* <p>
     * This type registry is NOT used by Maven Core: Maven replaces it during Session creation with a type registry
     * that supports extending it (i.e. via Maven Extensions).
     * <p>
     * Important: this "static" list of types should be in-sync with core provided types.
     */
    protected ArtifactTypeRegistry getArtifactTypeRegistry() {

            // extensionArtifacts
            Set<Artifact> extensionArtifacts = new HashSet<>();
            List<Extension> extensions =
                    project.getModel().getDelegate().getBuild().getExtensions();
            if (extensions != null) {
                for (Extension ext : extensions) {
                    String version;
                    if (ext.getVersion() == null || ext.getVersion().isEmpty()) {

                            p.getInherited(),
                            p.getKey(),
                            p);

                    validateBoolean(
                            "build.plugins.plugin.extensions",
                            EMPTY,
                            problems,
                            errOn30,
                            Version.V20,
                            p.getExtensions(),

     * @param extension the artifact extension, or {@code null} is unspecified
     * @return artifact with the given coordinates
     *
     * @see org.apache.maven.api.services.ArtifactFactory#create(Session, String, String, String, String)
     */
    @Nonnull
    Artifact createArtifact(String groupId, String artifactId, String version, String extension);

    /**

        String groupId = artifact.getGroupId();
        String artifactId = artifact.getArtifactId();
        String version = artifact.getBaseVersion();
        String classifier = artifact.getClassifier();
        String extension = artifact.getExtension();
        Path repo = getProjectLocalRepo();
        return repo.resolve(groupId)
                .resolve(artifactId)
                .resolve(version)
                .resolve(artifactId

        }
        return artifactGeneratorFactories;
    }

    protected Map<String, ArtifactGeneratorFactory> createArtifactGeneratorFactories() {
        // by default none, this is extension point
        return new HashMap<>();
    }

    private Map<String, ArtifactDecoratorFactory> artifactDecoratorFactories;

    public final Map<String, ArtifactDecoratorFactory> getArtifactDecoratorFactories() {

      NavigableMap<K, V> synchronizedNavigableMap(NavigableMap<K, V> navigableMap) {
    return Synchronized.navigableMap(navigableMap);
  }

  /**
   * {@code AbstractMap} extension that makes it easy to cache customized keySet, values, and
   * entrySet views.
   */
  @GwtCompatible
  abstract static class ViewCachingAbstractMap<

     */
    @Override
    public ArtifactCoordinate createArtifactCoordinate(
            String groupId, String artifactId, String version, String extension) {
        return getService(ArtifactCoordinateFactory.class).create(this, groupId, artifactId, version, extension);
    }

    /**
     * Shortcut for <code>getService(CoordinateFactory.class).create(...)</code>
     *