package org.apache.maven.plugins.checkstyle;
   
   /*
    * Licensed to the Apache Software Foundation (ASF) under one
    * or more contributor license agreements.  See the NOTICE file
    * distributed with this work for additional information
    * regarding copyright ownership.  The ASF licenses this file
    * to you under the Apache License, Version 2.0 (the
    * "License"); you may not use this file except in compliance
   * with the License.  You may obtain a copy of the License at
   *
   *   http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing,
   * software distributed under the License is distributed on an
   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
   * KIND, either express or implied.  See the License for the
   * specific language governing permissions and limitations
   * under the License.
   */
  
  import java.io.ByteArrayOutputStream;
  import java.io.File;
  import java.io.FileNotFoundException;
  import java.io.FileOutputStream;
  import java.io.IOException;
  import java.io.OutputStream;
  import java.util.ArrayList;
  import java.util.Calendar;
  import java.util.List;
  import java.util.Locale;
  import java.util.Map;
  import java.util.ResourceBundle;
  
  import org.apache.maven.artifact.Artifact;
  import org.apache.maven.execution.MavenSession;
  import org.apache.maven.model.Dependency;
  import org.apache.maven.model.Plugin;
  import org.apache.maven.model.PluginManagement;
  import org.apache.maven.model.ReportPlugin;
  import org.apache.maven.model.Resource;
  import org.apache.maven.plugin.descriptor.PluginDescriptor;
  import org.apache.maven.plugins.annotations.Component;
  import org.apache.maven.plugins.annotations.Parameter;
  import org.apache.maven.plugins.checkstyle.exec.CheckstyleExecutor;
  import org.apache.maven.plugins.checkstyle.exec.CheckstyleExecutorException;
  import org.apache.maven.plugins.checkstyle.exec.CheckstyleExecutorRequest;
  import org.apache.maven.plugins.checkstyle.exec.CheckstyleResults;
  import org.apache.maven.plugins.checkstyle.rss.CheckstyleRssGenerator;
  import org.apache.maven.plugins.checkstyle.rss.CheckstyleRssGeneratorRequest;
  import org.apache.maven.reporting.AbstractMavenReport;
  import org.apache.maven.reporting.MavenReportException;
  import org.codehaus.plexus.configuration.PlexusConfiguration;
  import org.codehaus.plexus.resource.ResourceManager;
  import org.codehaus.plexus.resource.loader.FileResourceLoader;
  import org.codehaus.plexus.util.FileUtils;
  import org.codehaus.plexus.util.PathTool;
  import org.codehaus.plexus.util.StringUtils;
  
  import com.puppycrawl.tools.checkstyle.DefaultLogger;
  import com.puppycrawl.tools.checkstyle.XMLLogger;
  import com.puppycrawl.tools.checkstyle.api.AuditListener;
  import com.puppycrawl.tools.checkstyle.api.AutomaticBean.OutputStreamOptions;
  import com.puppycrawl.tools.checkstyle.api.CheckstyleException;
  
  /**
   * Base abstract class for Checkstyle reports.
   *
   *
   */
  public abstract class AbstractCheckstyleReport
      extends AbstractMavenReport
  {
      public static final String PLUGIN_RESOURCES = "org/apache/maven/plugins/checkstyle";
  
      protected static final String JAVA_FILES = "**\\/*.java";
  
      private static final String DEFAULT_CONFIG_LOCATION = "sun_checks.xml";
  
      @Parameter( defaultValue = "${session}", readonly = true, required = true )
      private MavenSession session;
  
      /**
       * Specifies the cache file used to speed up Checkstyle on successive runs.
       */
      @Parameter( defaultValue = "${project.build.directory}/checkstyle-cachefile" )
      protected String cacheFile;
  
