1 package org.apache.turbine.services.template.mapper;
2
3
4 /*
5 * Licensed to the Apache Software Foundation (ASF) under one
6 * or more contributor license agreements. See the NOTICE file
7 * distributed with this work for additional information
8 * regarding copyright ownership. The ASF licenses this file
9 * to you under the Apache License, Version 2.0 (the
10 * "License"); you may not use this file except in compliance
11 * with the License. You may obtain a copy of the License at
12 *
13 * http://www.apache.org/licenses/LICENSE-2.0
14 *
15 * Unless required by applicable law or agreed to in writing,
16 * software distributed under the License is distributed on an
17 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
18 * KIND, either express or implied. See the License for the
19 * specific language governing permissions and limitations
20 * under the License.
21 */
22
23
24 import java.util.ArrayList;
25 import java.util.Arrays;
26 import java.util.List;
27
28 import org.apache.commons.lang.StringUtils;
29 import org.apache.commons.logging.Log;
30 import org.apache.commons.logging.LogFactory;
31 import org.apache.turbine.services.TurbineServices;
32 import org.apache.turbine.services.template.TemplateEngineService;
33 import org.apache.turbine.services.template.TemplateService;
34
35 /**
36 * This mapper is responsible for the lookup of templates for the Layout
37 * It tries to look in various packages for a match:
38 *
39 * 1. about,directions,Driving.vm <- exact match
40 * 2. about,directions,Default.vm <- package match, Default name
41 * 3. about,Default.vm <- stepping up in the hierarchy
42 * 4. Default.vm <- The name configured as default.layout.template
43 * in the corresponding Templating Engine
44
45 *
46 * @author <a href="mailto:hps@intermeta.de">Henning P. Schmiedehausen</a>
47 * @version $Id: LayoutTemplateMapper.java 1723699 2016-01-08 11:29:21Z tv $
48 */
49
50 public class LayoutTemplateMapper
51 extends BaseTemplateMapper
52 implements Mapper
53 {
54 /** Logging */
55 private static Log log = LogFactory.getLog(LayoutTemplateMapper.class);
56
57 /**
58 * Default C'tor. If you use this C'tor, you must use
59 * the bean setter to set the various properties needed for
60 * this mapper before first usage.
61 */
62 public LayoutTemplateMapper()
63 {
64 // empty
65 }
66
67 /**
68 * Look for a given Template, then try the
69 * defaults until we hit the root.
70 *
71 * @param template The template name.
72 * @return The parsed module name.
73 */
74 @Override
75 public String doMapping(String template)
76 {
77 log.debug("doMapping(" + template + ")");
78 // Copy our elements into an array
79 List<String> components
80 = new ArrayList<String>(Arrays.asList(StringUtils.split(
81 template,
82 String.valueOf(TemplateService.TEMPLATE_PARTS_SEPARATOR))));
83 int componentSize = components.size() - 1 ;
84
85 // This method never gets an empty string passed.
86 // So this is never < 0
87 String templateName = components.get(componentSize);
88 components.remove(componentSize--);
89
90 log.debug("templateName is " + templateName);
91
92 // Last element decides, which template Service to use...
93 TemplateService templateService = (TemplateService)TurbineServices.getInstance().getService(TemplateService.SERVICE_NAME);
94 TemplateEngineService tes = templateService.getTemplateEngineService(templateName);
95
96 if (tes == null)
97 {
98 return null;
99 }
100
101 // We're, after all, a Layout Template Mapper...
102 String defaultName = templateService.getDefaultLayoutTemplateName(templateName);
103
104 // This is an optimization. If the name we're looking for is
105 // already the default name for the template, don't do a "first run"
106 // which looks for an exact match.
107 boolean firstRun = !templateName.equals(defaultName);
108
109 for(;;)
110 {
111 String templatePackage = StringUtils.join(components.iterator(), String.valueOf(separator));
112
113 log.debug("templatePackage is now: " + templatePackage);
114
115 StringBuilder testName = new StringBuilder();
116
117 if (!components.isEmpty())
118 {
119 testName.append(templatePackage);
120 testName.append(separator);
121 }
122
123 testName.append((firstRun)
124 ? templateName
125 : defaultName);
126
127 // But the Templating service must look for the name with prefix
128 StringBuilder templatePath = new StringBuilder();
129 if (StringUtils.isNotEmpty(prefix))
130 {
131 templatePath.append(prefix);
132 templatePath.append(separator);
133 }
134 templatePath.append(testName);
135
136 log.debug("Looking for " + templatePath);
137
138 if (tes.templateExists(templatePath.toString()))
139 {
140 log.debug("Found it, returning " + testName);
141 return testName.toString();
142 }
143
144 if (firstRun)
145 {
146 firstRun = false;
147 }
148 else
149 {
150 // We're no longer on the first Run (so we
151 // already tested the "Default" template)
152 // and the package is empty (we've hit the
153 // root. So we now break the endless loop.
154 if (components.isEmpty())
155 {
156 break; // for(;;)
157 }
158 // We still have components. Remove the
159 // last one and go through the loop again.
160 components.remove(componentSize--);
161 }
162 }
163
164 log.debug("Returning default");
165 return getDefaultName(template);
166 }
167 }