package org.apache.maven.plugin;

 /*

  * 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 static org.apache.maven.container.ContainerUtils.findChildComponentHints;

 import org.apache.maven.MavenArtifactFilterManager;

 import org.apache.maven.artifact.Artifact;

 import org.apache.maven.artifact.factory.ArtifactFactory;

 import org.apache.maven.artifact.metadata.ArtifactMetadataRetrievalException;

 import org.apache.maven.artifact.metadata.ArtifactMetadataSource;

 import org.apache.maven.artifact.metadata.ResolutionGroup;

 import org.apache.maven.artifact.repository.ArtifactRepository;

 import org.apache.maven.artifact.resolver.ArtifactNotFoundException;

 import org.apache.maven.artifact.resolver.ArtifactResolutionException;

 import org.apache.maven.artifact.resolver.ArtifactResolutionResult;

 import org.apache.maven.artifact.resolver.ArtifactResolver;

 import org.apache.maven.artifact.resolver.MultipleArtifactsNotFoundException;

 import org.apache.maven.artifact.resolver.filter.ArtifactFilter;

 import org.apache.maven.artifact.resolver.filter.ScopeArtifactFilter;

 import org.apache.maven.artifact.versioning.DefaultArtifactVersion;

 import org.apache.maven.artifact.versioning.InvalidVersionSpecificationException;

 import org.apache.maven.artifact.versioning.VersionRange;

 import org.apache.maven.execution.MavenSession;

 import org.apache.maven.execution.RuntimeInformation;

 import org.apache.maven.model.Plugin;

 import org.apache.maven.model.ReportPlugin;

 import org.apache.maven.monitor.event.EventDispatcher;

 import org.apache.maven.monitor.event.MavenEvents;

 import org.apache.maven.monitor.logging.DefaultLog;

 import org.apache.maven.plugin.descriptor.MojoDescriptor;

 import org.apache.maven.plugin.descriptor.Parameter;

 import org.apache.maven.plugin.descriptor.PluginDescriptor;

 import org.apache.maven.plugin.descriptor.PluginDescriptorBuilder;

 import org.apache.maven.plugin.logging.Log;

 import org.apache.maven.plugin.version.PluginVersionManager;

 import org.apache.maven.plugin.version.PluginVersionNotFoundException;

 import org.apache.maven.plugin.version.PluginVersionResolutionException;

 import org.apache.maven.project.MavenProject;

 import org.apache.maven.project.MavenProjectBuilder;

 import org.apache.maven.project.ProjectBuildingException;

 import org.apache.maven.project.artifact.InvalidDependencyVersionException;

 import org.apache.maven.project.artifact.MavenMetadataSource;

 import org.apache.maven.project.path.PathTranslator;

 import org.apache.maven.reporting.MavenReport;

 import org.apache.maven.settings.Settings;

 import org.apache.maven.wagon.Wagon;

 import org.codehaus.classworlds.ClassRealm;

 import org.codehaus.classworlds.NoSuchRealmException;

 import org.codehaus.plexus.PlexusConstants;

 import org.codehaus.plexus.PlexusContainer;

 import org.codehaus.plexus.PlexusContainerException;

 import org.codehaus.plexus.component.configurator.ComponentConfigurationException;

 import org.codehaus.plexus.component.configurator.ComponentConfigurator;

 import org.codehaus.plexus.component.configurator.ConfigurationListener;

 import org.codehaus.plexus.component.configurator.expression.ExpressionEvaluationException;

 import org.codehaus.plexus.component.configurator.expression.ExpressionEvaluator;

 import org.codehaus.plexus.component.discovery.ComponentDiscoveryListener;

 import org.codehaus.plexus.component.repository.ComponentDescriptor;

 import org.codehaus.plexus.component.repository.exception.ComponentLifecycleException;

 import org.codehaus.plexus.component.repository.exception.ComponentLookupException;

 import org.codehaus.plexus.configuration.PlexusConfiguration;

 import org.codehaus.plexus.configuration.xml.XmlPlexusConfiguration;

 import org.codehaus.plexus.context.Context;

 import org.codehaus.plexus.context.ContextException;

 import org.codehaus.plexus.logging.AbstractLogEnabled;

 import org.codehaus.plexus.personality.plexus.lifecycle.phase.Contextualizable;

 import org.codehaus.plexus.personality.plexus.lifecycle.phase.Initializable;

 import org.codehaus.plexus.util.StringUtils;

 import org.codehaus.plexus.util.xml.Xpp3Dom;

 import java.io.File;

 import java.net.URL;

 import java.util.ArrayList;

 import java.util.Arrays;

 import java.util.Collection;

 import java.util.Collections;

 import java.util.HashMap;

 import java.util.HashSet;

 import java.util.Iterator;

 import java.util.LinkedHashMap;

 import java.util.LinkedHashSet;

 import java.util.List;

 import java.util.Map;

 import java.util.Set;

 public class DefaultPluginManager

     extends AbstractLogEnabled

     implements PluginManager, Initializable, Contextualizable

 {

     protected PlexusContainer container;

     protected PluginDescriptorBuilder pluginDescriptorBuilder;

     protected ArtifactFilter artifactFilter;

     private Log mojoLogger;

     private Map resolvedCoreArtifactFiles = new HashMap();

     // component requirements

     protected PathTranslator pathTranslator;

     protected MavenPluginCollector pluginCollector;

     protected PluginVersionManager pluginVersionManager;

     protected ArtifactFactory artifactFactory;

     protected ArtifactResolver artifactResolver;

     protected ArtifactMetadataSource artifactMetadataSource;

     protected RuntimeInformation runtimeInformation;

     protected MavenProjectBuilder mavenProjectBuilder;

     protected PluginMappingManager pluginMappingManager;

     // END component requirements

     public DefaultPluginManager()

     {

         pluginDescriptorBuilder = new PluginDescriptorBuilder();

     }

     // ----------------------------------------------------------------------

     //

     // ----------------------------------------------------------------------

     public PluginDescriptor getPluginDescriptorForPrefix( String prefix )

     {

         return pluginCollector.getPluginDescriptorForPrefix( prefix );