      /**
       * <p>
       * Specifies the location of the XML configuration to use.
       * <p>
       * Potential values are a filesystem path, a URL, or a classpath resource.
       * This parameter expects that the contents of the location conform to the
       * xml format (Checkstyle <a
       * href="https://checkstyle.org/config.html#Modules">Checker
       * module</a>) configuration of rulesets.
       * <p>
       * This parameter is resolved as resource, URL, then file. If successfully
      * resolved, the contents of the configuration is copied into the
      * <code>${project.build.directory}/checkstyle-configuration.xml</code>
      * file before being passed to Checkstyle as a configuration.
      * <p>
      * There are 2 predefined rulesets included in Maven Checkstyle Plugin:
      * <ul>
      * <li><code>sun_checks.xml</code>: Sun Checks.</li>
      * <li><code>google_checks.xml</code>: Google Checks.</li>
      * </ul>
      */
     @Parameter( property = "checkstyle.config.location", defaultValue = DEFAULT_CONFIG_LOCATION )
     protected String configLocation;
 
     /**
      * Output errors to console.
      */
     @Parameter( property = "checkstyle.consoleOutput", defaultValue = "false" )
     protected boolean consoleOutput;
 
     /**
      * Specifies if the build should fail upon a violation.
      */
     @Parameter( defaultValue = "false" )
     protected boolean failsOnError;
 
     /**
      * <p>
      * Specifies the location of the License file (a.k.a. the header file) that
      * can be used by Checkstyle to verify that source code has the correct
      * license header.
      * <p>
      * You need to use <code>${checkstyle.header.file}</code> in your Checkstyle xml
      * configuration to reference the name of this header file.
      * <p>
      * For instance:
      * <pre>
      * &lt;module name="RegexpHeader"&gt;
      *   &lt;property name="headerFile" value="${checkstyle.header.file}"/&gt;
      * &lt;/module&gt;
      * </pre>
      *
      * @since 2.0-beta-2
      */
     @Parameter( property = "checkstyle.header.file", defaultValue = "LICENSE.txt" )
     protected String headerLocation;
 
     /**
      * Skip entire check.
      *
      * @since 2.2
      */
     @Parameter( property = "checkstyle.skip", defaultValue = "false" )
     protected boolean skip;
 
     /**
      * Specifies the path and filename to save the Checkstyle output. The format
      * of the output file is determined by the <code>outputFileFormat</code>
      * parameter.
      */
     @Parameter( property = "checkstyle.output.file", defaultValue = "${project.build.directory}/checkstyle-result.xml" )
     private File outputFile;
 
     /**
      * <p>
      * Specifies the location of the properties file.
      * <p>
      * This parameter is resolved as URL, File then resource. If successfully
      * resolved, the contents of the properties location is copied into the
      * <code>${project.build.directory}/checkstyle-checker.properties</code>
      * file before being passed to Checkstyle for loading.
      * <p>
      * The contents of the <code>propertiesLocation</code> will be made
      * available to Checkstyle for specifying values for parameters within the
      * xml configuration (specified in the <code>configLocation</code>
      * parameter).
      *
      * @since 2.0-beta-2
      */
     @Parameter( property = "checkstyle.properties.location" )
     protected String propertiesLocation;
 
     /**
      * Allows for specifying raw property expansion information.
      */
     @Parameter
     protected String propertyExpansion;
 
     /**
      * Specifies the location of the resources to be used for Checkstyle.
      *
      * @since 2.10
      */
     @Parameter( defaultValue = "${project.resources}", readonly = true )
     protected List<Resource> resources;
 
     /**
      * Specifies the location of the test resources to be used for Checkstyle.
      *
      * @since 2.11
      */
     @Parameter( defaultValue = "${project.testResources}", readonly = true )
     protected List<Resource> testResources;
 
     /**
      * Specifies the names filter of the source files to be used for Checkstyle.
      */
     @Parameter( property = "checkstyle.includes", defaultValue = JAVA_FILES, required = true )
     protected String includes;
 
     /**
      * Specifies the names filter of the source files to be excluded for
      * Checkstyle.
      */
     @Parameter( property = "checkstyle.excludes" )
     protected String excludes;
 
     /**
      * Specifies the names filter of the resource files to be used for Checkstyle.
      * @since 2.11
      */
     @Parameter( property = "checkstyle.resourceIncludes", defaultValue = "**/*.properties", required = true )
     protected String resourceIncludes;
 
