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Java > Open Source Codes > org > apache > jetspeed > modules > pages > JetspeedTemplatePage


1 /*
2  * Copyright 2000-2004 The Apache Software Foundation.
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  * http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16
17 package org.apache.jetspeed.modules.pages;
18
19 // Turbine Modules
20 import org.apache.turbine.modules.pages.DefaultPage;
21
22 // Turbine Utility Classes
23 import org.apache.turbine.util.RunData;
24 import org.apache.turbine.services.template.TurbineTemplate;
25
26 // Jetspeed Classes
27 import org.apache.jetspeed.util.MimeType;
28 import org.apache.jetspeed.om.registry.MediaTypeEntry;
29 import org.apache.jetspeed.services.logging.JetspeedLogFactoryService;
30 import org.apache.jetspeed.services.logging.JetspeedLogger;
31 import org.apache.jetspeed.services.Registry;
32 import org.apache.jetspeed.capability.CapabilityMap;
33 import org.apache.jetspeed.services.TemplateLocator;
34 import org.apache.jetspeed.services.rundata.JetspeedRunData;
35 import org.apache.jetspeed.services.resources.JetspeedResources;
36
37 /**
38  * When building sites using templates, Screens need only be defined
39  * for templates which require dynamic (database or object) data.
40  *
41  * <p>
42  *
43  * This page can be used on sites where the number of Screens can be
44  * much less than the number of templates. The templates can be
45  * grouped in directories with common layouts. Screen modules are
46  * then expected to be placed in packages corresponding with the
47  * templates' directories and follow a specific naming scheme.
48  *
49  * <p>
50  *
51  * The template parameter is parsed and and a Screen whose package
52  * matches the templates path and shares the same name minus any
53  * extension and beginning with a capital letter is searched for. If
54  * not found, a Screen in a package matching the template's path with
55  * name Default is searched for. If still not found, a Screen with
56  * name Default is looked for in packages corresponding to parent
57  * directories in the template's path until a match is found.
58  *
59  * <p>
60  *
61  * For example if data.getParameters().getString("template") returns
62  * /about_us/directions/driving.wm, the search follows
63  * about_us.directions.Driving, about_us.directions.Default,
64  * about_us.Default, Default, WebMacroSiteScreen (i.e. the default
65  * screen set in TurbineResources).
66  *
67  * <p>
68  *
69  * Only one Layout module is used, since it is expected that any
70  * dynamic content will be placed in navigations and screens. The
71  * layout template to be used is found in a similar way to the Screen.
72  * For example the following paths will be searched in the layouts
73  * subdirectory: /about_us/directions/driving.wm,
74  * /about_us/directions/default.wm, /about_us/default.wm, /default.wm,
75  * where wm is the value of the template.default.extension property.
76  *
77  * <p>
78  *
79  * This approach allows a site with largely static content to be
80  * updated and added to regularly by those with little Java
81  * experience.
82  *
83  * @author <a HREF="mailto:john.mcnally@clearink.com">John D. McNally</a>
84  * @author <a HREF="mailto:mbryson@mont.mindspring.com">Dave Bryson</a>
85  * @author <a HREF="mailto:paulsp@apache.org">Paul Spencer</a>
86  * @version $Id: JetspeedTemplatePage.java,v 1.24 2004/02/23 02:59:52 jford Exp $
87  */
88 public class JetspeedTemplatePage extends DefaultPage
89 {
90     private static int httpLifetime = JetspeedResources.getInt("http.lifetime", -1);
91
92     /**
93      * Static initialization of the logger for this class
94      */
95     private static final JetspeedLogger logger = JetspeedLogFactoryService.getLogger(JetspeedTemplatePage.class.getName());
96     
97     /**
98      * Works with TemplateService to set up default templates and
99      * corresponding class modules.
100      *
101      * @param data Turbine information.
102      * @exception Exception, a generic exception.
