DefaultVersionsHelper.java

package org.codehaus.mojo.versions.api;

/*
 * 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.BufferedInputStream;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import java.nio.file.Files;
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.List;
import java.util.Map;
import java.util.Set;
import java.util.TreeMap;
import java.util.TreeSet;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;
import java.util.regex.Pattern;
import java.util.stream.Collectors;

import org.apache.commons.lang3.tuple.ImmutablePair;
import org.apache.commons.lang3.tuple.Pair;
import org.apache.maven.artifact.Artifact;
import org.apache.maven.artifact.ArtifactUtils;
import org.apache.maven.artifact.manager.WagonManager;
import org.apache.maven.artifact.metadata.ArtifactMetadataRetrievalException;
import org.apache.maven.artifact.metadata.ArtifactMetadataSource;
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.ArtifactResolver;
import org.apache.maven.artifact.versioning.ArtifactVersion;
import org.apache.maven.artifact.versioning.DefaultArtifactVersion;
import org.apache.maven.execution.MavenSession;
import org.apache.maven.model.Dependency;
import org.apache.maven.model.Plugin;
import org.apache.maven.plugin.MojoExecution;
import org.apache.maven.plugin.MojoExecutionException;
import org.apache.maven.plugin.logging.Log;
import org.apache.maven.project.MavenProject;
import org.apache.maven.repository.RepositorySystem;
import org.apache.maven.settings.Settings;
import org.apache.maven.wagon.ConnectionException;
import org.apache.maven.wagon.ResourceDoesNotExistException;
import org.apache.maven.wagon.TransferFailedException;
import org.apache.maven.wagon.UnsupportedProtocolException;
import org.apache.maven.wagon.Wagon;
import org.apache.maven.wagon.authentication.AuthenticationException;
import org.apache.maven.wagon.authorization.AuthorizationException;
import org.codehaus.mojo.versions.PluginUpdatesDetails;
import org.codehaus.mojo.versions.Property;
import org.codehaus.mojo.versions.model.IgnoreVersion;
import org.codehaus.mojo.versions.model.Rule;
import org.codehaus.mojo.versions.model.RuleSet;
import org.codehaus.mojo.versions.model.io.xpp3.RuleXpp3Reader;
import org.codehaus.mojo.versions.ordering.VersionComparator;
import org.codehaus.mojo.versions.ordering.VersionComparators;
import org.codehaus.mojo.versions.utils.DependencyBuilder;
import org.codehaus.mojo.versions.utils.DependencyComparator;
import org.codehaus.mojo.versions.utils.PluginComparator;
import org.codehaus.mojo.versions.utils.RegexUtils;
import org.codehaus.mojo.versions.utils.VersionsExpressionEvaluator;
import org.codehaus.mojo.versions.utils.WagonUtils;
import org.codehaus.plexus.component.configurator.expression.ExpressionEvaluationException;
import org.codehaus.plexus.component.configurator.expression.ExpressionEvaluator;
import org.codehaus.plexus.util.StringUtils;
import org.codehaus.plexus.util.xml.pull.XmlPullParserException;

/**
 * Helper class that provides common functionality required by both the mojos and the reports.
 *
 * @author Stephen Connolly
 * @since 1.0-alpha-3
 */
public class DefaultVersionsHelper
    implements VersionsHelper
{
    private static final String CLASSPATH_PROTOCOL = "classpath";

    private static final String TYPE_EXACT = "exact";

    private static final String TYPE_REGEX = "regex";

    private static final int LOOKUP_PARALLEL_THREADS = 5;

    /**
     * The artifact comparison rules to use.
     *
     * @since 1.0-alpha-3
     */
    private RuleSet ruleSet;

    /**
     * The artifact metadata source to use.
     *
     * @since 1.0-alpha-3
     */
    private ArtifactMetadataSource artifactMetadataSource;

    /**
     * The local repository to consult.
     *
     * @since 1.0-alpha-3
     */
    private ArtifactRepository localRepository;

    /**
     * The remote artifact repositories to consult.
     *
     * @since 1.0-alpha-3
     */
    private List<ArtifactRepository> remoteArtifactRepositories;

    /**
     * The remote plugin repositories to consult.
     *
     * @since 1.0-alpha-3
     */
    private List<ArtifactRepository> remotePluginRepositories;

    private RepositorySystem repositorySystem;

    /**
     * The {@link Log} to send log messages to.
     *
     * @since 1.0-alpha-3
     */
    private Log log;

