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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.lang3.StringUtils;
29  import org.apache.logging.log4j.LogManager;
30  import org.apache.logging.log4j.Logger;
31  import org.apache.turbine.modules.Assembler;
32  import org.apache.turbine.modules.Loader;
33  import org.apache.turbine.services.template.TemplateService;
34  import org.apache.turbine.util.TurbineException;
35  
36  /**
37   * This mapper tries to map Template names to class names. If no direct match
38   * is found, it tries matches "upwards" in the package hierarchy until either
39   * a match is found or the root is hit. Then it returns the name of the
40   * default class from the TemplateEngineService.
41   *
42   * 1. about.directions.Driving     <- direct matching the template to the class name
43   * 2. about.directions.Default     <- matching the package, class name is Default
44   * 3. about.Default                <- stepping up in the package hierarchy, looking for Default
45   * 4. Default                      <- Class called "Default" without package
46   * 5. VelocityScreen               <- The class configured by the Service (VelocityService) to
47   *
48   * Please note, that no actual packages are searched. This is the scope of the
49   * TemplateEngine Loader which is passed at construction time.
50   *
51   * @author <a href="mailto:hps@intermeta.de">Henning P. Schmiedehausen</a>
52   * @version $Id: ClassMapper.java 1854688 2019-03-03 10:36:42Z tv $
53   */
54  
55  public class ClassMapper
56      extends BaseMapper
57      implements Mapper
58  {
59      /** The loader for actually trying out the package names */
60      private Loader<? extends Assembler> loader = null;
61  
62      /** Logging */
63      private static final Logger log = LogManager.getLogger(ClassMapper.class);
64  
65      /**
66       * Default C'tor. If you use this C'tor, you must use
67       * the bean setter to set the various properties needed for
68       * this mapper before first usage.
69       */
70      public ClassMapper()
71      {
72      	// empty
73      }
74  
75      /**
76       * Get the Loader value.
77       * @return the Loader value.
78       */
79      public Loader<? extends Assembler> getLoader()
80      {
81          return loader;
82      }
83  
84      /**
85       * Set the Loader value.
86       * @param loader The new Loader value.
87       */
88      public void setLoader(Loader<? extends Assembler> loader)
89      {
90          this.loader = loader;
91          log.debug("Loader is {}", this.loader);
92      }
93  
94      /**
95       * Strip off a possible extension, replace all "," with "."
96       * Look through the given package path until a match is found.
97       *
98       * @param template The template name.
99       * @return A class name for the given template.
100      */
101     @Override
102 	public String doMapping(String template)
103     {
104         log.debug("doMapping({})", template);
105 
106         // Copy our elements into an array
107         List<String> components
108             = new ArrayList<String>(Arrays.asList(StringUtils.split(
109                                               template,
110                                               String.valueOf(TemplateService.TEMPLATE_PARTS_SEPARATOR))));
111         int componentSize = components.size() - 1 ;
112 
113         // This method never gets an empty string passed.
114         // So this is never < 0
115         String className = components.get(componentSize);
116         components.remove(componentSize--);
117 
118         log.debug("className is {}", className);
119 
120         // Strip off a possible Extension
121         int dotIndex = className.lastIndexOf(TemplateService.EXTENSION_SEPARATOR);
122         className = (dotIndex < 0) ? className : className.substring(0, dotIndex);
123 
124         // This is an optimization. If the name we're looking for is
125         // already the default name for the template, don't do a "first run"
126         // which looks for an exact match.
127         boolean firstRun = !className.equals(TemplateService.DEFAULT_NAME);
128 
129         for(;;)
130         {
131             String pkg = StringUtils.join(components.iterator(), String.valueOf(separator));
132             StringBuilder testName = new StringBuilder();
133 
134             log.debug("classPackage is now: {}", pkg);
135 
136             if (!components.isEmpty())
137             {
138                 testName.append(pkg);
139                 testName.append(separator);
140             }
141 
142             testName.append((firstRun)
143                 ? className
144                 : TemplateService.DEFAULT_NAME);
145 
146             log.debug("Looking for {}", testName);
147             try
148             {
149                 loader.getAssembler(testName.toString());
150                 log.debug("Found it, returning {}", testName);
151                 return testName.toString();
152             }
153             catch (TurbineException e)
154             {
155                 log.error("Turbine Exception Class mapping", e);
156             }
157             catch (Exception e)
158             {
159                 // Not found. Go on.
160             }
161 
162             if (firstRun)
163             {
164                 firstRun = false;
165             }
166             else
167             {
168                 if (components.isEmpty())
169                 {
170                     break; // for(;;)
171                 }
172                 components.remove(componentSize--);
173             }
174         }
175 
176         log.debug("Returning default");
177         return getDefaultName(template);
178     }
179 }
180 
181 
182 
183