     }

     public Plugin getPluginDefinitionForPrefix( String prefix,

                                                 MavenSession session,

                                                 MavenProject project )

     {

         // TODO: since this is only used in the lifecycle executor, maybe it should be moved there? There is no other

         // use for the mapping manager in here

         return pluginMappingManager.getByPrefix( prefix, session.getSettings().getPluginGroups(),

                                                  project.getPluginArtifactRepositories(),

                                                  session.getLocalRepository() );

     }

     /**

      * {@inheritDoc}

      */

     public PluginDescriptor verifyPlugin( Plugin plugin,

                                           MavenProject project,

                                           Settings settings,

                                           ArtifactRepository localRepository )

         throws ArtifactResolutionException, PluginVersionResolutionException, ArtifactNotFoundException,

         InvalidVersionSpecificationException, InvalidPluginException, PluginManagerException, PluginNotFoundException,

         PluginVersionNotFoundException

     {

         // TODO: this should be possibly outside

         // All version-resolution logic has been moved to DefaultPluginVersionManager.

         if ( plugin.getVersion() == null )

         {

             String version = pluginVersionManager.resolvePluginVersion( plugin.getGroupId(), plugin.getArtifactId(),

                                                                         project, settings, localRepository );

             plugin.setVersion( version );

         }

         return verifyVersionedPlugin( plugin, project, localRepository );

     }

     private PluginDescriptor verifyVersionedPlugin( Plugin plugin,

                                                     MavenProject project,

                                                     ArtifactRepository localRepository )

         throws PluginVersionResolutionException, ArtifactNotFoundException, ArtifactResolutionException,

         InvalidVersionSpecificationException, InvalidPluginException, PluginManagerException, PluginNotFoundException

     {

         // TODO: this might result in an artifact "RELEASE" being resolved continuously

         // FIXME: need to find out how a plugin gets marked as 'installed'

         // and no ChildContainer exists. The check for that below fixes

         // the 'Can't find plexus container for plugin: xxx' error.

         try

         {

             VersionRange versionRange = VersionRange.createFromVersionSpec( plugin.getVersion() );

             List remoteRepositories = new ArrayList();

             remoteRepositories.addAll( project.getPluginArtifactRepositories() );

             remoteRepositories.addAll( project.getRemoteArtifactRepositories() );

             checkRequiredMavenVersion( plugin, localRepository, remoteRepositories );

             Artifact pluginArtifact =

                 artifactFactory.createPluginArtifact( plugin.getGroupId(), plugin.getArtifactId(), versionRange );

             pluginArtifact = project.replaceWithActiveArtifact( pluginArtifact );

             artifactResolver.resolve( pluginArtifact, project.getPluginArtifactRepositories(), localRepository );

             plugin.setVersion( pluginArtifact.getBaseVersion() );

             String pluginKey = PluginUtils.constructVersionedKey( plugin );

             PlexusContainer pluginContainer = container.getChildContainer( pluginKey );

             File pluginFile = pluginArtifact.getFile();

             if ( !pluginCollector.isPluginInstalled( plugin ) || ( pluginContainer == null ) )

             {

                 addPlugin( plugin, pluginArtifact, project, localRepository );

             }

             else if ( pluginFile.lastModified() > pluginContainer.getCreationDate().getTime() )

             {

                 getLogger().info(

                     "Reloading plugin container for: " + pluginKey + ". The plugin artifact has changed." );

                 pluginContainer.dispose();

                 pluginCollector.flushPluginDescriptor( plugin );

                 addPlugin( plugin, pluginArtifact, project, localRepository );

             }

             project.addPlugin( plugin );

         }

         catch ( ArtifactNotFoundException e )

         {

             String groupId = plugin.getGroupId();

             String artifactId = plugin.getArtifactId();

             String version = plugin.getVersion();

             if ( ( groupId == null ) || ( artifactId == null ) || ( version == null ) )

             {

                 throw new PluginNotFoundException( e );

             }

             else if ( groupId.equals( e.getGroupId() ) && artifactId.equals( e.getArtifactId() ) &&

                 version.equals( e.getVersion() ) && "maven-plugin".equals( e.getType() ) )

             {

                 throw new PluginNotFoundException( e );

             }

             else

             {

                 throw e;

             }

         }

         return pluginCollector.getPluginDescriptor( plugin );

     }

     /**

      * @todo would be better to store this in the plugin descriptor, but then it won't be available to the version

      * manager which executes before the plugin is instantiated

      */

     private void checkRequiredMavenVersion( Plugin plugin,

                                             ArtifactRepository localRepository,

                                             List remoteRepositories )

         throws PluginVersionResolutionException, InvalidPluginException

     {

         try

         {

             Artifact artifact = artifactFactory.createProjectArtifact( plugin.getGroupId(), plugin.getArtifactId(),

                                                                        plugin.getVersion() );

             MavenProject project =

                 mavenProjectBuilder.buildFromRepository( artifact, remoteRepositories, localRepository, false );

             // if we don't have the required Maven version, then ignore an update

             if ( ( project.getPrerequisites() != null ) && ( project.getPrerequisites().getMaven() != null ) )

             {

                 DefaultArtifactVersion requiredVersion =

                     new DefaultArtifactVersion( project.getPrerequisites().getMaven() );

                 if ( runtimeInformation.getApplicationVersion().compareTo( requiredVersion ) < 0 )

                 {

                     throw new PluginVersionResolutionException( plugin.getGroupId(), plugin.getArtifactId(),

                                                                 "Plugin requires Maven version " + requiredVersion );

                 }

             }

         }

         catch ( ProjectBuildingException e )

         {

             throw new InvalidPluginException(

                 "Unable to build project for plugin '" + plugin.getKey() + "': " + e.getMessage(), e );

         }

     }

     protected void addPlugin( Plugin plugin,

                               Artifact pluginArtifact,

                               MavenProject project,

                               ArtifactRepository localRepository )

         throws PluginManagerException, InvalidPluginException

     {

         PlexusContainer child;

         try

         {

             MavenPluginValidator validator = new MavenPluginValidator( pluginArtifact );