    /**
     * The maven session.
     *
     * @since 1.0-beta-1
     */
    private MavenSession mavenSession;

    /**
     * The artifact resolver.
     *
     * @since 1.3
     */
    private ArtifactResolver artifactResolver;

    private MojoExecution mojoExecution;

    /**
     * A cache mapping artifacts to their best fitting rule, since looking up
     * this information can be quite costly.
     *
     * @since 2.12
     */
    private final Map<String, Rule> artifactBestFitRule = new HashMap<>();

    /**
     * Private constructor used by the builder
     */
    private DefaultVersionsHelper()
    {
    }

    @Deprecated
    private static RuleSet getRuleSet( Wagon wagon, String remoteURI )
        throws IOException, AuthorizationException, TransferFailedException, ResourceDoesNotExistException
    {
        File tempFile = File.createTempFile( "ruleset", ".xml" );
        try
        {
            wagon.get( remoteURI, tempFile );
            try ( InputStream is = Files.newInputStream( tempFile.toPath() ) )
            {
                return readRulesFromStream( is );
            }
        }
        finally
        {
            if ( !tempFile.delete() )
            {
                // maybe we can delete this later
                tempFile.deleteOnExit();
            }
        }
    }

    private static RuleSet readRulesFromStream( InputStream stream )
        throws IOException
    {
        RuleXpp3Reader reader = new RuleXpp3Reader();
        try ( BufferedInputStream bis = new BufferedInputStream( stream ) )
        {
            return reader.read( bis );
        }
        catch ( XmlPullParserException e )
        {
            throw new IOException( e );
        }
    }

    static boolean exactMatch( String wildcardRule, String value )
    {
        Pattern p = Pattern.compile( RegexUtils.convertWildcardsToRegex( wildcardRule, true ) );
        return p.matcher( value ).matches();
    }

    static boolean match( String wildcardRule, String value )
    {
        Pattern p = Pattern.compile( RegexUtils.convertWildcardsToRegex( wildcardRule, false ) );
        return p.matcher( value ).matches();
    }

    /**
     * <p>Creates the enriched version of the ruleSet given as parameter; the ruleSet will contain the
     * set of ignored versions passed on top of its own (if defined).</p>
     *
     * <p>If the {@code originalRuleSet} is {@code null}, a new {@linkplain RuleSet} will be created as
     * a result.</p>
     *
     * <p><em>The method does not change the {@code originalRuleSet} object.</em></p>
     *
     * @param ignoredVersions collection of ignored version to enrich the clone of the original rule set
     * @param originalRuleSet original rule set
     * @return new RuleSet object containing the (if passed) cloned version of the rule set, enriched with
     *         the given set of ignored versions
     */
    @SuppressWarnings( "checkstyle:AvoidNestedBlocks" )
    private static RuleSet enrichRuleSet( Collection<String> ignoredVersions, RuleSet originalRuleSet )
    {
        RuleSet ruleSet = new RuleSet();
        if ( originalRuleSet != null )
        {
            ruleSet.setComparisonMethod( originalRuleSet.getComparisonMethod() );
            if ( originalRuleSet.getRules() != null )
            {
                ruleSet.setRules( new ArrayList<>( originalRuleSet.getRules() ) );
            }
            if ( originalRuleSet.getIgnoreVersions() != null )
            {
                ruleSet.setIgnoreVersions( new ArrayList<>( originalRuleSet.getIgnoreVersions() ) );
            }
        }

        if ( ruleSet.getIgnoreVersions() == null )
        {
            ruleSet.setIgnoreVersions( new ArrayList<>() );
        }
        ruleSet.getIgnoreVersions().addAll( ignoredVersions.stream().map( v ->
        {
            IgnoreVersion ignoreVersion = new IgnoreVersion();
            ignoreVersion.setType( TYPE_REGEX );
            ignoreVersion.setVersion( v );
            return ignoreVersion;
        } ).collect( Collectors.toList() ) );

        return ruleSet;
    }

    private static RuleSet getRulesFromClasspath( String uri, Log logger )
        throws MojoExecutionException
    {
        logger.debug( "Going to load rules from \"" + uri + "\"" );

        String choppedUrl = uri.substring( CLASSPATH_PROTOCOL.length() + 3 );

