import org.apache.maven.model.resolution.UnresolvableModelException;
import org.eclipse.aether.RepositorySystem;
import org.eclipse.aether.RepositorySystemSession;
import org.eclipse.aether.RequestTrace;
import org.eclipse.aether.artifact.Artifact;
import org.eclipse.aether.artifact.DefaultArtifact;
import org.eclipse.aether.impl.RemoteRepositoryManager;
import org.eclipse.aether.repository.RemoteRepository;

import org.apache.maven.api.model.Plugin;
import org.eclipse.aether.AbstractRepositoryListener;
import org.eclipse.aether.RepositoryEvent;
import org.eclipse.aether.RepositorySystemSession;
import org.eclipse.aether.RequestTrace;
import org.eclipse.aether.artifact.Artifact;
import org.eclipse.aether.collection.CollectStepData;
import org.eclipse.aether.graph.Dependency;
import org.eclipse.aether.graph.DependencyNode;

        return new ArtifactFactoryRequestBuilder();
    }

    @NotThreadSafe
    class ArtifactFactoryRequestBuilder {
        private Session session;
        private RequestTrace trace;
        private String groupId;
        private String artifactId;
        private String version;
        private String classifier;
        private String extension;
        private String type;

        Session session;
        RequestTrace trace;
        ArtifactCoordinates artifactCoordinates;
        List<RemoteRepository> repositories;

        public VersionResolverRequestBuilder session(Session session) {
            this.session = session;
            return this;
        }

        public VersionResolverRequestBuilder trace(RequestTrace trace) {
            this.trace = trace;

                .repositories(repositories)
                .build();
    }

    @NotThreadSafe
    class ArtifactResolverRequestBuilder {
        Session session;
        RequestTrace trace;
        Collection<? extends ArtifactCoordinates> coordinates;
        List<RemoteRepository> repositories;

        ArtifactResolverRequestBuilder() {}

        @Nonnull

        }

        return result;
    }

    private PluginVersionResult resolveFromRepository(PluginVersionRequest request)
            throws PluginVersionResolutionException {
        RequestTrace trace = RequestTrace.newChild(null, request);

        DefaultPluginVersionResult result = new DefaultPluginVersionResult();

        org.eclipse.aether.metadata.Metadata metadata = new DefaultMetadata(

                .artifacts(requireNonNull(artifacts, "artifacts cannot be null"))
                .build();
    }

    class ArtifactDeployerRequestBuilder {
        Session session;
        RequestTrace trace;
        RemoteRepository repository;
        Collection<ProducedArtifact> artifacts;
        int retryFailedDeploymentCount;

        ArtifactDeployerRequestBuilder() {}

        @Nonnull

    private Model loadPom(
            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(); ; ) {

        return new ArtifactFactoryRequestBuilder();
    }

    @NotThreadSafe
    class ArtifactFactoryRequestBuilder {
        private Session session;
        private RequestTrace trace;
        private String groupId;
        private String artifactId;
        private String version;
        private String classifier;
        private String extension;
        private String type;

        ProtoSession session;
        RequestTrace trace;
        Source installationToolchainsSource;
        Source userToolchainsSource;

        public ToolchainsBuilderRequestBuilder session(ProtoSession session) {
            this.session = session;
            return this;
        }

        public ToolchainsBuilderRequestBuilder trace(RequestTrace trace) {
            this.trace = trace;