001 package org.apache.turbine.modules.layouts;
002
003
004 /*
005 * Licensed to the Apache Software Foundation (ASF) under one
006 * or more contributor license agreements. See the NOTICE file
007 * distributed with this work for additional information
008 * regarding copyright ownership. The ASF licenses this file
009 * to you under the Apache License, Version 2.0 (the
010 * "License"); you may not use this file except in compliance
011 * with the License. You may obtain a copy of the License at
012 *
013 * http://www.apache.org/licenses/LICENSE-2.0
014 *
015 * Unless required by applicable law or agreed to in writing,
016 * software distributed under the License is distributed on an
017 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
018 * KIND, either express or implied. See the License for the
019 * specific language governing permissions and limitations
020 * under the License.
021 */
022
023
024 import java.io.StringReader;
025
026 import org.apache.commons.logging.Log;
027 import org.apache.commons.logging.LogFactory;
028 import org.apache.ecs.ConcreteElement;
029 import org.apache.fulcrum.xslt.XSLTServiceFacade;
030 import org.apache.turbine.TurbineConstants;
031 import org.apache.turbine.modules.Layout;
032 import org.apache.turbine.modules.Screen;
033 import org.apache.turbine.modules.ScreenLoader;
034 import org.apache.turbine.pipeline.PipelineData;
035 import org.apache.turbine.services.assemblerbroker.TurbineAssemblerBroker;
036 import org.apache.turbine.services.velocity.TurbineVelocity;
037 import org.apache.turbine.util.RunData;
038 import org.apache.turbine.util.template.TemplateNavigation;
039 import org.apache.velocity.context.Context;
040
041 /**
042 * This Layout module allows Velocity XML templates to be used as layouts.
043 * <br><br>
044 * Once the (XML) screen and navigation templates have been inserted into
045 * the layout template the result is transformed with a XSL stylesheet.
046 * The stylesheet (with the same name than the screen template) is loaded
047 * and executed by the XSLT service, so it is important that you correctly
048 * set up your XSLT service. If the named stylsheet does not exist the
049 * default.xsl stylesheet is executed. If default.xsl does not exist
050 * the XML is merely echoed.
051 * <br><br>
052 * Since dynamic content is supposed to be primarily located in
053 * screens and navigations there should be relatively few reasons to
054 * subclass this Layout.
055 *
056 * @author <a href="mailto:leon@opticode.co.za">Leon Messerschmidt</a>
057 * @author <a href="mailto:hps@intermeta.de">Henning P. Schmiedehausen</a>
058 * @version $Id: VelocityXslLayout.java 1066558 2011-02-02 18:12:40Z ludwig $
059 */
060 public class VelocityXslLayout extends Layout
061 {
062 /** Logging */
063 private static Log log = LogFactory.getLog(VelocityXslLayout.class);
064
065 /** The prefix for lookup up layout pages */
066 private String prefix = Layout.PREFIX + "/";
067
068 private ScreenLoader screenLoader;
069
070 /**
071 * Default constructor
072 */
073 public VelocityXslLayout()
074 {
075 super();
076
077 this.screenLoader = (ScreenLoader)TurbineAssemblerBroker.getLoader(Screen.NAME);
078 }
079
080 /**
081 * Build the layout. Also sets the ContentType and Locale headers
082 * of the HttpServletResponse object.
083 * @deprecated Use PipelineData version instead.
084 * @param data Turbine information.
085 * @exception Exception a generic exception.
086 */
087 @Deprecated
088 @Override
089 public void doBuild(RunData data)
090 throws Exception
091 {
092 // Get the context needed by Velocity.
093 Context context = TurbineVelocity.getContext(data);
094
095 data.getResponse().setContentType("text/html");
096
097 String screenName = data.getScreen();
098
099 log.debug("Loading Screen " + screenName);
100
101 // First, generate the screen and put it in the context so
102 // we can grab it the layout template.
103 ConcreteElement results =
104 screenLoader.eval(data, screenName);
105
106 String returnValue = (results == null) ? "" : results.toString();
107
108 // variable for the screen in the layout template
109 context.put(TurbineConstants.SCREEN_PLACEHOLDER, returnValue);
110
111 // variable to reference the navigation screen in the layout template
112 context.put(TurbineConstants.NAVIGATION_PLACEHOLDER,
113 new TemplateNavigation(data));
114
115 // Grab the layout template set in the VelocityPage.
116 // If null, then use the default layout template
117 // (done by the TemplateInfo object)
118 String templateName = data.getTemplateInfo().getLayoutTemplate();
119
120 log.debug("Now trying to render layout " + templateName);
121
122 // Now, generate the layout template.
123 String temp = TurbineVelocity.handleRequest(context,
124 prefix + templateName);
125
126 // Finally we do a transformation and send the result
127 // back to the browser
128 XSLTServiceFacade.transform(
129 data.getTemplateInfo().getScreenTemplate(),
130 new StringReader(temp), data.getResponse().getWriter());
131 }
132
133 /**
134 * Build the layout. Also sets the ContentType and Locale headers
135 * of the HttpServletResponse object.
136 *
137 * @param data Turbine information.
138 * @exception Exception a generic exception.
139 */
140 @Override
141 public void doBuild(PipelineData pipelineData)
142 throws Exception
143 {
144 RunData data = getRunData(pipelineData);
145 // Get the context needed by Velocity.
146 Context context = TurbineVelocity.getContext(pipelineData);
147
148 data.getResponse().setContentType("text/html");
149
150 String screenName = data.getScreen();
151
152 log.debug("Loading Screen " + screenName);
153
154 // First, generate the screen and put it in the context so
155 // we can grab it the layout template.
156 ConcreteElement results =
157 screenLoader.eval(pipelineData, screenName);
158
159 String returnValue = (results == null) ? "" : results.toString();
160
161 // variable for the screen in the layout template
162 context.put(TurbineConstants.SCREEN_PLACEHOLDER, returnValue);
163
164 // variable to reference the navigation screen in the layout template
165 context.put(TurbineConstants.NAVIGATION_PLACEHOLDER,
166 new TemplateNavigation(data));
167
168 // Grab the layout template set in the VelocityPage.
169 // If null, then use the default layout template
170 // (done by the TemplateInfo object)
171 String templateName = data.getTemplateInfo().getLayoutTemplate();
172
173 log.debug("Now trying to render layout " + templateName);
174
175 // Now, generate the layout template.
176 String temp = TurbineVelocity.handleRequest(context,
177 prefix + templateName);
178
179 // Finally we do a transformation and send the result
180 // back to the browser
181 XSLTServiceFacade.transform(
182 data.getTemplateInfo().getScreenTemplate(),
183 new StringReader(temp), data.getResponse().getWriter());
184 }
185 }