        URL url = DefaultVersionsHelper.class.getResource( choppedUrl );

        if ( null == url )
        {
            String message = "Resource \"" + uri + "\" not found in classpath.";

            throw new MojoExecutionException( message );
        }

        try
        {
            RuleSet rules = readRulesFromStream( url.openStream() );
            logger.debug( "Loaded rules from \"" + uri + "\" successfully" );
            return rules;
        }
        catch ( IOException e )
        {
            throw new MojoExecutionException( "Could not load specified rules from " + uri, e );
        }
    }

    private static RuleSet getRulesViaWagon( String rulesUri, Log logger, String serverId, String id,
                                             WagonManager wagonManager, Settings settings )
        throws MojoExecutionException
    {
        RuleSet loadedRules;

        int split = rulesUri.lastIndexOf( '/' );
        String baseUri = rulesUri;
        String fileUri = "";

        if ( split != -1 )
        {
            baseUri = rulesUri.substring( 0, split ) + '/';
            fileUri = split + 1 < rulesUri.length() ? rulesUri.substring( split + 1 ) : "";
        }

        try
        {
            Wagon wagon = WagonUtils.createWagon( serverId, baseUri, wagonManager, settings, logger );
            try
            {
                logger.debug( "Trying to load ruleset from file \"" + fileUri + "\" in " + baseUri );
                loadedRules = getRuleSet( wagon, fileUri );
            }
            finally
            {
                logger.debug( "Rule set loaded" );

                if ( wagon != null )
                {
                    try
                    {
                        wagon.disconnect();
                    }
                    catch ( ConnectionException e )
                    {
                        logger.warn( "Could not disconnect wagon!", e );
                    }
                }
            }
        }
        catch ( TransferFailedException e )
        {
            throw new MojoExecutionException( "Could not transfer rules from " + rulesUri, e );
        }
        catch ( AuthorizationException e )
        {
            throw new MojoExecutionException( "Authorization failure trying to load rules from " + rulesUri, e );
        }
        catch ( ResourceDoesNotExistException | IOException e )
        {
            throw new MojoExecutionException( "Could not load specified rules from " + rulesUri, e );
        }
        catch ( AuthenticationException e )
        {
            throw new MojoExecutionException( "Authentication failure trying to load rules from " + rulesUri, e );
        }
        catch ( UnsupportedProtocolException e )
        {
            throw new MojoExecutionException( "Unsupported protocol for " + rulesUri, e );
        }
        catch ( ConnectionException e )
        {
            throw new MojoExecutionException( "Could not establish connection to " + rulesUri, e );
        }

        return loadedRules;
    }

    static boolean isClasspathUri( String uri )
    {
        return ( uri != null && uri.startsWith( CLASSPATH_PROTOCOL + ":" ) );
    }

    @Override
    public Log getLog()
    {
        return log;
    }

    @Override
    public ArtifactVersions lookupArtifactVersions( Artifact artifact, boolean usePluginRepositories )
        throws ArtifactMetadataRetrievalException
    {
        List<ArtifactRepository> remoteRepositories = usePluginRepositories
                ? remotePluginRepositories : remoteArtifactRepositories;
        final List<ArtifactVersion> versions =
            artifactMetadataSource.retrieveAvailableVersions( artifact, localRepository, remoteRepositories );
        final List<IgnoreVersion> ignoredVersions = getIgnoredVersions( artifact );
        if ( !ignoredVersions.isEmpty() )
        {
            if ( getLog().isDebugEnabled() )
            {
                getLog().debug( "Found ignored versions: " + showIgnoredVersions( ignoredVersions ) );
            }

            final Iterator<ArtifactVersion> i = versions.iterator();
            while ( i.hasNext() )
            {
                final String version = i.next().toString();
                for ( final IgnoreVersion ignoreVersion : ignoredVersions )
                {
                    if ( TYPE_REGEX.equals( ignoreVersion.getType() ) )
                    {
                        Pattern p = Pattern.compile( ignoreVersion.getVersion() );
                        if ( p.matcher( version ).matches() )
                        {
                            if ( getLog().isDebugEnabled() )
                            {
                                getLog().debug( "Version " + version + " for artifact "
                                                    + ArtifactUtils.versionlessKey( artifact )
                                                    + " found on ignore list: "
                                                    + ignoreVersion );
                            }
                            i.remove();
                            break;
                        }
                    }
                    else if ( TYPE_EXACT.equals( ignoreVersion.getType() ) )
                    {
                        if ( version.equals( ignoreVersion.getVersion() ) )
                        {
                            if ( getLog().isDebugEnabled() )
                            {
                                getLog().debug( "Version " + version + " for artifact "
                                                    + ArtifactUtils.versionlessKey( artifact )
                                                    + " found on ignore list: "
                                                    + ignoreVersion );
                            }
                            i.remove();
                            break;
                        }
                    }
                }
            }
        }
        return new ArtifactVersions( artifact, versions, getVersionComparator( artifact ) );
    }

