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1   package org.apache.maven.plugin;
2   
3   /*
4    * Licensed to the Apache Software Foundation (ASF) under one
5    * or more contributor license agreements.  See the NOTICE file
6    * distributed with this work for additional information
7    * regarding copyright ownership.  The ASF licenses this file
8    * to you under the Apache License, Version 2.0 (the
9    * "License"); you may not use this file except in compliance
10   * with the License.  You may obtain a copy of the License at
11   *
12   *  http://www.apache.org/licenses/LICENSE-2.0
13   *
14   * Unless required by applicable law or agreed to in writing,
15   * software distributed under the License is distributed on an
16   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
17   * KIND, either express or implied.  See the License for the
18   * specific language governing permissions and limitations
19   * under the License.
20   */
21  
22  import java.io.File;
23  import java.util.Properties;
24  
25  import org.apache.maven.execution.MavenSession;
26  import org.apache.maven.plugin.descriptor.MojoDescriptor;
27  import org.apache.maven.plugin.descriptor.PluginDescriptor;
28  import org.apache.maven.project.MavenProject;
29  import org.apache.maven.project.path.PathTranslator;
30  import org.codehaus.plexus.component.configurator.expression.ExpressionEvaluationException;
31  import org.codehaus.plexus.component.configurator.expression.TypeAwareExpressionEvaluator;
32  import org.codehaus.plexus.logging.Logger;
33  import org.codehaus.plexus.util.introspection.ReflectionValueExtractor;
34  
35  /**
36   * Evaluator for plugin parameters expressions. Content surrounded by <code>${</code> and <code>}</code> is evaluated.
37   * Recognized values are:<table border="1">
38   * <tr><th>expression</th>                     <th></th>               <th>evaluation result</th></tr>
39   * <tr><td><code>session</code></td>           <td></td>               <td>the actual {@link MavenSession}</td></tr>
40   * <tr><td><code>session.*</code></td>         <td>(since Maven 3)</td><td></td></tr>
41   * <tr><td><code>localRepository</code></td>   <td></td>               <td>{@link MavenSession#getLocalRepository()}</td></tr>
42   * <tr><td><code>reactorProjects</code></td>   <td></td>               <td>{@link MavenSession#getProjects()}</td></tr>
43   * <tr><td><code>repositorySystemSession</code></td><td> (since Maven 3)</td><td>{@link MavenSession#getRepositorySession()}</td></tr>
44   * <tr><td><code>project</code></td>           <td></td>               <td>{@link MavenSession#getCurrentProject()}</td></tr>
45   * <tr><td><code>project.*</code></td>         <td></td>               <td></td></tr>
46   * <tr><td><code>pom.*</code></td>             <td>(since Maven 3)</td><td>same as <code>project.*</code></td></tr>
47   * <tr><td><code>executedProject</code></td>   <td></td>               <td>{@link MavenProject#getExecutionProject()}</td></tr>
48   * <tr><td><code>settings</code></td>          <td></td>               <td>{@link MavenSession#getSettings()}</td></tr>
49   * <tr><td><code>settings.*</code></td>        <td></td>               <td></td></tr>
50   * <tr><td><code>basedir</code></td>           <td></td>               <td>{@link MavenSession#getExecutionRootDirectory()} or <code>System.getProperty( "user.dir" )</code> if null</td></tr>
51   * <tr><td><code>mojoExecution</code></td>     <td></td>               <td>the actual {@link MojoExecution}</td></tr>
52   * <tr><td><code>mojo</code></td>              <td>(since Maven 3)</td><td>same as <code>mojoExecution</code></td></tr>
53   * <tr><td><code>mojo.*</code></td>            <td>(since Maven 3)</td><td></td></tr>
54   * <tr><td><code>plugin</code></td>            <td>(since Maven 3)</td><td>{@link MojoExecution#getMojoDescriptor()}.{@link MojoDescriptor#getPluginDescriptor() getPluginDescriptor()}</td></tr>
55   * <tr><td><code>plugin.*</code></td>          <td></td>               <td></td></tr>
56   * <tr><td><code>*</code></td>                 <td></td>               <td>system properties</td></tr>
57   * <tr><td><code>*</code></td>                 <td></td>               <td>project properties</td></tr>
58   * </table>
59   * <i>Notice:</i> <code>reports</code> was supported in Maven 2.x but was removed in Maven 3
60   * 
61   * @author Jason van Zyl
62   * @see MavenSession
63   * @see MojoExecution
64   */
65  public class PluginParameterExpressionEvaluator
66      implements TypeAwareExpressionEvaluator
67  {
68      private MavenSession session;
69  
70      private MojoExecution mojoExecution;
71  
72      private MavenProject project;
73  
74      private String basedir;
75  
76      private Properties properties;
77  
78      @Deprecated //TODO: used by the Enforcer plugin
79      public PluginParameterExpressionEvaluator( MavenSession session, MojoExecution mojoExecution,