             String key = PluginUtils.constructVersionedKey( plugin ).intern();

             child = container.createChildContainer( key,

                                                     Collections.singletonList( pluginArtifact.getFile() ),

                                                     Collections.EMPTY_MAP,

                                                     Arrays.asList( new ComponentDiscoveryListener[] { validator, pluginCollector } ) );

             // remove listeners for efficiency since they are only needed for the initial stage and

             // should not be applied to the plugin's dependencies

             child.removeComponentDiscoveryListener( validator );

             child.removeComponentDiscoveryListener( pluginCollector );

             if ( validator.hasErrors() )

             {

                 String msg = "Plugin '" + key + "' has an invalid descriptor:";

                 int count = 1;

                 for ( Iterator i = validator.getErrors().iterator(); i.hasNext(); )

                 {

                     msg += "\n" + count + ") " + i.next();

                     count++;

                 }

                 throw new PluginManagerException( msg );

             }

             try

             {

                 child.getContainerRealm().importFrom( "plexus.core", "org.codehaus.plexus.util.xml.Xpp3Dom" );

                 child.getContainerRealm().importFrom( "plexus.core", "org.codehaus.plexus.util.xml.pull.XmlPullParser" );

                 child.getContainerRealm().importFrom( "plexus.core", "org.codehaus.plexus.util.xml.pull.XmlPullParserException" );

                 child.getContainerRealm().importFrom( "plexus.core", "org.codehaus.plexus.util.xml.pull.XmlSerializer" );

                 // MNG-2878

                 child.getContainerRealm().importFrom( "plexus.core", "/default-report.xml" );

             }

             catch ( NoSuchRealmException e )

             {

                 // won't happen

             }

         }

         catch ( PlexusContainerException e )

         {

             throw new PluginManagerException(

                 "Failed to create plugin container for plugin '" + plugin + "': " + e.getMessage(), e );

         }

         // this plugin's descriptor should have been discovered in the child creation, so we should be able to

         // circle around and set the artifacts and class realm

         PluginDescriptor addedPlugin = pluginCollector.getPluginDescriptor( plugin );

         if ( addedPlugin == null )

         {

             throw new IllegalStateException( "The plugin descriptor for the plugin " + plugin + " was not found."

                 + " Please verify that the plugin JAR " + pluginArtifact.getFile() + " is intact." );

         }

         addedPlugin.setClassRealm( child.getContainerRealm() );

         // we're only setting the plugin's artifact itself as the artifact list, to allow it to be retrieved

         // later when the plugin is first invoked. Retrieving this artifact will in turn allow us to

         // transitively resolve its dependencies, and add them to the plugin container...

         addedPlugin.setArtifacts( Collections.singletonList( pluginArtifact ) );

         addedPlugin.setPluginArtifact( pluginArtifact );

         try

         {

             // the only Plugin instance which will have dependencies is the one specified in the project.

             // We need to look for a Plugin instance there, in case the instance we're using didn't come from

             // the project.

             Plugin projectPlugin = (Plugin) project.getBuild().getPluginsAsMap().get( plugin.getKey() );

             if ( projectPlugin == null )

             {

                 projectPlugin = plugin;

             }

             Set artifacts = MavenMetadataSource.createArtifacts( artifactFactory, projectPlugin.getDependencies(), null,

                                                                  null, project );

 //            Set artifacts =

 //                MavenMetadataSource.createArtifacts( artifactFactory, plugin.getDependencies(), null, null, project );

             addedPlugin.setIntroducedDependencyArtifacts( artifacts );

         }

         catch ( InvalidDependencyVersionException e )

         {

             throw new InvalidPluginException( "Plugin '" + plugin + "' is invalid: " + e.getMessage(), e );

         }

     }

     // ----------------------------------------------------------------------

     // Mojo execution

     // ----------------------------------------------------------------------

     public void executeMojo( MavenProject project,

                              MojoExecution mojoExecution,

                              MavenSession session )

         throws ArtifactResolutionException, MojoExecutionException, MojoFailureException, ArtifactNotFoundException,

         InvalidDependencyVersionException, PluginManagerException, PluginConfigurationException

     {

         MojoDescriptor mojoDescriptor = mojoExecution.getMojoDescriptor();

         // NOTE: I'm putting these checks in here, since this is the central point of access for

         // anything that wants to execute a mojo.

         if ( mojoDescriptor.isProjectRequired() && !session.isUsingPOMsFromFilesystem() )

         {

             throw new MojoExecutionException( "Cannot execute mojo: " + mojoDescriptor.getGoal() +

                 ". It requires a project with an existing pom.xml, but the build is not using one." );

         }

         if ( mojoDescriptor.isOnlineRequired() && session.getSettings().isOffline() )

         {

             // TODO: Should we error out, or simply warn and skip??

             throw new MojoExecutionException( "Mojo: " + mojoDescriptor.getGoal() +

                 " requires online mode for execution. Maven is currently offline." );

         }

         if ( mojoDescriptor.isDependencyResolutionRequired() != null )

         {

             Collection projects;

             if ( mojoDescriptor.isAggregator() )

             {

                 projects = session.getSortedProjects();

             }

             else

             {

                 projects = Collections.singleton( project );

             }

             for ( Iterator i = projects.iterator(); i.hasNext(); )

             {

                 MavenProject p = (MavenProject) i.next();

                 resolveTransitiveDependencies( session, artifactResolver,

                                                mojoDescriptor.isDependencyResolutionRequired(), artifactFactory, p, mojoDescriptor.isAggregator() );

             }

             downloadDependencies( project, session, artifactResolver );

         }

         String goalName = mojoDescriptor.getFullGoalName();

         Mojo plugin;

         PluginDescriptor pluginDescriptor = mojoDescriptor.getPluginDescriptor();

         String goalId = mojoDescriptor.getGoal();

         String groupId = pluginDescriptor.getGroupId();

         String artifactId = pluginDescriptor.getArtifactId();

         String executionId = mojoExecution.getExecutionId();

         Xpp3Dom dom = project.getGoalConfiguration( groupId, artifactId, executionId, goalId );

         Xpp3Dom reportDom = project.getReportConfiguration( groupId, artifactId, executionId );

         dom = Xpp3Dom.mergeXpp3Dom( dom, reportDom );

         if ( mojoExecution.getConfiguration() != null )

         {

             dom = Xpp3Dom.mergeXpp3Dom( dom, mojoExecution.getConfiguration() );

         }

         plugin = getConfiguredMojo( session, dom, project, false, mojoExecution );

         // Event monitoring.

