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1   package org.apache.turbine.modules.navigations;
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.turbine.annotation.TurbineService;
25  import org.apache.turbine.modules.Navigation;
26  import org.apache.turbine.pipeline.PipelineData;
27  import org.apache.turbine.services.template.TemplateService;
28  import org.apache.turbine.services.velocity.VelocityService;
29  import org.apache.turbine.util.RunData;
30  import org.apache.velocity.context.Context;
31  
32  /**
33   * VelocityNavigation.  This screen relies on the VelocityPage
34   * being set as the default page.  The doBuildTemplate() assumes the
35   * user has put the template filename in the RunData parameter and set
36   * it to the value of the template file to execute.  Specialized
37   * Navigations screens should extend this class and override the
38   * doBuildTemplate( data , context) method.
39   *
40   * @author <a href="mailto:mbryson@mont.mindspring.com">Dave Bryson</a>
41   * @author <a href="mailto:hps@intermeta.de">Henning P. Schmiedehausen</a>
42   * @author <a href="mailto:peter@courcoux.biz">Peter Courcoux</a>
43   * @version $Id: VelocityNavigation.java 1709648 2015-10-20 17:08:10Z tv $
44   */
45  public class VelocityNavigation
46          extends TemplateNavigation
47  {
48      /** The prefix for lookup up navigation pages */
49      private final String prefix = Navigation.PREFIX + "/";
50  
51      /** Injected service instance */
52      @TurbineService
53      private VelocityService velocity;
54  
55      /** Injected service instance */
56      @TurbineService
57      private TemplateService templateService;
58  
59      /**
60       * Velocity Navigations extending this class should override this
61       * method to perform any particular business logic and add
62       * information to the context.
63       *
64       * @param pipelineData Turbine information.
65       * @param context Context for web pages.
66       * @exception Exception, a generic exception.
67       */
68      protected void doBuildTemplate(PipelineData pipelineData,
69                                     Context context)
70              throws Exception
71      {
72          // empty
73      }
74  
75      /**
76       * Needs to be implemented to make TemplateNavigation like us.
77       * The actual method that you should override is the one with the
78       * context in the parameter list.
79       *
80       * @param pipelineData Turbine information.
81       * @exception Exception, a generic exception.
82       */
83      @Override
84      protected void doBuildTemplate(PipelineData pipelineData)
85              throws Exception
86      {
87          doBuildTemplate(pipelineData, velocity.getContext(pipelineData));
88      }
89  
90      /**
91       * This builds the Velocity template.
92       *
93       * @param pipelineData Turbine information.
94       * @return the content of the navigation module
95       * @exception Exception, a generic exception.
96       */
97      @Override
98      public String buildTemplate(PipelineData pipelineData)
99              throws Exception
100     {
101         RunData data = getRunData(pipelineData);
102         Context context = velocity.getContext(pipelineData);
103 
104         String navigationTemplate = data.getTemplateInfo().getNavigationTemplate();
105         String templateName
106                 = templateService.getNavigationTemplateName(navigationTemplate);
107 
108         return velocity.handleRequest(context, prefix + templateName);
109     }
110 }