     /**
      * Specifies the names filter of the resource files to be excluded for
      * Checkstyle.
      * @since 2.11
      */
     @Parameter( property = "checkstyle.resourceExcludes" )
     protected String resourceExcludes;
 
     /**
      * Specifies whether to include the resource directories in the check.
      * @since 2.11
      */
     @Parameter( property = "checkstyle.includeResources", defaultValue = "true", required = true )
     protected boolean includeResources;
 
     /**
      * Specifies whether to include the test resource directories in the check.
      * @since 2.11
      */
     @Parameter( property = "checkstyle.includeTestResources", defaultValue = "true", required = true )
     protected boolean includeTestResources;
 
     /**
      * Specifies the location of the source directory to be used for Checkstyle.
      *
      * @deprecated instead use {@link #sourceDirectories}. For version 3.0.0, this parameter is only defined to break
      *             the build if you use it!
      */
     @Deprecated
     @Parameter
     private File sourceDirectory;
 
     /**
      * Specifies the location of the source directories to be used for Checkstyle.
      * Default value is <code>${project.compileSourceRoots}</code>.
      * @since 2.13
      */
     // Compatibility with all Maven 3: default of 'project.compileSourceRoots' is done manually because of MNG-5440
     @Parameter
     private List<String> sourceDirectories;
 
     /**
      * Specifies the location of the test source directory to be used for Checkstyle.
      *
      * @since 2.2
      * @deprecated instead use {@link #testSourceDirectories}. For version 3.0.0, this parameter is only defined to
      *             break the build if you use it!
      */
     @Parameter
     @Deprecated
     private File testSourceDirectory;
 
     /**
      * Specifies the location of the test source directories to be used for Checkstyle.
      * Default value is <code>${project.testCompileSourceRoots}</code>.
      * @since 2.13
      */
     // Compatibility with all Maven 3: default of 'project.testCompileSourceRoots' is done manually because of MNG-5440
     @Parameter
     private List<String> testSourceDirectories;
 
     /**
      * Include or not the test source directory/directories to be used for Checkstyle.
      *
      * @since 2.2
      */
     @Parameter( defaultValue = "false" )
     protected boolean includeTestSourceDirectory;
 
     /**
      * The key to be used in the properties for the suppressions file.
      *
      * @since 2.1
      */
     @Parameter( property = "checkstyle.suppression.expression", defaultValue = "checkstyle.suppressions.file" )
     protected String suppressionsFileExpression;
 
     /**
      * <p>
      * Specifies the location of the suppressions XML file to use.
      * <p>
      * This parameter is resolved as resource, URL, then file. If successfully
      * resolved, the contents of the suppressions XML is copied into the
      * <code>${project.build.directory}/checkstyle-supressions.xml</code> file
      * before being passed to Checkstyle for loading.
      * <p>
      * See <code>suppressionsFileExpression</code> for the property that will
      * be made available to your Checkstyle configuration.
      *
      * @since 2.0-beta-2
      */
     @Parameter( property = "checkstyle.suppressions.location" )
     protected String suppressionsLocation;
 
     /**
      * If <code>null</code>, the Checkstyle plugin will display violations on stdout.
      * Otherwise, a text file will be created with the violations.
      */
     @Parameter
     private File useFile;
 
     /**
      * Specifies the format of the output to be used when writing to the output
      * file. Valid values are "<code>plain</code>" and "<code>xml</code>".
      */
     @Parameter( property = "checkstyle.output.format", defaultValue = "xml" )
     private String outputFileFormat;
 
     /**
      * Specifies if the Rules summary should be enabled or not.
      */
     @Parameter( property = "checkstyle.enable.rules.summary", defaultValue = "true" )
     private boolean enableRulesSummary;
 
     /**
      * Specifies if the Severity summary should be enabled or not.
      */
     @Parameter( property = "checkstyle.enable.severity.summary", defaultValue = "true" )
     private boolean enableSeveritySummary;
 
     /**
      * Specifies if the Files summary should be enabled or not.
      */
     @Parameter( property = "checkstyle.enable.files.summary", defaultValue = "true" )
     private boolean enableFilesSummary;
 