80                                                 PathTranslator pathTranslator, Logger logger, MavenProject project,
81                                                 Properties properties )
82      {
83          this( session, mojoExecution );
84      }
85  
86      public PluginParameterExpressionEvaluator( MavenSession session )
87      {
88          this( session, null );
89      }
90  
91      public PluginParameterExpressionEvaluator( MavenSession session, MojoExecution mojoExecution )
92      {
93          this.session = session;
94          this.mojoExecution = mojoExecution;
95          this.properties = session.getExecutionProperties();
96          this.project = session.getCurrentProject();
97  
98          String basedir = null;
99  
100         if ( project != null )
101         {
102             File projectFile = project.getBasedir();
103 
104             // this should always be the case for non-super POM instances...
105             if ( projectFile != null )
106             {
107                 basedir = projectFile.getAbsolutePath();
108             }
109         }
110 
111         if ( basedir == null )
112         {
113             basedir = session.getExecutionRootDirectory();
114         }
115 
116         if ( basedir == null )
117         {
118             basedir = System.getProperty( "user.dir" );
119         }
120 
121         this.basedir = basedir;
122     }
123 
124     public Object evaluate( String expr )
125         throws ExpressionEvaluationException
126     {
127         return evaluate( expr, null );
128     }
129 
130     public Object evaluate( String expr, Class<?> type )
131         throws ExpressionEvaluationException
132     {
133         Object value = null;
134 
135         if ( expr == null )
136         {
137             return null;
138         }
139 
140         String expression = stripTokens( expr );
141         if ( expression.equals( expr ) )
142         {
143             int index = expr.indexOf( "${" );
144             if ( index >= 0 )
145             {
146                 int lastIndex = expr.indexOf( "}", index );
147                 if ( lastIndex >= 0 )
148                 {
149                     String retVal = expr.substring( 0, index );
150 
151                     if ( ( index > 0 ) && ( expr.charAt( index - 1 ) == '$' ) )
152                     {
153                         retVal += expr.substring( index + 1, lastIndex + 1 );
154                     }
155                     else
156                     {
157                         Object subResult = evaluate( expr.substring( index, lastIndex + 1 ) );
158 
159                         if ( subResult != null )
160                         {
161                             retVal += subResult;
162                         }
163                         else
164                         {
165                             retVal += "$" + expr.substring( index + 1, lastIndex + 1 );
166                         }
167                     }
168 
169                     retVal += evaluate( expr.substring( lastIndex + 1 ) );
170                     return retVal;
171                 }
172             }
173 
174             // Was not an expression
175             if ( expression.contains( "$$" ) )
176             {
177                 return expression.replaceAll( "\\$\\$", "\\$" );
178             }
179             else
180             {
181                 return expression;
182             }
183         }
184 
185         MojoDescriptor mojoDescriptor = mojoExecution.getMojoDescriptor();
186 
187         if ( "localRepository".equals( expression ) )
188         {
189             value = session.getLocalRepository();
190         }
191         else if ( "session".equals( expression ) )
192         {
193             value = session;
194         }
195         else if ( expression.startsWith( "session" ) )
196         {
197             try
198             {
199                 int pathSeparator = expression.indexOf( "/" );
200 
201                 if ( pathSeparator > 0 )
202                 {
203                     String pathExpression = expression.substring( 1, pathSeparator );
204                     value = ReflectionValueExtractor.evaluate( pathExpression, session );
205                     value = value + expression.substring( pathSeparator );
206                 }
207                 else
208                 {
209                     value = ReflectionValueExtractor.evaluate( expression.substring( 1 ), session );
210                 }
211             }
212             catch ( Exception e )
213             {
214                 // TODO: don't catch exception
215                 throw new ExpressionEvaluationException( "Error evaluating plugin parameter expression: " + expression,
216                                                          e );
217             }
218         }
219         else if ( "reactorProjects".equals( expression ) )
220         {
221             value = session.getProjects();
222         }
