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1   /*
2    * $Id: AbstractTilesInitializer.java 797540 2009-07-24 15:42:00Z 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  
22  package org.apache.tiles.startup;
23  
24  import org.apache.tiles.TilesApplicationContext;
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.AbstractTilesContainerFactory;
29  import org.slf4j.Logger;
30  import org.slf4j.LoggerFactory;
31  
32  /***
33   * Default Tiles initialization delegate implementation under a servlet
34   * environment. It uses init parameters to create the
35   * {@link TilesApplicationContext} and the {@link TilesContainer}.
36   *
37   * @version $Rev: 797540 $ $Date: 2009-07-24 17:42:00 +0200 (ven, 24 lug 2009) $
38   * @since 2.2.0
39   */
40  public abstract class AbstractTilesInitializer implements TilesInitializer {
41  
42      /***
43       * The logging object.
44       */
45      private Logger log = LoggerFactory.getLogger(getClass());
46  
47      /***
48       * Init parameter to define the key under which the container will be
49       * stored.
50       *
51       * @since 2.1.2
52       */
53      public static final String CONTAINER_KEY_INIT_PARAMETER =
54          "org.apache.tiles.startup.AbstractTilesInitializer.CONTAINER_KEY";
55  
56      /***
57       * The initialized application context.
58       */
59      private TilesApplicationContext applicationContext;
60  
61      /***
62       * The initialized container.
63       */
64      private TilesContainer container;
65  
66      /*** {@inheritDoc} */
67      public void initialize(TilesApplicationContext applicationContext) {
68          this.applicationContext = createTilesApplicationContext(applicationContext);
69          String key = getContainerKey(this.applicationContext);
70          container = createContainer(this.applicationContext);
71          TilesAccess.setContainer(this.applicationContext, container, key);
72      }
73  
74      /*** {@inheritDoc} */
75      public void destroy() {
76          try {
77              TilesAccess.setContainer(applicationContext, null,
78                      getContainerKey(applicationContext));
79          } catch (TilesException e) {
80              log.warn("Unable to remove tiles container from service.", e);
81          }
82      }
83  
84      /***
85       * Creates the Tiles application context, to be used across all the
86       * Tiles-based application. If you override this class, please override this
87       * method or
88       * {@link #createAndInitializeTilesApplicationContextFactory(TilesApplicationContext)}
89       * .<br>
90       * This implementation returns the preliminary context passed as a parameter
91       *
92       * @param preliminaryContext The preliminary application context to use.
93       * @return The Tiles application context.
94       * @since 2.2.0
95       */
96      protected TilesApplicationContext createTilesApplicationContext(
97              TilesApplicationContext preliminaryContext) {
98          return preliminaryContext;
99      }
100 
101     /***
102      * Returns the container key under which the container will be stored.
103      * This implementation returns <code>null</code> so that the container will
104      * be the default one.
105      *
106      * @param applicationContext The Tiles application context to use.
107      * @return The container key.
108      * @since 2.2.0
109      */
110     protected String getContainerKey(TilesApplicationContext applicationContext) {
111         return null;
112     }
113 
114     /***
115      * Creates a Tiles container. If you override this class, please override
116      * this method or {@link #createContainerFactory(TilesApplicationContext)}.
117      *
118      * @param context The servlet context to use.
119      * @return The created container.
120      * @since 2.2.0
121      */
122     protected TilesContainer createContainer(TilesApplicationContext context) {
123         AbstractTilesContainerFactory factory = createContainerFactory(context);
124         return factory.createContainer(context);
125     }
126 
127     /***
128      * Creates a Tiles container factory. If you override this class, please
129      * override this method or {@link #createContainer(TilesApplicationContext)}.
130      *
131      * @param context The servlet context to use.
132      * @return The created container factory.
133      * @since 2.2.0
134      */
135     protected abstract AbstractTilesContainerFactory createContainerFactory(
136             TilesApplicationContext context);
137 }