     /**
      * Specifies if the RSS should be enabled or not.
      *
      * @deprecated This feature will be removed in a future version.
      */
     @Parameter( property = "checkstyle.enable.rss", defaultValue = "false" )
     @Deprecated
     private boolean enableRSS;
 
     /**
      * The Plugin Descriptor
      */
     @Parameter( defaultValue = "${plugin}", readonly = true, required = true )
     private PluginDescriptor plugin;
 
     /**
      * Link the violation line numbers to the source xref. Will link
      * automatically if Maven JXR plugin is being used.
      *
      * @since 2.1
      */
     @Parameter( property = "linkXRef", defaultValue = "true" )
     private boolean linkXRef;
 
     /**
      * Location of the Xrefs to link to.
      */
     @Parameter( defaultValue = "${project.reporting.outputDirectory}/xref" )
     private File xrefLocation;
 
     /**
      * Location of the XrefTests to link to.
      */
     @Parameter( defaultValue = "${project.reporting.outputDirectory}/xref-test" )
     private File xrefTestLocation;
 
     /**
      * When using custom treeWalkers, specify their names here so the checks
      * inside the treeWalker end up the the rule-summary.
      *
      * @since 2.11
      */
     @Parameter
     private List<String> treeWalkerNames;
 
     /**
      * Specifies whether modules with a configured severity of <code>ignore</code> should be omitted during Checkstyle
      * invocation.
      *
      * @since 3.0.0
      */
     @Parameter( defaultValue = "false" )
     private boolean omitIgnoredModules;
 
     /**
      * By using this property, you can specify the whole Checkstyle rules
      * inline directly inside this pom.
      *
      * <pre>
      * &lt;plugin&gt;
      *   ...
      *   &lt;configuration&gt;
      *     &lt;checkstyleRules&gt;
      *       &lt;module name="Checker"&gt;
      *         &lt;module name="FileTabCharacter"&gt;
      *           &lt;property name="eachLine" value="true" /&gt;
      *         &lt;/module&gt;
      *         &lt;module name="TreeWalker"&gt;
      *           &lt;module name="EmptyBlock"/&gt;
      *         &lt;/module&gt;
      *       &lt;/module&gt;
      *     &lt;/checkstyleRules&gt;
      *   &lt;/configuration&gt;
      *   ...
      * </pre>
      *
      * @since 2.12
      */
     @Parameter
     private PlexusConfiguration checkstyleRules;
 
     /**
      * Dump file for inlined Checkstyle rules.
      */
     @Parameter( property = "checkstyle.output.rules.file",
                     defaultValue = "${project.build.directory}/checkstyle-rules.xml" )
     private File rulesFiles;
 
     /**
      * The header to use for the inline configuration.
      * Only used when you specify {@code checkstyleRules}.
      */
     @Parameter( defaultValue = "<?xml version=\"1.0\"?>\n"
             + "<!DOCTYPE module PUBLIC \"-//Checkstyle//DTD Checkstyle Configuration 1.3//EN\"\n"
             + "        \"https://checkstyle.org/dtds/configuration_1_3.dtd\">\n" )
     private String checkstyleRulesHeader;
 
     /**
      */
     @Component
     protected ResourceManager locator;
 
     /**
      * CheckstyleRssGenerator.
      *
      * @since 2.4
      */
     @Component( role = CheckstyleRssGenerator.class, hint = "default" )
     @Deprecated
     protected CheckstyleRssGenerator checkstyleRssGenerator;
 
     /**
      * @since 2.5
      */
     @Component( role = CheckstyleExecutor.class, hint = "default" )
     protected CheckstyleExecutor checkstyleExecutor;
 
     protected ByteArrayOutputStream stringOutputStream;
 
     /** {@inheritDoc} */
     public String getName( Locale locale )
     {
         return getBundle( locale ).getString( "report.checkstyle.name" );
     }
 
     /** {@inheritDoc} */
     public String getDescription( Locale locale )
     {
         return getBundle( locale ).getString( "report.checkstyle.description" );
     }
 