223         else if ( "mojoExecution".equals( expression ) )
224         {
225             value = mojoExecution;
226         }
227         else if ( "project".equals( expression ) )
228         {
229             value = project;
230         }
231         else if ( "executedProject".equals( expression ) )
232         {
233             value = project.getExecutionProject();
234         }
235         else if ( expression.startsWith( "project" ) || expression.startsWith( "pom" ) )
236         {
237             try
238             {
239                 int pathSeparator = expression.indexOf( "/" );
240 
241                 if ( pathSeparator > 0 )
242                 {
243                     String pathExpression = expression.substring( 0, pathSeparator );
244                     value = ReflectionValueExtractor.evaluate( pathExpression, project );
245                     value = value + expression.substring( pathSeparator );
246                 }
247                 else
248                 {
249                     value = ReflectionValueExtractor.evaluate( expression.substring( 1 ), project );
250                 }
251             }
252             catch ( Exception e )
253             {
254                 // TODO: don't catch exception
255                 throw new ExpressionEvaluationException( "Error evaluating plugin parameter expression: " + expression,
256                                                          e );
257             }
258         }
259         else if ( expression.equals( "repositorySystemSession" ) )
260         {
261             value = session.getRepositorySession();
262         }
263         else if ( expression.equals( "mojo" ) )
264         {
265             value = mojoExecution;
266         }
267         else if ( expression.startsWith( "mojo" ) )
268         {
269             try
270             {
271                 int pathSeparator = expression.indexOf( "/" );
272 
273                 if ( pathSeparator > 0 )
274                 {
275                     String pathExpression = expression.substring( 1, pathSeparator );
276                     value = ReflectionValueExtractor.evaluate( pathExpression, mojoExecution );
277                     value = value + expression.substring( pathSeparator );
278                 }
279                 else
280                 {
281                     value = ReflectionValueExtractor.evaluate( expression.substring( 1 ), mojoExecution );
282                 }
283             }
284             catch ( Exception e )
285             {
286                 // TODO: don't catch exception
287                 throw new ExpressionEvaluationException( "Error evaluating plugin parameter expression: " + expression,
288                                                          e );
289             }
290         }
291         else if ( expression.equals( "plugin" ) )
292         {
293             value = mojoDescriptor.getPluginDescriptor();
294         }
295         else if ( expression.startsWith( "plugin" ) )
296         {
297             try
298             {
299                 int pathSeparator = expression.indexOf( "/" );
300 
301                 PluginDescriptor pluginDescriptor = mojoDescriptor.getPluginDescriptor();
302 
303                 if ( pathSeparator > 0 )
304                 {
305                     String pathExpression = expression.substring( 1, pathSeparator );
306                     value = ReflectionValueExtractor.evaluate( pathExpression, pluginDescriptor );
307                     value = value + expression.substring( pathSeparator );
308                 }
309                 else
310                 {
311                     value = ReflectionValueExtractor.evaluate( expression.substring( 1 ), pluginDescriptor );
312                 }
313             }
314             catch ( Exception e )
315             {
316                 throw new ExpressionEvaluationException( "Error evaluating plugin parameter expression: " + expression,
317                                                          e );
318             }
319         }
320         else if ( "settings".equals( expression ) )
321         {
322             value = session.getSettings();
323         }
324         else if ( expression.startsWith( "settings" ) )
325         {
326             try
327             {
328                 int pathSeparator = expression.indexOf( "/" );
329 
330                 if ( pathSeparator > 0 )
331                 {
332                     String pathExpression = expression.substring( 1, pathSeparator );
333                     value = ReflectionValueExtractor.evaluate( pathExpression, session.getSettings() );
334                     value = value + expression.substring( pathSeparator );
335                 }
336                 else
337                 {
338                     value = ReflectionValueExtractor.evaluate( expression.substring( 1 ), session.getSettings() );
339                 }
340             }
341             catch ( Exception e )