    /**
     * Returns a list of versions which should not be considered when looking for updates.
     *
     * @param artifact The artifact
     * @return List of ignored version
     */
    private List<IgnoreVersion> getIgnoredVersions( Artifact artifact )
    {
        final List<IgnoreVersion> ret = new ArrayList<>();

        for ( final IgnoreVersion ignoreVersion : ruleSet.getIgnoreVersions() )
        {
            if ( !TYPE_EXACT.equals( ignoreVersion.getType() ) && !TYPE_REGEX.equals( ignoreVersion.getType() ) )
            {
                getLog().warn( "The type attribute '" + ignoreVersion.getType() + "' for global ignoreVersion["
                                   + ignoreVersion + "] is not valid." + " Please use either '" + TYPE_EXACT + "' or '"
                                   + TYPE_REGEX
                                   + "'." );
            }
            else
            {
                ret.add( ignoreVersion );
            }
        }

        final Rule rule = getBestFitRule( artifact.getGroupId(), artifact.getArtifactId() );

        if ( rule != null )
        {
            for ( IgnoreVersion ignoreVersion : rule.getIgnoreVersions() )
            {
                if ( !TYPE_EXACT.equals( ignoreVersion.getType() ) && !TYPE_REGEX.equals( ignoreVersion.getType() ) )
                {
                    getLog().warn( "The type attribute '" + ignoreVersion.getType() + "' for " + rule + " is not valid."
                                       + " Please use either '" + TYPE_EXACT + "' or '" + TYPE_REGEX + "'." );
                }
                else
                {
                    ret.add( ignoreVersion );
                }
            }
        }

        return ret;
    }

    /**
     * Pretty print a list of ignored versions.
     *
     * @param ignoredVersions A list of ignored versions
     * @return A String representation of the list
     */
    private String showIgnoredVersions( List<IgnoreVersion> ignoredVersions )
    {
        StringBuilder buf = new StringBuilder();
        Iterator<IgnoreVersion> iterator = ignoredVersions.iterator();
        while ( iterator.hasNext() )
        {
            IgnoreVersion ignoreVersion = iterator.next();
            buf.append( ignoreVersion );
            if ( iterator.hasNext() )
            {
                buf.append( ", " );
            }
        }
        return buf.toString();
    }

    @Override
    public void resolveArtifact( Artifact artifact, boolean usePluginRepositories )
        throws ArtifactResolutionException, ArtifactNotFoundException
    {
        List<ArtifactRepository> remoteRepositories =
            usePluginRepositories ? remotePluginRepositories : remoteArtifactRepositories;
        artifactResolver.resolve( artifact, remoteRepositories, localRepository );
    }

    @Override
    public VersionComparator getVersionComparator( Artifact artifact )
    {
        return getVersionComparator( artifact.getGroupId(), artifact.getArtifactId() );
    }

    @Override
    public VersionComparator getVersionComparator( String groupId, String artifactId )
    {
        Rule rule = getBestFitRule( groupId, artifactId );
        final String comparisonMethod = rule == null ? ruleSet.getComparisonMethod() : rule.getComparisonMethod();
        return VersionComparators.getVersionComparator( comparisonMethod );
    }

    /**
     * Find the rule, if any, which best fits the artifact details given.
     *
     * @param groupId    Group id of the artifact
     * @param artifactId Artifact id of the artifact
     * @return Rule which best describes the given artifact
     */
    protected Rule getBestFitRule( String groupId, String artifactId )
    {
        String groupArtifactId = groupId + ':' + artifactId;
        if ( artifactBestFitRule.containsKey( groupArtifactId ) )
        {
            return artifactBestFitRule.get( groupArtifactId );
        }