103      */
104     protected void doBuildBeforeAction(RunData data) throws Exception JavaDoc
105     {
106         switch (httpLifetime)
107         {
108             case -1:
109                 break;
110             case 0:
111                 data.getResponse().setHeader("Cache-Control", "no-cache");
112                 data.getResponse().setHeader("Pragma", "no-cache");
113                 data.getResponse().setDateHeader("Expires", 0);
114                 data.getResponse().setDateHeader("Last-Modified", System.currentTimeMillis());
115                 break;
116             default:
117                 data.getResponse().setHeader("Cache-Control", "max-age=" + httpLifetime);
118                 data.getResponse().setDateHeader("Expires", System.currentTimeMillis() + (httpLifetime * 1000));
119                 data.getResponse().setDateHeader("Last-Modified", System.currentTimeMillis());
120                 break;
121         }
122
123         //Set the ContentType of the page
124 CapabilityMap cm = ((JetspeedRunData)data).getCapability();
125         MimeType mime = cm.getPreferredType();
126         String JavaDoc characterSet = JetspeedResources.getString(JetspeedResources.CONTENT_ENCODING_KEY,"utf-8");
127         data.setContentType( mime.getContentType());
128         if ( mime != null )
129         {
130             MediaTypeEntry media = (MediaTypeEntry)Registry.getEntry(Registry.MEDIA_TYPE, mime.getCode());
131             if ( media != null && media.getCharacterSet() != null)
132             {
133                 characterSet = media.getCharacterSet();
134             }
135         }
136         data.setCharSet( characterSet );
137
138         if (logger.isDebugEnabled())
139         {
140             logger.debug( "JetspeedTemplatePage: Setting type to: " + cm.getPreferredType().getContentType()
141                         + "; charset=" + JetspeedResources.getString(JetspeedResources.CONTENT_ENCODING_KEY,"utf-8")
142                      );
143         }
144
145     }
146
147     /**
148      * Works with TemplateService to set up default templates and
149      * corresponding class modules.
150      *
151      * @param data Turbine information.
152      * @exception Exception, a generic exception.
153      */
154     protected void doBuildAfterAction(RunData data) throws Exception JavaDoc
155     {
156         // Either template or screen should be guaranteed by the SessionValidator
157 // It is occasionally better to specify the screen instead of template
158 // in cases where multiple Screens map to one template. The template
159 // is hardcoded into the Screen in this instance. In this case this
160 // action is skipped.
161
162         if (!data.hasScreen())
163         {
164
165             // if only a screen but no template is specified, then we need to display
166 // a legacy ecs screen --> screenTemplate = ECS
167 if ( data.getTemplateInfo().getScreenTemplate() == null )
168             {
169                 String JavaDoc screen = TurbineTemplate.getDefaultScreen();
170                 data.setScreenTemplate(screen);
171             }
172
173             String JavaDoc ext = TurbineTemplate.getDefaultExtension();
174
175             String JavaDoc template = data.getTemplateInfo().getScreenTemplate();
176
177             //save the initial requested template before mangling it
178 ((JetspeedRunData)data).setRequestedTemplate(template);
179
180             if (template.lastIndexOf('.')<0)
181             {
182                 template=template+"."+ext;
183             }
184             if ( logger.isDebugEnabled() )
185             {
186                 logger.debug("JetspeedTemplatePage: requested template = " + template);
187             }
188
189             // get real path now - this is a fix to get us thru 1.3a2
190 // when the TurbineTemplateService can locate resources by NLS and mediatype,
191 // then it can be removed
192
193             String JavaDoc locatedScreen = TemplateLocator.locateScreenTemplate(data, template);
194             data.setScreenTemplate( locatedScreen );
195             if ( logger.isDebugEnabled() )
196             {
197                 logger.debug("JetspeedTemplatePage: calculated template = " + locatedScreen);
198             }
199
200             String JavaDoc layout = TemplateLocator.locateLayoutTemplate(data, template);
201             data.setLayoutTemplate(layout);
202             if ( logger.isDebugEnabled() )
203             {
204                 logger.debug("JetspeedTemplatePage: layoutTemplate is finally " + layout);
205             }
206
207             String JavaDoc screen = TurbineTemplate.getScreenName(template);
208             if (screen == null)
209             {
210                 throw new Exception JavaDoc("Screen could not be determined. \n" +
211                     "No matches were found by TemplateService and the \n" +
212                     "services.TurbineTemplateService.default.screen \n" +
213                     "property was not set.");
214             }
215             data.setScreen(screen);
216         }
217     }
218
219 }
220
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