342             {
343                 // TODO: don't catch exception
344                 throw new ExpressionEvaluationException( "Error evaluating plugin parameter expression: " + expression,
345                                                          e );
346             }
347         }
348         else if ( "basedir".equals( expression ) )
349         {
350             value = basedir;
351         }
352         else if ( expression.startsWith( "basedir" ) )
353         {
354             int pathSeparator = expression.indexOf( "/" );
355 
356             if ( pathSeparator > 0 )
357             {
358                 value = basedir + expression.substring( pathSeparator );
359             }
360         }
361 
362         /*
363          * MNG-4312: We neither have reserved all of the above magic expressions nor is their set fixed/well-known (it
364          * gets occasionally extended by newer Maven versions). This imposes the risk for existing plugins to
365          * unintentionally use such a magic expression for an ordinary system property. So here we check whether we
366          * ended up with a magic value that is not compatible with the type of the configured mojo parameter (a string
367          * could still be converted by the configurator so we leave those alone). If so, back off to evaluating the
368          * expression from properties only.
369          */
370         if ( value != null && type != null && !( value instanceof String ) && !isTypeCompatible( type, value ) )
371         {
372             value = null;
373         }
374 
375         if ( value == null )
376         {
377             // The CLI should win for defining properties
378 
379             if ( properties != null )
380             {
381                 // We will attempt to get nab a system property as a way to specify a
382                 // parameter to a plugins. My particular case here is allowing the surefire
383                 // plugin to run a single test so I want to specify that class on the cli
384                 // as a parameter.
385 
386                 value = properties.getProperty( expression );
387             }
388 
389             if ( ( value == null ) && ( ( project != null ) && ( project.getProperties() != null ) ) )
390             {
391                 value = project.getProperties().getProperty( expression );
392             }
393 
394         }
395 
396         if ( value instanceof String )
397         {
398             // TODO: without #, this could just be an evaluate call...
399 
400             String val = (String) value;
401 
402             int exprStartDelimiter = val.indexOf( "${" );
403 
404             if ( exprStartDelimiter >= 0 )
405             {
406                 if ( exprStartDelimiter > 0 )
407                 {
408                     value = val.substring( 0, exprStartDelimiter ) + evaluate( val.substring( exprStartDelimiter ) );
409                 }
410                 else
411                 {
412                     value = evaluate( val.substring( exprStartDelimiter ) );
413                 }
414             }
415         }
416 
417         return value;
418     }
419 
420     private static boolean isTypeCompatible( Class<?> type, Object value )
421     {
422         if ( type.isInstance( value ) )
423         {
424             return true;
425         }
426         // likely Boolean -> boolean, Short -> int etc. conversions, it's not the problem case we try to avoid
427         return ( ( type.isPrimitive() || type.getName().startsWith( "java.lang." ) )
428                         && value.getClass().getName().startsWith( "java.lang." ) );
429     }
430 
431     private String stripTokens( String expr )
432     {
433         if ( expr.startsWith( "${" ) && ( expr.indexOf( "}" ) == expr.length() - 1 ) )
434         {
435             expr = expr.substring( 2, expr.length() - 1 );
436         }
437         return expr;
438     }
439 
440     public File alignToBaseDirectory( File file )
441     {
442         // TODO: Copied from the DefaultInterpolator. We likely want to resurrect the PathTranslator or at least a
443         // similar component for re-usage
444         if ( file != null )
445         {
446             if ( file.isAbsolute() )
447             {
448                 // path was already absolute, just normalize file separator and we're done
449             }
450             else if ( file.getPath().startsWith( File.separator ) )
451             {
452                 // drive-relative Windows path, don't align with project directory but with drive root
453                 file = file.getAbsoluteFile();
454             }
455             else
456             {
457                 // an ordinary relative path, align with project directory
458                 file = new File( new File( basedir, file.getPath() ).toURI().normalize() ).getAbsoluteFile();
459             }
460         }
461         return file;
462     }
463 
464 }