        Rule bestFit = null;
        final List<Rule> rules = ruleSet.getRules();
        int bestGroupIdScore = Integer.MAX_VALUE;
        int bestArtifactIdScore = Integer.MAX_VALUE;
        boolean exactGroupId = false;
        boolean exactArtifactId = false;
        for ( Rule rule : rules )
        {
            int groupIdScore = RegexUtils.getWildcardScore( rule.getGroupId() );
            if ( groupIdScore > bestGroupIdScore )
            {
                continue;
            }
            boolean exactMatch = exactMatch( rule.getGroupId(), groupId );
            boolean match = exactMatch || match( rule.getGroupId(), groupId );
            if ( !match || ( exactGroupId && !exactMatch ) )
            {
                continue;
            }
            if ( bestGroupIdScore > groupIdScore )
            {
                bestArtifactIdScore = Integer.MAX_VALUE;
                exactArtifactId = false;
            }
            bestGroupIdScore = groupIdScore;
            if ( exactMatch && !exactGroupId )
            {
                exactGroupId = true;
                bestArtifactIdScore = Integer.MAX_VALUE;
                exactArtifactId = false;
            }
            int artifactIdScore = RegexUtils.getWildcardScore( rule.getArtifactId() );
            if ( artifactIdScore > bestArtifactIdScore )
            {
                continue;
            }
            exactMatch = exactMatch( rule.getArtifactId(), artifactId );
            match = exactMatch || match( rule.getArtifactId(), artifactId );
            if ( !match || ( exactArtifactId && !exactMatch ) )
            {
                continue;
            }
            bestArtifactIdScore = artifactIdScore;
            if ( exactMatch && !exactArtifactId )
            {
                exactArtifactId = true;
            }
            bestFit = rule;
        }

        artifactBestFitRule.put( groupArtifactId, bestFit );
        return bestFit;
    }

    @Override
    public Artifact createPluginArtifact( String groupId, String artifactId, String version )
    {
        Plugin plugin = new Plugin();
        plugin.setGroupId( groupId );
        plugin.setArtifactId( artifactId );
        plugin.setVersion( StringUtils.isNotBlank( version ) ? version : "[0,]" );
        return repositorySystem.createPluginArtifact( plugin );
    }

    @Override
    public Artifact createDependencyArtifact( String groupId, String artifactId, String version, String type,
                                              String classifier, String scope, boolean optional )
    {
        return repositorySystem.createDependencyArtifact( DependencyBuilder.newBuilder()
                .withGroupId( groupId )
                .withArtifactId( artifactId )
                .withType( type )
                .withClassifier( classifier )
                .withScope( scope )
                .withOptional( optional )
                .withVersion( StringUtils.isNotBlank( version ) ? version : "[0,]" )
                .build() );
    }

    @Override
    public Artifact createDependencyArtifact( String groupId, String artifactId, String version, String type,
                                              String classifier, String scope )
    {
        return createDependencyArtifact( groupId, artifactId, version, type, classifier, scope, false );
    }

    @Override
    public Artifact createDependencyArtifact( Dependency dependency )
    {
        if ( StringUtils.isBlank( dependency.getVersion() ) )
        {
            dependency = dependency.clone();
            dependency.setVersion( "[,0]" );
        }

        return repositorySystem.createDependencyArtifact( dependency );
    }

    @Override
    public Set<Artifact> extractArtifacts( Collection<MavenProject> mavenProjects )
    {
        Set<Artifact> result = new HashSet<>();
        for ( MavenProject project : mavenProjects )
        {
            result.add( project.getArtifact() );
        }

        return result;
    }

    @Override
    public ArtifactVersion createArtifactVersion( String version )
    {
        return new DefaultArtifactVersion( version );
    }

    /**
     * Returns a map of all possible updates per dependency. The lookup is done in parallel using
     * {@code LOOKUP_PARALLEL_THREADS} threads.
     *
     * @param dependencies The set of {@link Dependency} instances to look up.
     * @param usePluginRepositories Search the plugin repositories.
     * @return map containing the ArtifactVersions object per dependency
     * @throws ArtifactMetadataRetrievalException if the lookup does not succeed
     */
    @Override
    public Map<Dependency, ArtifactVersions> lookupDependenciesUpdates( Set<Dependency> dependencies,
                                                                        boolean usePluginRepositories )
        throws ArtifactMetadataRetrievalException
    {
        ExecutorService executor = Executors.newFixedThreadPool( LOOKUP_PARALLEL_THREADS );
        try
        {
            Map<Dependency, ArtifactVersions> dependencyUpdates = new TreeMap<>( DependencyComparator.INSTANCE );
            List<Future<? extends Pair<Dependency, ArtifactVersions>>> futures = dependencies.stream()
                    .map( dependency -> executor.submit( () -> new ImmutablePair<>
                            ( dependency, lookupDependencyUpdates( dependency, usePluginRepositories ) ) ) )
                    .collect( Collectors.toList() );
            for ( Future<? extends Pair<Dependency, ArtifactVersions>> details : futures )
            {
                Pair<Dependency, ArtifactVersions> pair = details.get();
                dependencyUpdates.put( pair.getKey(), pair.getValue() );
            }

