private DependencyNode getNode( EnforcerRuleHelper helper )
        throws EnforcerRuleException
    {
        try
        {
            MavenProject project = (MavenProject) helper.evaluate( "${project}" );
            DependencyTreeBuilder dependencyTreeBuilder =
                (DependencyTreeBuilder) helper.getComponent( DependencyTreeBuilder.class );
            ArtifactRepository repository = (ArtifactRepository) helper.evaluate( "${localRepository}" );
            ArtifactFactory factory = (ArtifactFactory) helper.getComponent( ArtifactFactory.class );
            ArtifactMetadataSource metadataSource =
                (ArtifactMetadataSource) helper.getComponent( ArtifactMetadataSource.class );
            ArtifactCollector collector = (ArtifactCollector) helper.getComponent( ArtifactCollector.class );
            ArtifactFilter filter = null; // we need to evaluate all scopes
            DependencyNode node =
                dependencyTreeBuilder.buildDependencyTree( project, repository, factory, metadataSource, filter,
                                                           collector );
            return node;
        }
        catch ( ExpressionEvaluationException e )
        {
            throw new EnforcerRuleException( "Unable to lookup an expression " + e.getLocalizedMessage(), e );
        }
        catch ( ComponentLookupException e )
        {
            throw new EnforcerRuleException( "Unable to lookup a component " + e.getLocalizedMessage(), e );
        }
        catch ( DependencyTreeBuilderException e )
        {
            throw new EnforcerRuleException( "Could not build dependency tree " + e.getLocalizedMessage(), e );
        }
    }

    public void execute( EnforcerRuleHelper helper )
        throws EnforcerRuleException
    {
        if ( log == null )
        {
            log = helper.getLog();
        }
        try
        {
            if ( i18n == null )
            {
                i18n = (I18N) helper.getComponent( I18N.class );
            }
            DependencyNode node = getNode( helper );

        return errorMessage.toString();
    }

    private StringBuilder buildTreeString( DependencyNode node )
    {
        List<String> loc = new ArrayList<String>();
        DependencyNode currentNode = node;
        while ( currentNode != null )
        {
            loc.add( getFullArtifactName( currentNode.getArtifact() ) );
            currentNode = currentNode.getParent();
        }
        Collections.reverse( loc );
        StringBuilder builder = new StringBuilder();
        for ( int i = 0; i < loc.size(); i++ )
        {
            for ( int j = 0; j < i; j++ )
            {
                builder.append( "  " );
            }
            builder.append( "+-" ).append( loc.get( i ) );