         String event = MavenEvents.MOJO_EXECUTION;

         EventDispatcher dispatcher = session.getEventDispatcher();

         String goalExecId = goalName;

         if ( mojoExecution.getExecutionId() != null )

         {

             goalExecId += " {execution: " + mojoExecution.getExecutionId() + "}";

         }

         dispatcher.dispatchStart( event, goalExecId );

         ClassLoader oldClassLoader = Thread.currentThread().getContextClassLoader();

         try

         {

             Thread.currentThread().setContextClassLoader(

                 mojoDescriptor.getPluginDescriptor().getClassRealm().getClassLoader() );

             plugin.execute();

             dispatcher.dispatchEnd( event, goalExecId );

         }

         catch ( MojoExecutionException e )

         {

             session.getEventDispatcher().dispatchError( event, goalExecId, e );

             throw e;

         }

         catch ( MojoFailureException e )

         {

             session.getEventDispatcher().dispatchError( event, goalExecId, e );

             throw e;

         }

         catch ( LinkageError e )

         {

             if ( getLogger().isFatalErrorEnabled() )

             {

                 getLogger().fatalError(

                                         plugin.getClass().getName() + "#execute() caused a linkage error ("

                                             + e.getClass().getName() + ") and may be out-of-date. Check the realms:" );

                 ClassRealm pluginRealm = mojoDescriptor.getPluginDescriptor().getClassRealm();

                 StringBuffer sb = new StringBuffer();

                 sb.append( "Plugin realm = " + pluginRealm.getId() ).append( '\n' );

                 for ( int i = 0; i < pluginRealm.getConstituents().length; i++ )

                 {

                     sb.append( "urls[" + i + "] = " + pluginRealm.getConstituents()[i] );

                     if ( i != ( pluginRealm.getConstituents().length - 1 ) )

                     {

                         sb.append( '\n' );

                     }

                 }

                 getLogger().fatalError( sb.toString() );

                 ClassRealm containerRealm = container.getContainerRealm();

                 sb = new StringBuffer();

                 sb.append( "Container realm = " + containerRealm.getId() ).append( '\n' );

                 for ( int i = 0; i < containerRealm.getConstituents().length; i++ )

                 {

                     sb.append( "urls[" + i + "] = " + containerRealm.getConstituents()[i] );

                     if ( i != ( containerRealm.getConstituents().length - 1 ) )

                     {

                         sb.append( '\n' );

                     }

                 }

                 getLogger().fatalError( sb.toString() );

             }

             session.getEventDispatcher().dispatchError( event, goalExecId, e );

             throw e;

         }

         finally

         {

             Thread.currentThread().setContextClassLoader( oldClassLoader );

             try

             {

                 PlexusContainer pluginContainer = getPluginContainer( mojoDescriptor.getPluginDescriptor() );

                 pluginContainer.release( plugin );

             }

             catch ( ComponentLifecycleException e )

             {

                 if ( getLogger().isErrorEnabled() )

                 {

                     getLogger().error( "Error releasing plugin - ignoring.", e );

                 }

             }

         }

     }

     public MavenReport getReport( MavenProject project,

                                   MojoExecution mojoExecution,

                                   MavenSession session )

         throws ArtifactNotFoundException, PluginConfigurationException, PluginManagerException,

         ArtifactResolutionException

     {

         MojoDescriptor mojoDescriptor = mojoExecution.getMojoDescriptor();

         PluginDescriptor descriptor = mojoDescriptor.getPluginDescriptor();

         Xpp3Dom dom = project.getReportConfiguration( descriptor.getGroupId(), descriptor.getArtifactId(),

                                                       mojoExecution.getExecutionId() );

         if ( mojoExecution.getConfiguration() != null )

         {

             dom = Xpp3Dom.mergeXpp3Dom( dom, mojoExecution.getConfiguration() );

         }

         MavenReport report = (MavenReport) getConfiguredMojo( session, dom, project, true, mojoExecution );

         return report;

     }

     public PluginDescriptor verifyReportPlugin( ReportPlugin reportPlugin,

                                                 MavenProject project,

                                                 MavenSession session )

         throws PluginVersionResolutionException, ArtifactResolutionException, ArtifactNotFoundException,

         InvalidVersionSpecificationException, InvalidPluginException, PluginManagerException, PluginNotFoundException,

         PluginVersionNotFoundException

     {

         String version = reportPlugin.getVersion();

         if ( version == null )

         {

             version = pluginVersionManager.resolveReportPluginVersion( reportPlugin.getGroupId(),

                                                                        reportPlugin.getArtifactId(), project,

                                                                        session.getSettings(),

                                                                        session.getLocalRepository() );

             reportPlugin.setVersion( version );

         }

         Plugin forLookup = new Plugin();

         forLookup.setGroupId( reportPlugin.getGroupId() );

         forLookup.setArtifactId( reportPlugin.getArtifactId() );

         forLookup.setVersion( version );

         return verifyVersionedPlugin( forLookup, project, session.getLocalRepository() );

     }

     private PlexusContainer getPluginContainer( PluginDescriptor pluginDescriptor )

         throws PluginManagerException

     {

         String pluginKey = PluginUtils.constructVersionedKey( pluginDescriptor );

         PlexusContainer pluginContainer = container.getChildContainer( pluginKey );

         if ( pluginContainer == null )

         {

             throw new PluginManagerException( "Cannot find Plexus container for plugin: " + pluginKey );

         }

         return pluginContainer;

     }

     private Mojo getConfiguredMojo( MavenSession session,

                                     Xpp3Dom dom,

                                     MavenProject project,

                                     boolean report,

                                     MojoExecution mojoExecution )

         throws PluginConfigurationException, ArtifactNotFoundException, PluginManagerException,

