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1   /*
2    * $Id: StrutsTilesRequestContext.java 478625 2006-11-23 17:31:52Z wsmoak $
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.struts2.tiles;
22  
23  import com.opensymphony.xwork2.ActionInvocation;
24  import com.opensymphony.xwork2.inject.Container;
25  import org.apache.commons.logging.Log;
26  import org.apache.commons.logging.LogFactory;
27  import org.apache.struts2.ServletActionContext;
28  import org.apache.struts2.dispatcher.Dispatcher;
29  import org.apache.struts2.views.freemarker.FreemarkerResult;
30  import org.apache.tiles.context.TilesRequestContext;
31  import org.apache.tiles.context.TilesRequestContextWrapper;
32  
33  import javax.servlet.ServletException;
34  import javax.servlet.http.HttpServletRequest;
35  import javax.servlet.http.HttpServletResponse;
36  import java.io.IOException;
37  
38  /***
39   * Default implementation of TilesUtil.
40   * This class contains default implementation of utilities. This implementation
41   * is intended to be used without Struts.
42   * <p/>
43   * TilesUtilImpl implementation used to intercept .ftl requests and
44   * ensure that they are setup properly to take advantage of the
45   * {@link FreemarkerResult}.
46   *
47   * @version $Id: StrutsTilesRequestContext.java 478625 2006-11-23 17:31:52Z wsmoak $
48   */
49  public class StrutsTilesRequestContext extends TilesRequestContextWrapper {
50  
51      private static final Log LOG =
52              LogFactory.getLog(StrutsTilesRequestContext.class);
53  
54  
55      /***
56       * The mask used to detect requests which should be intercepted.
57       */
58      private String mask;
59  
60      /***
61       * Default constructor.
62       * Sets the mask to '.ftl'
63       *
64       * @param context
65       */
66      public StrutsTilesRequestContext(TilesRequestContext context) {
67          this(context, ".ftl");
68      }
69  
70      /***
71       * Optional constructor used to specify a specific mask.
72       *
73       * @param mask
74       * @param context
75       */
76      public StrutsTilesRequestContext(TilesRequestContext context,
77                                       String mask) {
78          super(context);
79          this.mask = mask;
80      }
81  
82      public void dispatch(String include) throws IOException {
83          include(include);
84      }
85  
86      /***
87       * Enhancement of the default include which allows for freemarker
88       * templates to be intercepted so that the FreemarkerResult can
89       * be used in order to setup the appropriate model.
90       *
91       * @throws IOException
92       */
93      public void include(String include) throws IOException {
94          if (include.endsWith(mask)) {
95              if (LOG.isDebugEnabled()) {
96                  LOG.debug("Intercepting tiles include '" + include + "'. Processing as freemarker result.");
97              }
98              HttpServletRequest request = (HttpServletRequest) getRequest();
99              HttpServletResponse response = (HttpServletResponse) getResponse();
100 
101             ActionInvocation invocation =
102                     ServletActionContext.getActionContext(request).getActionInvocation();
103 
104             try {
105                 FreemarkerResult result = new FreemarkerResult();
106                 result.setWriter(response.getWriter());
107 
108                 Container container = Dispatcher.getInstance()
109                         .getConfigurationManager()
110                         .getConfiguration().getContainer();
111 
112                 container.inject(result);
113 
114                 result.doExecute(include, invocation);
115             } catch (Exception e) {
116                 LOG.error("Error invoking Freemarker template", e);
117                 throw new IOException("Error invoking Freemarker template." + e.getMessage());
118             }
119         } else {
120             super.include(include);
121         }
122     }
123 
124 }