            return dependencyUpdates;
        }
        catch ( ExecutionException | InterruptedException ie )
        {
            throw new ArtifactMetadataRetrievalException( "Unable to acquire metadata for dependencies " + dependencies
                    + ": " + ie.getMessage(), ie, null );
        }
        finally
        {
            executor.shutdown();
        }
    }

    @Override
    public ArtifactVersions lookupDependencyUpdates( Dependency dependency, boolean usePluginRepositories )
        throws ArtifactMetadataRetrievalException
    {
        ArtifactVersions allVersions = lookupArtifactVersions( createDependencyArtifact( dependency ),
                usePluginRepositories );
        return new ArtifactVersions( allVersions.getArtifact(), Arrays.stream( allVersions.getAllUpdates() )
                .collect( Collectors.toList() ), allVersions.getVersionComparator() );
    }

    @Override
    public Map<Plugin, PluginUpdatesDetails> lookupPluginsUpdates( Set<Plugin> plugins, boolean allowSnapshots )
        throws ArtifactMetadataRetrievalException
    {
        ExecutorService executor = Executors.newFixedThreadPool( LOOKUP_PARALLEL_THREADS );
        try
        {
            Map<Plugin, PluginUpdatesDetails> pluginUpdates = new TreeMap<>( PluginComparator.INSTANCE );
            List<Future<? extends Pair<Plugin, PluginUpdatesDetails>>> futures = plugins.stream()
                    .map( p -> executor.submit( () -> new ImmutablePair<>
                            ( p, lookupPluginUpdates( p, allowSnapshots ) ) ) )
                    .collect( Collectors.toList() );
            for ( Future<? extends Pair<Plugin, PluginUpdatesDetails>> details : futures )
            {
                Pair<Plugin, PluginUpdatesDetails> pair = details.get();
                pluginUpdates.put( pair.getKey(), pair.getValue() );
            }

            return pluginUpdates;
        }
        catch ( ExecutionException | InterruptedException ie )
        {
            throw new ArtifactMetadataRetrievalException( "Unable to acquire metadata for plugins " + plugins + ": "
                    + ie.getMessage(), ie, null );
        }
        finally
        {
            executor.shutdown();
        }
    }

    @Override
    public PluginUpdatesDetails lookupPluginUpdates( Plugin plugin, boolean allowSnapshots )
        throws ArtifactMetadataRetrievalException
    {
        String version = plugin.getVersion() != null
                ? plugin.getVersion()
                : "LATEST";

        Set<Dependency> pluginDependencies = new TreeSet<>( DependencyComparator.INSTANCE );
        if ( plugin.getDependencies() != null )
        {
            pluginDependencies.addAll( plugin.getDependencies() );
        }
        Map<Dependency, ArtifactVersions> pluginDependencyDetails =
            lookupDependenciesUpdates( pluginDependencies, false );

        ArtifactVersions allVersions =
                lookupArtifactVersions( createPluginArtifact( plugin.getGroupId(), plugin.getArtifactId(), version ),
                        true );
        ArtifactVersions updatedVersions = new ArtifactVersions( allVersions.getArtifact(),
                Arrays.stream( allVersions.getAllUpdates() ).collect( Collectors.toList() ),
                allVersions.getVersionComparator() );
        return new PluginUpdatesDetails( updatedVersions, pluginDependencyDetails, allowSnapshots );
    }

    @Override
    public ExpressionEvaluator getExpressionEvaluator( MavenProject project )
    {
        return new VersionsExpressionEvaluator( mavenSession, mojoExecution );
    }