         ArtifactResolutionException

     {

         MojoDescriptor mojoDescriptor = mojoExecution.getMojoDescriptor();

         PluginDescriptor pluginDescriptor = mojoDescriptor.getPluginDescriptor();

         PlexusContainer pluginContainer = getPluginContainer( pluginDescriptor );

         // if this is the first time this plugin has been used, the plugin's container will only

         // contain the plugin's artifact in isolation; we need to finish resolving the plugin's

         // dependencies, and add them to the container.

         ensurePluginContainerIsComplete( pluginDescriptor, pluginContainer, project, session );

         Mojo plugin;

         try

         {

             plugin = (Mojo) pluginContainer.lookup( Mojo.ROLE, mojoDescriptor.getRoleHint() );

             if ( report && !( plugin instanceof MavenReport ) )

             {

                 // TODO: the mojoDescriptor should actually capture this information so we don't get this far

                 return null;

             }

         }

         catch ( ComponentLookupException e )

         {

             Throwable cause = e.getCause();

             while( cause != null && !(cause instanceof NoClassDefFoundError ) )

             {

                 cause = cause.getCause();

             }

             if ( cause != null && ( cause instanceof NoClassDefFoundError ) )

             {

                 throw new PluginManagerException( "Unable to load the mojo '" + mojoDescriptor.getRoleHint()

                                                   + "' in the plugin '" + pluginDescriptor.getPluginLookupKey() + "'. A required class is missing: "

                                                   + cause.getMessage(), e );

             }

             throw new PluginManagerException( "Unable to find the mojo '" + mojoDescriptor.getGoal() +

                 "' (or one of its required components) in the plugin '" + pluginDescriptor.getPluginLookupKey() + "'", e );

         }

         catch ( NoClassDefFoundError e )

         {

             throw new PluginManagerException( "Unable to load the mojo '" + mojoDescriptor.getRoleHint()

                 + "' in the plugin '" + pluginDescriptor.getPluginLookupKey() + "'. A required class is missing: "

                 + e.getMessage(), e );

         }

         if ( plugin instanceof ContextEnabled )

         {

             Map pluginContext = session.getPluginContext( pluginDescriptor, project );

             ( (ContextEnabled) plugin ).setPluginContext( pluginContext );

         }

         plugin.setLog( mojoLogger );

         XmlPlexusConfiguration pomConfiguration;

         if ( dom == null )

         {

             pomConfiguration = new XmlPlexusConfiguration( "configuration" );

         }

         else

         {

             pomConfiguration = new XmlPlexusConfiguration( dom );

         }

         // Validate against non-editable (@readonly) parameters, to make sure users aren't trying to

         // override in the POM.

         validatePomConfiguration( mojoDescriptor, pomConfiguration );

         PlexusConfiguration mergedConfiguration = mergeMojoConfiguration( pomConfiguration, mojoDescriptor );

         // TODO: plexus changes to make this more like the component descriptor so this can be used instead

         //            PlexusConfiguration mergedConfiguration = mergeConfiguration( pomConfiguration,

         //                                                                          mojoDescriptor.getConfiguration() );

         ExpressionEvaluator expressionEvaluator = new PluginParameterExpressionEvaluator( session, mojoExecution,

                                                                                           pathTranslator,

                                                                                           getLogger(),

                                                                                           project,

                                                                                           session.getExecutionProperties() );

         PlexusConfiguration extractedMojoConfiguration =

             extractMojoConfiguration( mergedConfiguration, mojoDescriptor );

         checkRequiredParameters( mojoDescriptor, extractedMojoConfiguration, expressionEvaluator );

         populatePluginFields( plugin, mojoDescriptor, extractedMojoConfiguration, pluginContainer,

                               expressionEvaluator );

         return plugin;

     }

     private void ensurePluginContainerIsComplete( PluginDescriptor pluginDescriptor,

                                                   PlexusContainer pluginContainer,

                                                   MavenProject project,

                                                   MavenSession session )

         throws ArtifactNotFoundException, PluginManagerException, ArtifactResolutionException

     {

         // if the plugin's already been used once, don't re-do this step...

         // otherwise, we have to finish resolving the plugin's classpath and start the container.

         if ( ( pluginDescriptor.getArtifacts() != null ) && ( pluginDescriptor.getArtifacts().size() == 1 ) )

         {

             Artifact pluginArtifact = (Artifact) pluginDescriptor.getArtifacts().get( 0 );

             ArtifactRepository localRepository = session.getLocalRepository();

             ResolutionGroup resolutionGroup;

             try

             {

                 resolutionGroup = artifactMetadataSource.retrieve( pluginArtifact, localRepository,

                                                                    project.getPluginArtifactRepositories() );

             }

             catch ( ArtifactMetadataRetrievalException e )

             {

                 throw new ArtifactResolutionException( "Unable to download metadata from repository for plugin '" +

                     pluginArtifact.getId() + "': " + e.getMessage(), pluginArtifact, e );

             }

             Set rgArtifacts = resolutionGroup.getArtifacts();

             rgArtifacts = checkPlexusUtils( rgArtifacts, artifactFactory );

             // [jdcasey; 20-March-2008]:

             // This is meant to eliminate the introduction of duplicated artifacts.

             // Since much of the reasoning for reversing the order of introduction of

             // plugin dependencies rests on the notion that we need to be able to

             // introduce upgraded versions of plugin dependencies on a case-by-case

             // basis, we need to remove the original version prior to artifact

             // resolution. This is consistent with recent thinking on duplicated

             // dependency specifications within a POM, where that case should

             // throw a model validation exception.

             //

             // Here, we just want to remove any chance that the ArtifactCollector

             // could make a bad choice, and use the old version in spite of our

             // explicit preference otherwise.

             // First, we're going to accumulate plugin dependencies in an ordered map,

             // keyed by dependencyConflictId (the ordered map is meant to preserve relative

             // ordering of the dependencies that do make the cut).

             Map dependencyMap = new LinkedHashMap();

             // Next, we need to accumulate all dependencies in a List, to make it

             // simpler to iterate through them all and add them to the map.

