001package org.apache.turbine.modules.pages; 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 024import org.apache.turbine.annotation.TurbineService; 025import org.apache.turbine.pipeline.PipelineData; 026import org.apache.turbine.services.template.TemplateService; 027import org.apache.turbine.util.RunData; 028import org.apache.turbine.util.TurbineException; 029 030/** 031 * When building sites using templates, Screens need only be defined 032 * for templates which require dynamic (database or object) data. 033 * 034 * <p> 035 * 036 * This page can be used on sites where the number of Screens can be 037 * much less than the number of templates. The templates can be 038 * grouped in directories with common layouts. Screen modules are 039 * then expected to be placed in packages corresponding with the 040 * templates' directories and follow a specific naming scheme. 041 * 042 * <p> 043 * 044 * The template parameter is parsed and and a Screen whose package 045 * matches the templates path and shares the same name minus any 046 * extension and beginning with a capital letter is searched for. If 047 * not found, a Screen in a package matching the template's path with 048 * name Default is searched for. If still not found, a Screen with 049 * name Default is looked for in packages corresponding to parent 050 * directories in the template's path until a match is found. 051 * 052 * <p> 053 * 054 * For example if data.getParameters().getString("template") returns 055 * /about_us/directions/driving.wm, the search follows 056 * about_us.directions.Driving, about_us.directions.Default, 057 * about_us.Default, Default, WebMacroSiteScreen (i.e. the default 058 * screen set in TurbineResources). 059 * 060 * <p> 061 * 062 * Only one Layout module is used, since it is expected that any 063 * dynamic content will be placed in navigations and screens. The 064 * layout template to be used is found in a similar way to the Screen. 065 * For example the following paths will be searched in the layouts 066 * subdirectory: /about_us/directions/driving.wm, 067 * /about_us/directions/default.wm, /about_us/default.wm, /default.wm, 068 * where wm is the value of the template.default.extension property. 069 * 070 * <p> 071 * 072 * This approach allows a site with largely static content to be 073 * updated and added to regularly by those with little Java 074 * experience. 075 * 076 * @author <a href="mailto:john.mcnally@clearink.com">John D. McNally</a> 077 * @author <a href="mailto:mbryson@mont.mindspring.com">Dave Bryson</a> 078 * @author <a href="mailto:hps@intermeta.de">Henning P. Schmiedehausen</a> 079 * @author <a href="mailto:peter@courcoux.biz">Peter Courcoux</a> 080 * @version $Id$ 081 */ 082public class TemplatePage 083 extends DefaultPage 084{ 085 /** Injected service instance */ 086 @TurbineService 087 private TemplateService templateService; 088 089 /** 090 * Works with TemplateService to set up default templates and 091 * corresponding class modules. 092 * 093 * @param pipelineData Turbine information. 094 * @throws Exception a generic exception. 095 */ 096 @Override 097 protected void doBuildAfterAction(PipelineData pipelineData) 098 throws Exception 099 { 100 RunData data = pipelineData.getRunData(); 101 // The Template Service at this point must fetch the Screen class 102 // to match a given template. If the Screen class has already been 103 // set by an action, skip this, because the user has the already 104 // specified the Screen class he wants to use. 105 if (!data.hasScreen()) 106 { 107 // This is effectively getting the "template" parameter 108 // from the parameter parser in rundata. This is coming 109 // from the request for a template. 110 String template = data.getTemplateInfo().getScreenTemplate(); 111 112 // Get the layout template and the correct Screen. 113 String layoutTemplate = 114 templateService.getLayoutTemplateName(template); 115 data.getTemplateInfo().setLayoutTemplate(layoutTemplate); 116 117 String screen = templateService.getScreenName(template); 118 119 if (screen == null) 120 { 121 String errMsg = "Couldn't map Template " 122 + template + " to any Screen class!"; 123 log.error(errMsg); 124 throw new TurbineException(errMsg); 125 } 126 data.setScreen(screen); 127 } 128 } 129}