     /** {@inheritDoc} */
     public void executeReport( Locale locale )
         throws MavenReportException
     {
         checkDeprecatedParameterUsage( sourceDirectory, "sourceDirectory", "sourceDirectories" );
         checkDeprecatedParameterUsage( testSourceDirectory, "testSourceDirectory", "testSourceDirectories" );
 
         locator.addSearchPath( FileResourceLoader.ID, project.getFile().getParentFile().getAbsolutePath() );
         locator.addSearchPath( "url", "" );
 
         locator.setOutputDirectory( new File( project.getBuild().getDirectory() ) );
 
         // for when we start using maven-shared-io and maven-shared-monitor...
         // locator = new Locator( new MojoLogMonitorAdaptor( getLog() ) );
 
         // locator = new Locator( getLog(), new File( project.getBuild().getDirectory() ) );
         if ( checkstyleRules != null )
         {
             if ( !DEFAULT_CONFIG_LOCATION.equals( configLocation ) )
             {
                 throw new MavenReportException( "If you use inline configuration for rules, don't specify "
                         + "a configLocation" );
             }
             if ( checkstyleRules.getChildCount() > 1 )
             {
                 throw new MavenReportException( "Currently only one root module is supported" );
             }
             PlexusConfiguration checkerModule = checkstyleRules.getChild( 0 );
 
             try
             {
                 FileUtils.forceMkdir( rulesFiles.getParentFile() );
                 FileUtils.fileWrite( rulesFiles, checkstyleRulesHeader + checkerModule.toString() );
             }
             catch ( final IOException e )
             {
                 throw new MavenReportException( e.getMessage(), e );
             }
             configLocation = rulesFiles.getAbsolutePath();
         }
         ClassLoader currentClassLoader = Thread.currentThread().getContextClassLoader();
 
         try
         {
             CheckstyleExecutorRequest request = createRequest().setLicenseArtifacts( collectArtifacts( "license" ) )
                             .setConfigurationArtifacts( collectArtifacts( "configuration" ) )
                             .setOmitIgnoredModules( omitIgnoredModules );
 
             CheckstyleResults results = checkstyleExecutor.executeCheckstyle( request );
 
             ResourceBundle bundle = getBundle( locale );
             generateReportStatics();
             generateMainReport( results, bundle );
             if ( enableRSS )
             {
                 CheckstyleRssGeneratorRequest checkstyleRssGeneratorRequest =
                     new CheckstyleRssGeneratorRequest( this.project, this.getCopyright(), outputDirectory, getLog() );
                 checkstyleRssGenerator.generateRSS( results, checkstyleRssGeneratorRequest );
             }
 
         }
         catch ( CheckstyleException e )
         {
             throw new MavenReportException( "Failed during checkstyle configuration", e );
         }
         catch ( CheckstyleExecutorException e )
         {
             throw new MavenReportException( "Failed during checkstyle execution", e );
         }
         finally
         {
             //be sure to restore original context classloader
             Thread.currentThread().setContextClassLoader( currentClassLoader );
         }
     }
 
     private void checkDeprecatedParameterUsage( Object parameter, String name, String replacement )
         throws MavenReportException
     {
         if ( parameter != null )
         {
             throw new MavenReportException( "You are using '" + name + "' which has been removed"
                 + " from the maven-checkstyle-plugin. " + "Please use '" + replacement
                 + "' and refer to the >>Major Version Upgrade to version 3.0.0<< " + "on the plugin site." );
         }
     }
 
     /**
      * Create the Checkstyle executor request.
      *
      * @return The executor request.
      * @throws MavenReportException If something goes wrong during creation.
      */
     protected abstract CheckstyleExecutorRequest createRequest()
             throws MavenReportException;
 
     private List<Artifact> collectArtifacts( String hint )
     {
         List<Artifact> artifacts = new ArrayList<>();
 
