RepositorySystemSession session, ArtifactDescriptorRequest request, ArtifactDescriptorResult result)
            throws ArtifactDescriptorException {
        RequestTrace trace = RequestTrace.newChild(request.getTrace(), request);

        LinkedHashSet<String> visited = new LinkedHashSet<>();
        for (Artifact a = request.getArtifact(); ; ) {
            Artifact pomArtifact = ArtifactDescriptorUtils.toPomArtifactUnconditionally(a);

            VersionRangeResult result,
            VersionRangeRequest request,
            Metadata.Nature wantedNature) {
        RequestTrace trace = RequestTrace.newChild(request.getTrace(), request);

        Map<String, ArtifactRepository> versionIndex = new HashMap<>();

        Metadata metadata = new DefaultMetadata(
                request.getArtifact().getGroupId(),

    @Override
    public VersionResult resolveVersion(RepositorySystemSession session, VersionRequest request)
            throws VersionResolutionException {
        RequestTrace trace = RequestTrace.newChild(request.getTrace(), request);

        Artifact artifact = request.getArtifact();

        String version = artifact.getVersion();

        VersionResult result = new VersionResult(request);

        Key cacheKey = null;

        requireNonNull(event, "event cannot be null");

        if (!isLocalRepositoryArtifactOrMissing(event.getSession(), event.getArtifact())) {
            return;
        }

        RequestTrace trace = event.getTrace();

        CollectStepData collectStepTrace = null;
        ArtifactRequest artifactRequest = null;
        ArtifactDescriptorRequest artifactDescriptorRequest = null;
        Plugin plugin = null;

        ModelBuilderRequestBuilder() {}

        ModelBuilderRequestBuilder(ModelBuilderRequest request) {
            this.session = request.getSession();
            this.trace = request.getTrace();
            this.requestType = request.getRequestType();
            this.locationTracking = request.isLocationTracking();
            this.recursive = request.isRecursive();
            this.source = request.getSource();

                request.addDependency(pluginDep);
            }

            DependencyRequest depRequest = new DependencyRequest(request, resolutionFilter);
            depRequest.setTrace(trace.trace());

            request.setTrace(RequestTrace.newChild(trace.trace(), depRequest));

            node = repoSystem.collectDependencies(pluginSession, request).getRoot();

            if (logger.isDebugEnabled()) {

            try {
                ArtifactRequest request = new ArtifactRequest(pomArtifact, repositories, context);
                request.setTrace(trace);
                pomArtifact = resolver.resolveArtifact(session, request).getArtifact();
            } catch (ArtifactResolutionException e) {

        Artifact pomArtifact = new DefaultArtifact(groupId, artifactId, "", "pom", version);

        try {
            ArtifactRequest request = new ArtifactRequest(pomArtifact, repositories, context);
            request.setTrace(trace);
            pomArtifact = resolver.resolveArtifact(session, request).getArtifact();
        } catch (ArtifactResolutionException e) {

            requests.add(new MetadataRequest(metadata, null, REPOSITORY_CONTEXT).setTrace(trace));

            for (RemoteRepository repository : request.getRepositories()) {
                requests.add(new MetadataRequest(metadata, repository, REPOSITORY_CONTEXT).setTrace(trace));
            }
        }

        // initial try, use locally cached metadata

        List<MetadataRequest> requests = new ArrayList<>();

        requests.add(new MetadataRequest(metadata, null, REPOSITORY_CONTEXT).setTrace(trace));

        for (RemoteRepository repository : request.getRepositories()) {
            requests.add(new MetadataRequest(metadata, repository, REPOSITORY_CONTEXT).setTrace(trace));
        }