    @Override
    public Map<Property, PropertyVersions> getVersionPropertiesMap( MavenProject project,
                                                                    Property[] propertyDefinitions,
                                                                    String includeProperties,
                                                                    String excludeProperties,
                                                                    boolean includeParent,
                                                                    boolean autoLinkItems )
        throws MojoExecutionException
    {
        Map<String, Property> properties = new HashMap<>();
        if ( propertyDefinitions != null )
        {
            for ( Property propertyDefinition : propertyDefinitions )
            {
                properties.put( propertyDefinition.getName(), propertyDefinition );
            }
        }
        Map<String, PropertyVersionsBuilder> builders = new HashMap<>();
        if ( autoLinkItems )
        {
            final PropertyVersionsBuilder[] propertyVersionsBuilders;
            try
            {
                propertyVersionsBuilders = PomHelper.getPropertyVersionsBuilders( this, project, includeParent );
            }
            catch ( ExpressionEvaluationException | IOException e )
            {
                throw new MojoExecutionException( e.getMessage(), e );
            }

            for ( PropertyVersionsBuilder propertyVersionsBuilder : propertyVersionsBuilders )
            {
                final String name = propertyVersionsBuilder.getName();
                builders.put( name, propertyVersionsBuilder );
                if ( !properties.containsKey( name ) )
                {
                    final Property value = new Property( name );
                    getLog().debug( "Property ${" + name + "}: Adding inferred version range of "
                                        + propertyVersionsBuilder.getVersionRange() );
                    value.setVersion( propertyVersionsBuilder.getVersionRange() );
                    properties.put( name, value );
                }
            }
        }

        List<String> includePropertiesList = getSplitProperties( includeProperties );
        List<String> excludePropertiesList = getSplitProperties( excludeProperties );

        getLog().debug( "Searching for properties associated with builders" );
        Iterator<Property> i = properties.values().iterator();
        while ( i.hasNext() )
        {
            Property property = i.next();

            getLog().debug( "includePropertiesList:" + includePropertiesList + " property: " + property.getName() );
            getLog().debug( "excludePropertiesList:" + excludePropertiesList + " property: " + property.getName() );
            if ( !includePropertiesList.isEmpty() && !includePropertiesList.contains( property.getName() ) )
            {
                getLog().debug( "Skipping property ${" + property.getName() + "}" );
                i.remove();
            }
            else if ( !excludePropertiesList.isEmpty() && excludePropertiesList.contains( property.getName() ) )
            {
                getLog().debug( "Ignoring property ${" + property.getName() + "}" );
                i.remove();
            }
        }
        i = properties.values().iterator();
        Map<Property, PropertyVersions> propertyVersions = new LinkedHashMap<>( properties.size() );
        while ( i.hasNext() )
        {
            Property property = i.next();
            getLog().debug( "Property ${" + property.getName() + "}" );
            PropertyVersionsBuilder builder = builders.get( property.getName() );
            if ( builder == null || !builder.isAssociated() )
            {
                getLog().debug( "Property ${" + property.getName() + "}: Looks like this property is not "
                                    + "associated with any dependency..." );
                builder = new PropertyVersionsBuilder( null, property.getName(), this );
            }
            if ( !property.isAutoLinkDependencies() )
            {
                getLog().debug( "Property ${" + property.getName() + "}: Removing any autoLinkDependencies" );
                builder.clearAssociations();
            }
            Dependency[] dependencies = property.getDependencies();
            if ( dependencies != null )
            {
                for ( Dependency dependency : dependencies )
                {
                    getLog().debug( "Property ${" + property.getName() + "}: Adding association to " + dependency );
                    builder.addAssociation( this.createDependencyArtifact( dependency ), false );
                }
            }
            try
            {
                final PropertyVersions versions = builder.newPropertyVersions();
                if ( property.isAutoLinkDependencies() && StringUtils.isEmpty( property.getVersion() )
                    && !StringUtils.isEmpty( builder.getVersionRange() ) )
                {
                    getLog().debug( "Property ${" + property.getName() + "}: Adding inferred version range of "
                                        + builder.getVersionRange() );
                    property.setVersion( builder.getVersionRange() );
                }
                versions.setCurrentVersion( project.getProperties().getProperty( property.getName() ) );
                propertyVersions.put( property, versions );
            }
            catch ( ArtifactMetadataRetrievalException e )
            {
                throw new MojoExecutionException( e.getMessage(), e );
            }
        }
        return propertyVersions;
    }

    private List<String> getSplitProperties( String commaSeparatedProperties )
    {
        List<String> propertiesList = Collections.emptyList();
        if ( StringUtils.isNotEmpty( commaSeparatedProperties ) )
        {
            String[] splittedProps = StringUtils.split( commaSeparatedProperties, "," );
            propertiesList = Arrays.asList( StringUtils.stripAll( splittedProps ) );
        }
        return propertiesList;
    }