             List all = new ArrayList();

             // plugin-level dependencies from the consuming POM override dependencies

             // from the plugin's own POM.

             all.addAll( pluginDescriptor.getIntroducedDependencyArtifacts() );

             // add in the deps from the plugin POM now.

             all.addAll( rgArtifacts );

             for ( Iterator it = all.iterator(); it.hasNext(); )

             {

                 Artifact artifact = (Artifact) it.next();

                 String conflictId = artifact.getDependencyConflictId();

                 // if the map already contains this dependencyConflictId, it constitutes an

                 // overridden dependency. Don't use the old one (we know it's old from the

                 // order in which dependencies were added to this list).

                 if ( !dependencyMap.containsKey( conflictId ) )

                 {

                     dependencyMap.put( conflictId, artifact );

                 }

             }

             // Create an ordered set of dependencies from the ordered map we used above, to feed into the resolver.

             Set dependencies = new LinkedHashSet( dependencyMap.values() );

             if ( getLogger().isDebugEnabled() )

             {

                 // list all dependencies to be used by this plugin (first-level deps, not transitive ones).

                 getLogger().debug( "Plugin dependencies for:\n\n" + pluginDescriptor.getId()

                                    + "\n\nare:\n\n"

                                    + StringUtils.join( dependencies.iterator(), "\n" ) + "\n\n" );

             }

             List repositories = new ArrayList();

             repositories.addAll( resolutionGroup.getResolutionRepositories() );

             repositories.addAll( project.getRemoteArtifactRepositories() );

             /* get plugin managed versions */

             Map pluginManagedDependencies = new HashMap();

             try

             {

                 MavenProject pluginProject =

                     mavenProjectBuilder.buildFromRepository( pluginArtifact, project.getRemoteArtifactRepositories(),

                                                              localRepository );

                 if ( pluginProject != null )

                 {

                     pluginManagedDependencies = pluginProject.getManagedVersionMap();

                 }

             }

             catch ( ProjectBuildingException e )

             {

                 // this can't happen, it would have blowed up at artifactMetadataSource.retrieve()

             }

             ArtifactResolutionResult result = artifactResolver.resolveTransitively( dependencies, pluginArtifact,

                                                                                     pluginManagedDependencies,

                                                                                     localRepository, repositories,

                                                                                     artifactMetadataSource,

                                                                                     artifactFilter );

             Set resolved = result.getArtifacts();

             for ( Iterator it = resolved.iterator(); it.hasNext(); )

             {

                 Artifact artifact = (Artifact) it.next();

                 if ( !artifact.equals( pluginArtifact ) )

                 {

                     artifact = project.replaceWithActiveArtifact( artifact );

                     try

                     {

                         pluginContainer.addJarResource( artifact.getFile() );

                     }

                     catch ( PlexusContainerException e )

                     {

                         throw new PluginManagerException( "Error adding plugin dependency '" +

                             artifact.getDependencyConflictId() + "' into plugin manager: " + e.getMessage(), e );

                     }

                 }

             }

             pluginDescriptor.setClassRealm( pluginContainer.getContainerRealm() );

             List unresolved = new ArrayList( dependencies );

             unresolved.removeAll( resolved );

             if ( getLogger().isDebugEnabled() )

             {

                 // list all artifacts that were filtered out during the resolution process.

                 // these are already present in the core container.

                 getLogger().debug( " The following artifacts were filtered out for plugin: "

                                    + pluginDescriptor.getId()

                                    + " because they're already in the core of Maven:\n\n"

                                    + StringUtils.join( unresolved.iterator(), "\n" )

                                    + "\n\nThese will use the artifact files already in the core ClassRealm instead, to allow them to be included in PluginDescriptor.getArtifacts().\n\n" );

             }

             // Grab a file for all filtered artifacts, even if it means resolving them. This

             // is necessary in order to present a full complement of a plugin's transitive

             // dependencies to anyone who calls PluginDescriptor.getArtifacts().

             resolveCoreArtifacts( unresolved, localRepository, resolutionGroup.getResolutionRepositories() );

             // Re-join resolved and filtered-but-now-resolved artifacts.

             // NOTE: The process of filtering then re-adding some artifacts will

             // result in different ordering within the PluginDescriptor.getArtifacts()

             // List than should have happened if none had been filtered. All filtered

             // artifacts will be listed last...

             List allResolved = new ArrayList( resolved.size() + unresolved.size() );

             allResolved.addAll( resolved );

             allResolved.addAll( unresolved );

             pluginDescriptor.setArtifacts( allResolved );

         }

     }

     public static Set checkPlexusUtils( Set dependencyArtifacts, ArtifactFactory artifactFactory )

     {

         // ----------------------------------------------------------------------------

         // If the plugin already declares a dependency on plexus-utils then we're all

         // set as the plugin author is aware of its use. If we don't have a dependency

         // on plexus-utils then we must protect users from stupid plugin authors who

         // did not declare a direct dependency on plexus-utils because the version

         // Maven uses is hidden from downstream use. We will also bump up any

         // anything below 1.1 to 1.1 as this mimics the behaviour in 2.0.5 where

         // plexus-utils 1.1 was being forced into use.

         // ----------------------------------------------------------------------------

         VersionRange vr = null;

         try

         {

             vr = VersionRange.createFromVersionSpec( "[1.1,)" );

         }

         catch ( InvalidVersionSpecificationException e )

         {

             // Won't happen

         }

         boolean plexusUtilsPresent = false;

         for ( Iterator i = dependencyArtifacts.iterator(); i.hasNext(); )

         {

             Artifact a = (Artifact) i.next();

             if ( a.getArtifactId().equals( "plexus-utils" ) &&

                 vr.containsVersion( new DefaultArtifactVersion( a.getVersion() ) ) )

             {

                 plexusUtilsPresent = true;

                 break;

             }

         }

         if ( !plexusUtilsPresent )

         {

             // We will add plexus-utils as every plugin was getting this anyway from Maven itself. We will set the

             // version to the latest version we know that works as of the 2.0.6 release. We set the scope to runtime

             // as this is what's implicitly happening in 2.0.6.