         PluginManagement pluginManagement = project.getBuild().getPluginManagement();
         if ( pluginManagement != null )
         {
             artifacts.addAll( getCheckstylePluginDependenciesAsArtifacts( pluginManagement.getPluginsAsMap(), hint ) );
         }
 
         artifacts.addAll( getCheckstylePluginDependenciesAsArtifacts( project.getBuild().getPluginsAsMap(), hint ) );
 
         return artifacts;
     }
 
     private List<Artifact> getCheckstylePluginDependenciesAsArtifacts( Map<String, Plugin> plugins, String hint )
     {
         List<Artifact> artifacts = new ArrayList<>();
 
         Plugin checkstylePlugin = plugins.get( plugin.getGroupId() + ":" + plugin.getArtifactId() );
         if ( checkstylePlugin != null )
         {
             for ( Dependency dep : checkstylePlugin.getDependencies() )
             {
              // @todo if we can filter on hints, it should be done here...
                 String depKey = dep.getGroupId() + ":" + dep.getArtifactId();
                 artifacts.add( plugin.getArtifactMap().get( depKey ) );
             }
         }
         return artifacts;
     }
 
     /**
      * Creates and returns the report generation listener.
      *
      * @return The audit listener.
      * @throws MavenReportException If something goes wrong.
      */
     protected AuditListener getListener()
         throws MavenReportException
     {
         AuditListener listener = null;
 
         if ( StringUtils.isNotEmpty( outputFileFormat ) )
         {
             File resultFile = outputFile;
 
             OutputStream out = getOutputStream( resultFile );
 
             if ( "xml".equals( outputFileFormat ) )
             {
                 listener = new XMLLogger( out, OutputStreamOptions.CLOSE );
             }
             else if ( "plain".equals( outputFileFormat ) )
             {
                 listener = new DefaultLogger( out, OutputStreamOptions.CLOSE );
             }
             else
             {
                 // TODO: failure if not a report
                 throw new MavenReportException( "Invalid output file format: (" + outputFileFormat
                     + "). Must be 'plain' or 'xml'." );
             }
         }
 
         return listener;
     }
 
     private OutputStream getOutputStream( File file )
         throws MavenReportException
     {
         File parentFile = file.getAbsoluteFile().getParentFile();
 
         if ( !parentFile.exists() )
         {
             parentFile.mkdirs();
         }
 
         FileOutputStream fileOutputStream;
         try
         {
             fileOutputStream = new FileOutputStream( file );
         }
         catch ( FileNotFoundException e )
         {
             throw new MavenReportException( "Unable to create output stream: " + file, e );
         }
         return fileOutputStream;
     }
 
     /**
      * Creates and returns the console listener.
      *
      * @return The console listener.
      * @throws MavenReportException If something goes wrong.
      */
     protected DefaultLogger getConsoleListener()
         throws MavenReportException
     {
         DefaultLogger consoleListener;
 
         if ( useFile == null )
         {
             stringOutputStream = new ByteArrayOutputStream();
             consoleListener = new DefaultLogger( stringOutputStream, OutputStreamOptions.NONE );
         }
         else
         {
             OutputStream out = getOutputStream( useFile );
 
             consoleListener = new DefaultLogger( out, OutputStreamOptions.CLOSE );
         }
 
         return consoleListener;
     }
 
     private void generateReportStatics()
         throws MavenReportException
     {
         ReportResource rresource = new ReportResource( PLUGIN_RESOURCES, outputDirectory );
         try
         {
             rresource.copy( "images/rss.png" );
         }
         catch ( IOException e )
         {
             throw new MavenReportException( "Unable to copy static resources.", e );
         }
     }
 
 
     private String getCopyright()
     {
         String copyright;
         int currentYear = Calendar.getInstance().get( Calendar.YEAR );
         if ( StringUtils.isNotEmpty( project.getInceptionYear() )
             && !String.valueOf( currentYear ).equals( project.getInceptionYear() ) )
         {
             copyright = project.getInceptionYear() + " - " + currentYear;
         }
         else
         {
             copyright = String.valueOf( currentYear );
         }
 
         if ( ( project.getOrganization() != null ) && StringUtils.isNotEmpty( project.getOrganization().getName() ) )
         {
             copyright = copyright + " " + project.getOrganization().getName();
         }
         return copyright;
     }
 
