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1   package org.apache.turbine.util.template;
2   
3   
4   /*
5    * Licensed to the Apache Software Foundation (ASF) under one
6    * or more contributor license agreements.  See the NOTICE file
7    * distributed with this work for additional information
8    * regarding copyright ownership.  The ASF licenses this file
9    * to you under the Apache License, Version 2.0 (the
10   * "License"); you may not use this file except in compliance
11   * with the License.  You may obtain a copy of the License at
12   *
13   *   http://www.apache.org/licenses/LICENSE-2.0
14   *
15   * Unless required by applicable law or agreed to in writing,
16   * software distributed under the License is distributed on an
17   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
18   * KIND, either express or implied.  See the License for the
19   * specific language governing permissions and limitations
20   * under the License.
21   */
22  
23  
24  import org.apache.commons.logging.Log;
25  import org.apache.commons.logging.LogFactory;
26  import org.apache.turbine.modules.NavigationLoader;
27  import org.apache.turbine.services.TurbineServices;
28  import org.apache.turbine.services.template.TemplateService;
29  import org.apache.turbine.util.RunData;
30  
31  /**
32   * Returns output of a Navigation module.  An instance of this is
33   * placed in the WebMacro context by the WebMacroSiteLayout.  This
34   * allows template authors to set the navigation template they'd like
35   * to place in their templates.  Here's how it's used in a
36   * template:
37   *
38   * <p><code>
39   * $navigation.setTemplate("admin_navigation.wm")
40   * </code>
41   *
42   * @author <a href="mbryson@mont.mindspring.com">Dave Bryson</a>
43   * @version $Id: TemplateNavigation.java 1723699 2016-01-08 11:29:21Z tv $
44   */
45  public class TemplateNavigation
46  {
47      /** Logging */
48      private static Log log = LogFactory.getLog(TemplateNavigation.class);
49  
50      /* The RunData object. */
51      private RunData data;
52  
53      /* The name of the navigation template. */
54      private String template = null;
55  
56      /**
57       * Constructor
58       *
59       * @param data A Turbine RunData object.
60       */
61      public TemplateNavigation(RunData data)
62      {
63          this.data = data;
64      }
65  
66      /**
67       * Set the template.
68       *
69       * @param template A String with the name of the navigation
70       * template.
71       * @return A TemplateNavigation (self).
72       */
73      public TemplateNavigation setTemplate(String template)
74      {
75          log.debug("setTemplate(" + template + ")");
76          this.template = template;
77          return this;
78      }
79  
80      /**
81       * Builds the output of the navigation template.
82       *
83       * @return A String.
84       */
85      @Override
86      public String toString()
87      {
88          String module = null;
89          String returnValue = null;
90  
91          try
92          {
93              if (template == null)
94              {
95                  returnValue = "Navigation Template is null (Might be unset)";
96                  throw new Exception(returnValue);
97              }
98  
99              data.getTemplateInfo().setNavigationTemplate(template);
100             TemplateService templateService = (TemplateService)TurbineServices.getInstance().getService(TemplateService.SERVICE_NAME);
101             module = templateService.getNavigationName(template);
102 
103             if (module == null)
104             {
105                 returnValue = "Template Service returned null for Navigation Template " + template;
106                 throw new Exception(returnValue);
107             }
108 
109             returnValue = NavigationLoader.getInstance().eval(data, module);
110         }
111         catch (Exception e)
112         {
113             if (returnValue == null)
114             {
115                 returnValue = "Error processing navigation template: "
116                         + template + ", using module: " + module;
117             }
118             log.error(returnValue, e);
119         }
120 
121         return returnValue;
122     }
123 }