             Set result = new LinkedHashSet();

             if ( !dependencyArtifacts.isEmpty() )

             {

                 result.addAll( dependencyArtifacts );

             }

             result.add( artifactFactory.createArtifact( "org.codehaus.plexus", "plexus-utils", "1.1", Artifact.SCOPE_RUNTIME, "jar" ) );

             return result;

         }

         else

         {

             return dependencyArtifacts;

         }

     }

     private void resolveCoreArtifacts( List unresolved,

                                        ArtifactRepository localRepository,

                                        List resolutionRepositories )

         throws ArtifactResolutionException, ArtifactNotFoundException

     {

         for ( Iterator it = unresolved.iterator(); it.hasNext(); )

         {

             Artifact artifact = (Artifact) it.next();

             File artifactFile = (File) resolvedCoreArtifactFiles.get( artifact.getId() );

             if ( artifactFile == null )

             {

                 String resource =

                     "/META-INF/maven/" + artifact.getGroupId() + "/" + artifact.getArtifactId() + "/pom.xml";

                 URL resourceUrl = container.getContainerRealm().getResource( resource );

                 if ( resourceUrl == null )

                 {

                     artifactResolver.resolve( artifact, resolutionRepositories, localRepository );

                     artifactFile = artifact.getFile();

                 }

                 else

                 {

                     String artifactPath = resourceUrl.getPath();

                     if ( artifactPath.startsWith( "file:" ) )

                     {

                         artifactPath = artifactPath.substring( "file:".length() );

                     }

                     artifactPath = artifactPath.substring( 0, artifactPath.length() - resource.length() );

                     if ( artifactPath.endsWith( "/" ) )

                     {

                         artifactPath = artifactPath.substring( 0, artifactPath.length() - 1 );

                     }

                     if ( artifactPath.endsWith( "!" ) )

                     {

                         artifactPath = artifactPath.substring( 0, artifactPath.length() - 1 );

                     }

                     artifactFile = new File( artifactPath ).getAbsoluteFile();

                 }

                 resolvedCoreArtifactFiles.put( artifact.getId(), artifactFile );

             }

             artifact.setFile( artifactFile );

         }

     }

     private PlexusConfiguration extractMojoConfiguration( PlexusConfiguration mergedConfiguration,

                                                           MojoDescriptor mojoDescriptor )

     {

         Map parameterMap = mojoDescriptor.getParameterMap();

         PlexusConfiguration[] mergedChildren = mergedConfiguration.getChildren();

         XmlPlexusConfiguration extractedConfiguration = new XmlPlexusConfiguration( "configuration" );

         for ( int i = 0; i < mergedChildren.length; i++ )

         {

             PlexusConfiguration child = mergedChildren[i];

             if ( parameterMap.containsKey( child.getName() ) )

             {

                 extractedConfiguration.addChild( copyConfiguration( child ) );

             }

             else

             {

                 // TODO: I defy anyone to find these messages in the '-X' output! Do we need a new log level?

                 // ideally, this would be elevated above the true debug output, but below the default INFO level...

                 // [BP] (2004-07-18): need to understand the context more but would prefer this could be either WARN or

                 // removed - shouldn't need DEBUG to diagnose a problem most of the time.

                 getLogger().debug( "*** WARNING: Configuration \'" + child.getName() + "\' is not used in goal \'" +

                     mojoDescriptor.getFullGoalName() + "; this may indicate a typo... ***" );

             }

         }

         return extractedConfiguration;

     }

     private void checkRequiredParameters( MojoDescriptor goal,

                                           PlexusConfiguration configuration,

                                           ExpressionEvaluator expressionEvaluator )

         throws PluginConfigurationException

     {

         // TODO: this should be built in to the configurator, as we presently double process the expressions

         List parameters = goal.getParameters();

         if ( parameters == null )

         {

             return;

         }

         List invalidParameters = new ArrayList();

         for ( int i = 0; i < parameters.size(); i++ )

         {

             Parameter parameter = (Parameter) parameters.get( i );

             if ( parameter.isRequired() )

             {

                 // the key for the configuration map we're building.

                 String key = parameter.getName();

                 Object fieldValue = null;

                 String expression = null;

                 PlexusConfiguration value = configuration.getChild( key, false );

                 try

                 {

                     if ( value != null )

                     {

                         expression = value.getValue( null );

                         fieldValue = expressionEvaluator.evaluate( expression );

                         if ( fieldValue == null )

                         {

                             fieldValue = value.getAttribute( "default-value", null );

                         }

                     }

                     if ( ( fieldValue == null ) && StringUtils.isNotEmpty( parameter.getAlias() ) )

                     {

                         value = configuration.getChild( parameter.getAlias(), false );

                         if ( value != null )

                         {

                             expression = value.getValue( null );

                             fieldValue = expressionEvaluator.evaluate( expression );

                             if ( fieldValue == null )

                             {

                                 fieldValue = value.getAttribute( "default-value", null );

                             }

                         }

                     }

                 }

                 catch ( ExpressionEvaluationException e )

                 {

                     throw new PluginConfigurationException( goal.getPluginDescriptor(), e.getMessage(), e );

                 }

                 // only mark as invalid if there are no child nodes

                 if ( ( fieldValue == null ) && ( ( value == null ) || ( value.getChildCount() == 0 ) ) )

                 {

                     parameter.setExpression( expression );

                     invalidParameters.add( parameter );

                 }

             }

         }

         if ( !invalidParameters.isEmpty() )

         {

             throw new PluginParameterException( goal, invalidParameters );

         }

     }

     private void validatePomConfiguration( MojoDescriptor goal,

                                            PlexusConfiguration pomConfiguration )

         throws PluginConfigurationException

     {

         List parameters = goal.getParameters();

         if ( parameters == null )

         {

             return;

         }

         for ( int i = 0; i < parameters.size(); i++ )

         {

             Parameter parameter = (Parameter) parameters.get( i );

             // the key for the configuration map we're building.