     private void generateMainReport( CheckstyleResults results, ResourceBundle bundle )
     {
         CheckstyleReportGenerator generator =
             new CheckstyleReportGenerator( getSink(), bundle, project.getBasedir(), siteTool, configLocation );
 
         generator.setLog( getLog() );
         generator.setEnableRulesSummary( enableRulesSummary );
         generator.setEnableSeveritySummary( enableSeveritySummary );
         generator.setEnableFilesSummary( enableFilesSummary );
         generator.setEnableRSS( enableRSS );
         generator.setCheckstyleConfig( results.getConfiguration() );
         if ( linkXRef )
         {
             initializeXrefLocation( generator );
             if ( generator.getXrefLocation() == null && results.getFileCount() > 0 )
             {
                 getLog().warn( "Unable to locate Source XRef to link to - DISABLED" );
             }
 
             initializeXrefTestLocation( generator );
             if ( generator.getXrefTestLocation() == null && results.getFileCount() > 0 )
             {
                 getLog().warn( "Unable to locate Test Source XRef to link to - DISABLED" );
             }
 
             generator.setTestSourceDirectories( getTestSourceDirectories() );
         }
         if ( treeWalkerNames != null )
         {
             generator.setTreeWalkerNames( treeWalkerNames );
         }
         generator.generateReport( results );
     }
 
     private void initializeXrefLocation( CheckstyleReportGenerator generator )
     {
       String relativePath = determineRelativePath( xrefLocation );
       if ( xrefLocation.exists() || checkMavenJxrPluginIsConfigured() )
       {
           // XRef was already generated by manual execution of a lifecycle binding
           // the report is on its way
           generator.setXrefLocation( relativePath );
       }
     }
 
     private void initializeXrefTestLocation( CheckstyleReportGenerator generator )
     {
       String relativePath = determineRelativePath( xrefTestLocation );
       if ( xrefTestLocation.exists() || checkMavenJxrPluginIsConfigured() )
       {
           // XRef was already generated by manual execution of a lifecycle binding
           // the report is on its way
           generator.setXrefTestLocation( relativePath );
       }
     }
 
     private String determineRelativePath( File location )
     {
       String relativePath = PathTool.getRelativePath( getOutputDirectory(), location.getAbsolutePath() );
       if ( relativePath == null || relativePath.trim().isEmpty() )
       {
           relativePath = ".";
       }
 
       return relativePath + "/" + location.getName();
     }
 
     private boolean checkMavenJxrPluginIsConfigured()
     {
         for ( ReportPlugin report : (Iterable<ReportPlugin>) getProject().getReportPlugins() )
         {
             String artifactId = report.getArtifactId();
             if ( "maven-jxr-plugin".equals( artifactId ) || "jxr-maven-plugin".equals( artifactId ) )
             {
                 return true;
             }
         }
 
         return false;
     }
 
     private static ResourceBundle getBundle( Locale locale )
     {
         return ResourceBundle.getBundle( "checkstyle-report", locale, AbstractCheckstyleReport.class.getClassLoader() );
     }
 
     protected List<File> getSourceDirectories()
     {
         if ( sourceDirectories == null )
         {
             sourceDirectories = project.getCompileSourceRoots();
         }
         List<File> sourceDirs = new ArrayList<>( sourceDirectories.size() );
         for ( String sourceDir : sourceDirectories )
         {
             sourceDirs.add( FileUtils.resolveFile( project.getBasedir(), sourceDir ) );
         }
         return sourceDirs;
     }
 
     protected List<File> getTestSourceDirectories()
     {
         if ( testSourceDirectories == null )
         {
             testSourceDirectories = project.getTestCompileSourceRoots();
         }
         List<File> testSourceDirs = new ArrayList<>( testSourceDirectories.size() );
         for ( String testSourceDir : testSourceDirectories )
         {
             testSourceDirs.add( FileUtils.resolveFile( project.getBasedir(), testSourceDir ) );
         }
         return testSourceDirs;
     }
 }