewInstance( loaderClassName );
50  
51              rs.getLog().debug("ResourceLoader instantiated: "
52                                + loader.getClass().getName());
53  
54              return loader;
55          }
56          // The ugly three strike again: ClassNotFoundException,IllegalAccessException,InstantiationException
57          catch(Exception e)
58          {
59              String msg = "Problem instantiating the template loader: "+loaderClassName+".\n" +
60                           "Look at your properties file and make sure the\n" +
61                           "name of the template loader is correct.";
62              rs.getLog().error(msg, e);
63              throw new VelocityException(msg, e);
64          }
65      }
66  }