/**
     * the entry point we started building the graph from
     */
    MetadataGraphVertex entry;

    // graph vertices
    TreeSet<MetadataGraphVertex> vertices;

    /**
     * incident and excident edges per node
     */
    Map<MetadataGraphVertex, List<MetadataGraphEdge>> incidentEdges;

    Map<MetadataGraphVertex, List<MetadataGraphEdge>> excidentEdges;

    /**
     *  null in dirty graph, actual

        // now - drop vertices
        TreeSet<MetadataGraphVertex> vertices = g.getVertices();
        for (MetadataGraphVertex v : dropList) {
            vertices.remove(v);
        }

        return g;
    }

    // -------------------------------------------------------------------------------------
    private void visit(MetadataGraphVertex from, List<MetadataGraphVertex> visited, MetadataGraph graph) {

                ArtifactMetadata amd = cleanGraph.getEntry().getMd();
                cpc.add(amd);
            } else {
                ClasspathGraphVisitor v = new ClasspathGraphVisitor(cleanGraph, cpc);
                MetadataGraphVertex entry = cleanGraph.getEntry();
                // entry point
                v.visit(entry);
            }

            return cpc;
        } catch (GraphConflictResolutionException e) {