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 is a pretty simple mapper which returns template pathes for
037 * a supplied template name. If the path does not exist, it looks for
038 * a templated called "Default" in the same package.
039 * This path can be used by the TemplateEngine to access
040 * a certain resource to actually render the template.
041 *
042 * @author <a href="mailto:hps@intermeta.de">Henning P. Schmiedehausen</a>
043 * @version $Id: ScreenDefaultTemplateMapper.java 1071091 2011-02-15 22:06:55Z tv $
044 */
045
046 public class ScreenDefaultTemplateMapper
047 extends BaseTemplateMapper
048 implements Mapper
049 {
050 /** Logging */
051 private static Log log = LogFactory.getLog(ScreenDefaultTemplateMapper.class);
052
053 /**
054 * Default C'tor. If you use this C'tor, you must use
055 * the bean setter to set the various properties needed for
056 * this mapper before first usage.
057 */
058 public ScreenDefaultTemplateMapper()
059 {
060 // empty
061 }
062
063 /**
064 * Look for a given Template, then try the
065 * default.
066 *
067 * @param template The template name.
068 * @return The parsed module name.
069 */
070 public String doMapping(String template)
071 {
072 log.debug("doMapping(" + template + ")");
073 // Copy our elements into an array
074 List<String> components
075 = new ArrayList<String>(Arrays.asList(StringUtils.split(
076 template,
077 String.valueOf(TemplateService.TEMPLATE_PARTS_SEPARATOR))));
078 int componentSize = components.size() - 1 ;
079
080 // This method never gets an empty string passed.
081 // So this is never < 0
082 String templateName = components.get(componentSize);
083 components.remove(componentSize--);
084
085 log.debug("templateName is " + templateName);
086
087 // Last element decides, which template Service to use...
088 TemplateEngineService tes = TurbineTemplate.getTemplateEngineService(templateName);
089
090 if (tes == null)
091 {
092 return null;
093 }
094
095 String defaultName = "Default.vm";
096
097 // This is an optimization. If the name we're looking for is
098 // already the default name for the template, don't do a "first run"
099 // which looks for an exact match.
100 boolean firstRun = !templateName.equals(defaultName);
101
102 for(;;)
103 {
104 String templatePackage = StringUtils.join(components.iterator(), String.valueOf(separator));
105
106 log.debug("templatePackage is now: " + templatePackage);
107
108 StringBuffer testName = new StringBuffer();
109
110 if (!components.isEmpty())
111 {
112 testName.append(templatePackage);
113 testName.append(separator);
114 }
115
116 testName.append((firstRun)
117 ? templateName
118 : defaultName);
119
120 // But the Templating service must look for the name with prefix
121 StringBuffer templatePath = new StringBuffer();
122 if (StringUtils.isNotEmpty(prefix))
123 {
124 templatePath.append(prefix);
125 templatePath.append(separator);
126 }
127 templatePath.append(testName);
128
129 log.debug("Looking for " + templatePath);
130
131 if (tes.templateExists(templatePath.toString()))
132 {
133 log.debug("Found it, returning " + testName);
134 return testName.toString();
135 }
136
137 if (firstRun)
138 {
139 firstRun = false;
140 }
141 else
142 {
143 // We run this loop only two times. The
144 // first time with the 'real' name and the
145 // second time with "Default". The second time
146 // we will end up here and break the for(;;) loop.
147 break;
148 }
149 }
150
151 log.debug("Returning default");
152 return getDefaultName(template);
153 }
154 }