001 package org.apache.turbine.services.template.mapper; 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.util.ArrayList; 025 import java.util.Arrays; 026 import java.util.List; 027 028 import org.apache.commons.lang.StringUtils; 029 import org.apache.commons.logging.Log; 030 import org.apache.commons.logging.LogFactory; 031 import org.apache.turbine.services.template.TemplateEngineService; 032 import org.apache.turbine.services.template.TemplateService; 033 import org.apache.turbine.services.template.TurbineTemplate; 034 035 /** 036 * This mapper is responsible for the lookup of templates for the Layout 037 * It tries to look in various packages for a match: 038 * 039 * 1. about,directions,Driving.vm <- exact match 040 * 2. about,directions,Default.vm <- package match, Default name 041 * 3. about,Default.vm <- stepping up in the hierarchy 042 * 4. Default.vm <- The name configured as default.layout.template 043 * in the corresponding Templating Engine 044 045 * 046 * @author <a href="mailto:hps@intermeta.de">Henning P. Schmiedehausen</a> 047 * @version $Id: LayoutTemplateMapper.java 1071091 2011-02-15 22:06:55Z tv $ 048 */ 049 050 public class LayoutTemplateMapper 051 extends BaseTemplateMapper 052 implements Mapper 053 { 054 /** Logging */ 055 private static Log log = LogFactory.getLog(LayoutTemplateMapper.class); 056 057 /** 058 * Default C'tor. If you use this C'tor, you must use 059 * the bean setter to set the various properties needed for 060 * this mapper before first usage. 061 */ 062 public LayoutTemplateMapper() 063 { 064 // empty 065 } 066 067 /** 068 * Look for a given Template, then try the 069 * defaults until we hit the root. 070 * 071 * @param template The template name. 072 * @return The parsed module name. 073 */ 074 public String doMapping(String template) 075 { 076 log.debug("doMapping(" + template + ")"); 077 // Copy our elements into an array 078 List<String> components 079 = new ArrayList<String>(Arrays.asList(StringUtils.split( 080 template, 081 String.valueOf(TemplateService.TEMPLATE_PARTS_SEPARATOR)))); 082 int componentSize = components.size() - 1 ; 083 084 // This method never gets an empty string passed. 085 // So this is never < 0 086 String templateName = components.get(componentSize); 087 components.remove(componentSize--); 088 089 log.debug("templateName is " + templateName); 090 091 // Last element decides, which template Service to use... 092 TemplateEngineService tes = TurbineTemplate.getTemplateEngineService(templateName); 093 094 if (tes == null) 095 { 096 return null; 097 } 098 099 String defaultName = 100 TurbineTemplate.getDefaultLayoutTemplateName(templateName); // We're, after all, a Layout Template Mapper... 101 102 // This is an optimization. If the name we're looking for is 103 // already the default name for the template, don't do a "first run" 104 // which looks for an exact match. 105 boolean firstRun = !templateName.equals(defaultName); 106 107 for(;;) 108 { 109 String templatePackage = StringUtils.join(components.iterator(), String.valueOf(separator)); 110 111 log.debug("templatePackage is now: " + templatePackage); 112 113 StringBuffer testName = new StringBuffer(); 114 115 if (!components.isEmpty()) 116 { 117 testName.append(templatePackage); 118 testName.append(separator); 119 } 120 121 testName.append((firstRun) 122 ? templateName 123 : defaultName); 124 125 // But the Templating service must look for the name with prefix 126 StringBuffer templatePath = new StringBuffer(); 127 if (StringUtils.isNotEmpty(prefix)) 128 { 129 templatePath.append(prefix); 130 templatePath.append(separator); 131 } 132 templatePath.append(testName); 133 134 log.debug("Looking for " + templatePath); 135 136 if (tes.templateExists(templatePath.toString())) 137 { 138 log.debug("Found it, returning " + testName); 139 return testName.toString(); 140 } 141 142 if (firstRun) 143 { 144 firstRun = false; 145 } 146 else 147 { 148 // We're no longer on the first Run (so we 149 // already tested the "Default" template) 150 // and the package is empty (we've hit the 151 // root. So we now break the endless loop. 152 if (components.isEmpty()) 153 { 154 break; // for(;;) 155 } 156 // We still have components. Remove the 157 // last one and go through the loop again. 158 components.remove(componentSize--); 159 } 160 } 161 162 log.debug("Returning default"); 163 return getDefaultName(template); 164 } 165 }