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1   /*
2    * $Id: UrlPreparer.java 1310865 2012-04-07 21:01:22Z nlebas $
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.compat.preparer;
23  
24  import java.io.IOException;
25  
26  import org.apache.tiles.AttributeContext;
27  import org.apache.tiles.preparer.PreparerException;
28  import org.apache.tiles.preparer.ViewPreparer;
29  import org.apache.tiles.request.Request;
30  import org.apache.tiles.request.DispatchRequest;
31  
32  /**
33   * Uses a URL that acts as a preparer. When
34   * {@link org.apache.tiles.preparer.factory.factory.ViewPreparer#execute(Request, AttributeContext)}
35   * is called, the URL is got, but its response is discarded.
36   *
37   * @version $Rev: 1310865 $ $Date: 2012-04-08 07:01:22 +1000 (Sun, 08 Apr 2012) $
38   * @since 2.1.0
39   */
40  public class UrlPreparer implements ViewPreparer {
41  
42      /**
43       * The URL to be used as a preparer.
44       */
45      private String url;
46  
47      /**
48       * Constructor.
49       *
50       * @param url The URL to be used as a preparer.
51       */
52      public UrlPreparer(String url) {
53          this.url = url;
54      }
55  
56      /** {@inheritDoc} */
57      @Override
58      public void execute(Request tilesContext,
59              AttributeContext attributeContext) {
60  
61          if (tilesContext instanceof DispatchRequest) {
62              try {
63                  ((DispatchRequest) tilesContext).include(url);
64              } catch (IOException e) {
65                  throw new PreparerException("The inclusion of the URL " + url
66                          + " threw an I/O exception", e);
67              }
68          } else {
69              throw new PreparerException("This preparer is restricted to web environments");
70          }
71      }
72  }