             String key = parameter.getName();

             PlexusConfiguration value = pomConfiguration.getChild( key, false );

             if ( ( value == null ) && StringUtils.isNotEmpty( parameter.getAlias() ) )

             {

                 key = parameter.getAlias();

                 value = pomConfiguration.getChild( key, false );

             }

             if ( value != null )

             {

                 // Make sure the parameter is either editable/configurable, or else is NOT specified in the POM

                 if ( !parameter.isEditable() )

                 {

                     StringBuffer errorMessage = new StringBuffer()

                         .append( "ERROR: Cannot override read-only parameter: " );

                     errorMessage.append( key );

                     errorMessage.append( " in goal: " ).append( goal.getFullGoalName() );

                     throw new PluginConfigurationException( goal.getPluginDescriptor(), errorMessage.toString() );

                 }

                 String deprecated = parameter.getDeprecated();

                 if ( StringUtils.isNotEmpty( deprecated ) )

                 {

                     getLogger().warn( "DEPRECATED [" + parameter.getName() + "]: " + deprecated );

                 }

             }

         }

     }

     private PlexusConfiguration mergeMojoConfiguration( XmlPlexusConfiguration fromPom,

                                                         MojoDescriptor mojoDescriptor )

     {

         XmlPlexusConfiguration result = new XmlPlexusConfiguration( fromPom.getName() );

         result.setValue( fromPom.getValue( null ) );

         if ( mojoDescriptor.getParameters() != null )

         {

             PlexusConfiguration fromMojo = mojoDescriptor.getMojoConfiguration();

             for ( Iterator it = mojoDescriptor.getParameters().iterator(); it.hasNext(); )

             {

                 Parameter parameter = (Parameter) it.next();

                 String paramName = parameter.getName();

                 String alias = parameter.getAlias();

                 String implementation = parameter.getImplementation();

                 PlexusConfiguration pomConfig = fromPom.getChild( paramName );

                 PlexusConfiguration aliased = null;

                 if ( alias != null )

                 {

                     aliased = fromPom.getChild( alias );

                 }

                 PlexusConfiguration mojoConfig = fromMojo.getChild( paramName, false );

                 // first we'll merge configurations from the aliased and real params.

                 // TODO: Is this the right thing to do?

                 if ( aliased != null )

                 {

                     if ( pomConfig == null )

                     {

                         pomConfig = new XmlPlexusConfiguration( paramName );

                     }

                     pomConfig = buildTopDownMergedConfiguration( pomConfig, aliased );

                 }

                 PlexusConfiguration toAdd = null;

                 if ( pomConfig != null )

                 {

                     pomConfig = buildTopDownMergedConfiguration( pomConfig, mojoConfig );

                     if ( StringUtils.isNotEmpty( pomConfig.getValue( null ) ) || ( pomConfig.getChildCount() > 0 ) )

                     {

                         toAdd = pomConfig;

                     }

                 }

                 if ( ( toAdd == null ) && ( mojoConfig != null ) )

                 {

                     toAdd = copyConfiguration( mojoConfig );

                 }

                 if ( toAdd != null )

                 {

                     if ( ( implementation != null ) && ( toAdd.getAttribute( "implementation", null ) == null ) )

                     {

                         XmlPlexusConfiguration implementationConf = new XmlPlexusConfiguration( paramName );

                         implementationConf.setAttribute( "implementation", parameter.getImplementation() );

                         toAdd = buildTopDownMergedConfiguration( toAdd, implementationConf );

                     }

                     result.addChild( toAdd );

                 }

             }

         }

         return result;

     }

     private XmlPlexusConfiguration buildTopDownMergedConfiguration( PlexusConfiguration dominant,

                                                                     PlexusConfiguration recessive )

     {

         XmlPlexusConfiguration result = new XmlPlexusConfiguration( dominant.getName() );

         String value = dominant.getValue( null );

         if ( StringUtils.isEmpty( value ) && ( recessive != null ) )

         {

             value = recessive.getValue( null );

         }

         if ( StringUtils.isNotEmpty( value ) )

         {

             result.setValue( value );

         }

         String[] attributeNames = dominant.getAttributeNames();

         for ( int i = 0; i < attributeNames.length; i++ )

         {

             String attributeValue = dominant.getAttribute( attributeNames[i], null );

             result.setAttribute( attributeNames[i], attributeValue );

         }

         if ( recessive != null )

         {

             attributeNames = recessive.getAttributeNames();

             for ( int i = 0; i < attributeNames.length; i++ )

             {

                 String attributeValue = recessive.getAttribute( attributeNames[i], null );

                 // TODO: recessive seems to be dominant here?

                 result.setAttribute( attributeNames[i], attributeValue );

             }

         }

         PlexusConfiguration[] children = dominant.getChildren();

         for ( int i = 0; i < children.length; i++ )

         {

             PlexusConfiguration childDom = children[i];

             PlexusConfiguration childRec = recessive == null ? null : recessive.getChild( childDom.getName(), false );

             if ( childRec != null )

             {

                 result.addChild( buildTopDownMergedConfiguration( childDom, childRec ) );

             }

             else

             {   // FIXME: copy, or use reference?

                 result.addChild( copyConfiguration( childDom ) );

             }

         }

         return result;

     }

     public static PlexusConfiguration copyConfiguration( PlexusConfiguration src )

     {

         // TODO: shouldn't be necessary

         XmlPlexusConfiguration dom = new XmlPlexusConfiguration( src.getName() );

         dom.setValue( src.getValue( null ) );

         String[] attributeNames = src.getAttributeNames();

         for ( int i = 0; i < attributeNames.length; i++ )

         {

             String attributeName = attributeNames[i];

             dom.setAttribute( attributeName, src.getAttribute( attributeName, null ) );

         }

         PlexusConfiguration[] children = src.getChildren();

         for ( int i = 0; i < children.length; i++ )

         {

             dom.addChild( copyConfiguration( children[i] ) );

         }

         return dom;

     }

     // ----------------------------------------------------------------------

     // Mojo Parameter Handling

     // ----------------------------------------------------------------------

     private void populatePluginFields( Mojo plugin,

                                        MojoDescriptor mojoDescriptor,

                                        PlexusConfiguration configuration,

                                        PlexusContainer pluginContainer,