View Javadoc

1   /*
2    * $Id: TilesListener.java 609762 2008-01-07 19:53:08Z apetrelli $
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  package org.apache.tiles.web.startup;
22  
23  import org.apache.commons.logging.Log;
24  import org.apache.commons.logging.LogFactory;
25  import org.apache.tiles.TilesContainer;
26  import org.apache.tiles.TilesException;
27  import org.apache.tiles.access.TilesAccess;
28  import org.apache.tiles.factory.TilesContainerFactory;
29  
30  import javax.servlet.ServletContext;
31  import javax.servlet.ServletContextEvent;
32  import javax.servlet.ServletContextListener;
33  
34  /***
35   * Listener for the initialization of the Tiles container.
36   *
37   * @version $Rev: 609762 $ $Date: 2008-01-07 20:53:08 +0100 (Mon, 07 Jan 2008) $
38   */
39  public class TilesListener
40      implements ServletContextListener {
41  
42      /***
43       * Log instance.
44       */
45      protected static final Log LOG =
46          LogFactory.getLog(TilesListener.class);
47  
48      /***
49       * Initialize the TilesContainer and place it
50       * into service.
51       *
52       * @param event The intercepted event.
53       */
54      public void contextInitialized(ServletContextEvent event) {
55          ServletContext servletContext = event.getServletContext();
56          try {
57              TilesContainer container = createContainer(servletContext);
58              TilesAccess.setContainer(servletContext, container);
59          } catch (TilesException e) {
60              throw new IllegalStateException("Unable to instantiate container.",
61                      e);
62          }
63      }
64  
65      /***
66       * Remove the tiles container from service.
67       *
68       * @param event The intercepted event.
69       */
70      public void contextDestroyed(ServletContextEvent event) {
71          ServletContext servletContext = event.getServletContext();
72          try {
73              TilesAccess.setContainer(servletContext, null);
74          } catch (TilesException e) {
75              LOG.warn("Unable to remove tiles container from service.");
76          }
77      }
78  
79      /***
80       * Creates a Tiles container.
81       *
82       * @param context The servlet context to use.
83       * @return The created container
84       * @throws TilesException If something goes wrong during creation.
85       */
86      protected TilesContainer createContainer(ServletContext context)
87          throws TilesException {
88          TilesContainerFactory factory =
89              TilesContainerFactory.getFactory(context);
90          return factory.createContainer(context);
91      }
92  
93  }