View Javadoc

1   package org.apache.turbine.modules.layouts;
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.ecs.ConcreteElement;
27  import org.apache.turbine.TurbineConstants;
28  import org.apache.turbine.modules.Layout;
29  import org.apache.turbine.modules.Screen;
30  import org.apache.turbine.modules.ScreenLoader;
31  import org.apache.turbine.pipeline.PipelineData;
32  import org.apache.turbine.services.assemblerbroker.TurbineAssemblerBroker;
33  import org.apache.turbine.services.velocity.TurbineVelocity;
34  import org.apache.turbine.util.RunData;
35  import org.apache.turbine.util.template.TemplateNavigation;
36  import org.apache.velocity.context.Context;
37  
38  /**
39   * This Layout module allows Velocity templates to be used as layouts.
40   * Since dynamic content is supposed to be primarily located in
41   * screens and navigations there should be relatively few reasons to
42   * subclass this Layout.
43   *
44   * To get the same functionality as with VelocityECSLayout, you can use two
45   * supplied VelocityMacros, TurbineHtmlHead and TurbineHtmlBodyAttributes
46   * in your templates. These are used to put HtmlPageAttributes into a page
47   * before rendering.
48   *
49   * Use these macros should be used in the Layout template like this:
50   *
51   * ... set things like style sheets, scripts here.
52   * <html>
53   * #TurbineHtmlHead()
54   * <body #TurbineHtmlBodyAttributes() >
55   *  .... your body information
56   * </body>
57   * </html>
58   *
59   * As the layout template is rendered _after_ the screen template, you
60   * can of course, add information to the $page tool in your screen template.
61   * This will be added correctly to the <head>...</head> and
62   * <body> tags.
63   *
64   * @author <a href="mailto:john.mcnally@clearink.com">John D. McNally</a>
65   * @author <a href="mailto:mbryson@mont.mindspring.com">Dave Bryson</a>
66   * @author <a href="mailto:hps@intermeta.de">Henning P. Schmiedehausen</a>
67   * @author <a href="mailto:peter@courcoux.biz">Peter Courcoux</a>
68   * @version $Id: VelocityOnlyLayout.java 1066558 2011-02-02 18:12:40Z ludwig $
69   */
70  public class VelocityOnlyLayout
71      extends Layout
72  {
73      /** Logging */
74      private static Log log = LogFactory.getLog(VelocityOnlyLayout.class);
75  
76      /** The prefix for lookup up layout pages */
77      private String prefix = Layout.PREFIX + "/";
78  
79      private ScreenLoader screenLoader;
80  
81      /**
82       * Default constructor
83       */
84      public VelocityOnlyLayout()
85      {
86          super();
87  
88          this.screenLoader = (ScreenLoader)TurbineAssemblerBroker.getLoader(Screen.NAME);
89      }
90  
91      /**
92       * Build the layout.  Also sets the ContentType and Locale headers
93       * of the HttpServletResponse object.
94       * @deprecated Use PipelineData version
95       * @param data Turbine information.
96       * @exception Exception a generic exception.
97       */
98      @Deprecated
99      @Override
100     public void doBuild(RunData data)
101         throws Exception
102     {
103         // Get the context needed by Velocity.
104         Context context = TurbineVelocity.getContext(data);
105 
106         String screenName = data.getScreen();
107 
108         log.debug("Loading Screen " + screenName);
109 
110         // First, generate the screen and put it in the context so
111         // we can grab it the layout template.
112         ConcreteElement results =
113             screenLoader.eval(data, screenName);
114 
115         String returnValue = (results == null) ? "" : results.toString();
116 
117         // variable for the screen in the layout template
118         context.put(TurbineConstants.SCREEN_PLACEHOLDER, returnValue);
119 
120         // variable to reference the navigation screen in the layout template
121         context.put(TurbineConstants.NAVIGATION_PLACEHOLDER,
122                     new TemplateNavigation(data));
123 
124         // Grab the layout template set in the VelocityPage.
125         // If null, then use the default layout template
126         // (done by the TemplateInfo object)
127         String templateName = data.getTemplateInfo().getLayoutTemplate();
128 
129         // Set the locale and content type
130         data.getResponse().setLocale(data.getLocale());
131         data.getResponse().setContentType(data.getContentType());
132 
133         log.debug("Now trying to render layout " + templateName);
134 
135         // Finally, generate the layout template and send it to the browser
136         TurbineVelocity.handleRequest(context,
137                 prefix + templateName, data.getResponse().getOutputStream());
138     }
139 
140     /**
141      * Build the layout.  Also sets the ContentType and Locale headers
142      * of the HttpServletResponse object.
143      *
144      *
145      * @param data PipelineData
146      * @throws Exception generic exception
147      */
148     @Override
149     public void doBuild(PipelineData pipelineData)
150         throws Exception
151     {
152         RunData data = getRunData(pipelineData);
153         // Get the context needed by Velocity.
154         Context context = TurbineVelocity.getContext(pipelineData);
155 
156         String screenName = data.getScreen();
157 
158         log.debug("Loading Screen " + screenName);
159 
160         // First, generate the screen and put it in the context so
161         // we can grab it the layout template.
162         ConcreteElement results =
163             screenLoader.eval(pipelineData, screenName);
164 
165         String returnValue = (results == null) ? "" : results.toString();
166 
167         // variable for the screen in the layout template
168         context.put(TurbineConstants.SCREEN_PLACEHOLDER, returnValue);
169 
170         // variable to reference the navigation screen in the layout template
171         context.put(TurbineConstants.NAVIGATION_PLACEHOLDER,
172                     new TemplateNavigation(data));
173 
174         // Grab the layout template set in the VelocityPage.
175         // If null, then use the default layout template
176         // (done by the TemplateInfo object)
177         String templateName = data.getTemplateInfo().getLayoutTemplate();
178 
179         // Set the locale and content type
180         data.getResponse().setLocale(data.getLocale());
181         data.getResponse().setContentType(data.getContentType());
182 
183         log.debug("Now trying to render layout " + templateName);
184 
185         // Finally, generate the layout template and send it to the browser
186         TurbineVelocity.handleRequest(context,
187                 prefix + templateName, data.getResponse().getOutputStream());
188     }
189 }