}

    /**
     * Helper method to simplify null processing
     *
     * @param scope a scope or {@code null}
     * @return the provided scope or DEFAULT_SCOPE
     */
    public static ArtifactScopeEnum checkScope(ArtifactScopeEnum scope) {
        return scope == null ? DEFAULT_SCOPE : scope;
    }

    /**
     *
     * @return unsafe String representation of this scope.
     */
    public String getScope() {

                    if (v == 0) {
                        if (compareScope) {
                            String s1 = ArtifactScopeEnum.checkScope(md.artifactScope)
                                    .getScope();
                            String s2 = ArtifactScopeEnum.checkScope(vmd.artifactScope)
                                    .getScope();
                            return s1.compareTo(s2);
                        } else {

            MetadataGraphEdge e = (MetadataGraphEdge) o;

            return objectsEqual(version, e.version)
                    && ArtifactScopeEnum.checkScope(scope)
                            .getScope()
                            .equals(ArtifactScopeEnum.checkScope(e.scope).getScope())
                    && depth == e.depth;
        }
        return false;
    }

    public MetadataTreeNode(ArtifactMetadata md, MetadataTreeNode parent, boolean resolved, ArtifactScopeEnum scope) {
        if (md != null) {
            md.setArtifactScope(ArtifactScopeEnum.checkScope(scope));
            md.setResolved(resolved);
        }

        this.md = md;
        this.parent = parent;
    }
    // ------------------------------------------------------------------------

    // -------------------------------------------------------------------------------------------
    public ClasspathContainer(ArtifactScopeEnum scope) {
        this.scope = ArtifactScopeEnum.checkScope(scope);
    }

    // -------------------------------------------------------------------------------------------
    public ClasspathContainer(List<ArtifactMetadata> classpath, ArtifactScopeEnum scope) {

            // edge case - single vertex graph
            if (vertices.size() == 1) {
                return new MetadataGraph(entry);
            }

            final ArtifactScopeEnum requestedScope = ArtifactScopeEnum.checkScope(scope);

            MetadataGraph res = new MetadataGraph(vertices.size());
            res.setVersionedVertices(false);
            res.setScopedVertices(false);