    /**
     * Builder class for {@linkplain DefaultVersionsHelper}
     */
    public static class Builder
    {
        private RepositorySystem repositorySystem;
        private ArtifactResolver artifactResolver;
        private ArtifactMetadataSource artifactMetadataSource;
        private List<ArtifactRepository> remoteArtifactRepositories;
        private List<ArtifactRepository> remotePluginRepositories;
        private ArtifactRepository localRepository;
        private Collection<String> ignoredVersions;
        private RuleSet ruleSet;
        private WagonManager wagonManager;
        private Settings settings;
        private String serverId;
        private String rulesUri;
        private Log log;
        private MavenSession mavenSession;
        private MojoExecution mojoExecution;

        public Builder()
        {
        }

        public Builder withRepositorySystem( RepositorySystem repositorySystem )
        {
            this.repositorySystem = repositorySystem;
            return this;
        }

        public Builder withArtifactResolver( ArtifactResolver artifactResolver )
        {
            this.artifactResolver = artifactResolver;
            return this;
        }

        public Builder withArtifactMetadataSource( ArtifactMetadataSource artifactMetadataSource )
        {
            this.artifactMetadataSource = artifactMetadataSource;
            return this;
        }

        public Builder withRemoteArtifactRepositories(
                List<ArtifactRepository> remoteArtifactRepositories )
        {
            this.remoteArtifactRepositories = remoteArtifactRepositories;
            return this;
        }

        public Builder withRemotePluginRepositories(
                List<ArtifactRepository> remotePluginRepositories )
        {
            this.remotePluginRepositories = remotePluginRepositories;
            return this;
        }

        public Builder withLocalRepository( ArtifactRepository localRepository )
        {
            this.localRepository = localRepository;
            return this;
        }

        public Builder withIgnoredVersions( Collection<String> ignoredVersions )
        {
            this.ignoredVersions = ignoredVersions;
            return this;
        }

        public Builder withRuleSet( RuleSet ruleSet )
        {
            this.ruleSet = ruleSet;
            return this;
        }

        public Builder withWagonManager( WagonManager wagonManager )
        {
            this.wagonManager = wagonManager;
            return this;
        }

        public Builder withSettings( Settings settings )
        {
            this.settings = settings;
            return this;
        }

        public Builder withServerId( String serverId )
        {
            this.serverId = serverId;
            return this;
        }

        public Builder withRulesUri( String rulesUri )
        {
            this.rulesUri = rulesUri;
            return this;
        }

        public Builder withLog( Log log )
        {
            this.log = log;
            return this;
        }

        public Builder withMavenSession( MavenSession mavenSession )
        {
            this.mavenSession = mavenSession;
            return this;
        }

        public Builder withMojoExecution( MojoExecution mojoExecution )
        {
            this.mojoExecution = mojoExecution;
            return this;
        }

        /**
         * Builds the constructed {@linkplain DefaultVersionsHelper} object
         * @return constructed {@linkplain DefaultVersionsHelper}
         * @throws MojoExecutionException should the constructor with the Wagon go wrong
         */
        public DefaultVersionsHelper build() throws MojoExecutionException
        {
            DefaultVersionsHelper instance = new DefaultVersionsHelper();
            instance.repositorySystem = repositorySystem;
            instance.artifactResolver = artifactResolver;
            instance.mavenSession = mavenSession;
            instance.mojoExecution = mojoExecution;
            if ( ruleSet != null )
            {
                if ( !isBlank( rulesUri ) )
                {
                    log.warn( "rulesUri is ignored if rules are specified in pom or as parameters" );
                }
                instance.ruleSet = ruleSet;
            }
            else
            {
                instance.ruleSet = isBlank( rulesUri )
                        ? new RuleSet()
                        : isClasspathUri( rulesUri )
                        ? getRulesFromClasspath( rulesUri, log )
                        : getRulesViaWagon( rulesUri, log, serverId, serverId, wagonManager,
                        settings );
            }
            if ( ignoredVersions != null && !ignoredVersions.isEmpty() )
            {
                instance.ruleSet = enrichRuleSet( ignoredVersions, instance.ruleSet );
            }
            instance.artifactMetadataSource = artifactMetadataSource;
            instance.localRepository = localRepository;
            instance.remoteArtifactRepositories = remoteArtifactRepositories;
            instance.remotePluginRepositories = remotePluginRepositories;
            instance.log = log;
            return instance;
        }

        private static boolean isBlank( String s )
        {
            return s == null || s.trim().isEmpty();
        }
    }
}