* create a custom {@code Type} for it.
     *
     * @param id the id of the type to retrieve
     * @return the type
     */
    @Nonnull
    @Override
    default Type require(@Nonnull String id) {
        return lookup(id).orElseThrow(() -> new IllegalArgumentException("Unknown extensible enum value '" + id + "'"));
    }

        return builder()
                .session(requireNonNull(session, "session cannot be null"))
                .artifactCoordinates(requireNonNull(artifactCoordinates, "artifactCoordinates cannot be null"))
                .build();
    }

    @Nonnull
    static VersionResolverRequest build(
            @Nonnull Session session,

      Class<? super @NonNull E> type, E... contents) {
    return new MinimalCollection<>(type, true, contents);
  }

  private final E[] contents;
  private final Class<? super @NonNull E> type;
  private final boolean allowNulls;

  // Package-private so that it can be extended.
  MinimalCollection(Class<? super @NonNull E> type, boolean allowNulls, E... contents) {

 * @see DependencyScope
 */
@Experimental
@Immutable
public interface PathScope extends ExtensibleEnum {

    // TODO: what if I simply want all dependencies ?
    @Nonnull
    ProjectScope projectScope();

    @Nonnull
    Set<DependencyScope> dependencyScopes();

    PathScope MAIN_COMPILE = pathScope(
            "main-compile",
            ProjectScope.MAIN,
            DependencyScope.COMPILE_ONLY,

    return ordering.<T>reverse().<@NonNull S>nullsLast();
  }

  @SuppressWarnings("unchecked") // still need the right way to explain this
  @Override
  public <S extends @Nullable T> Ordering<@Nullable S> nullsFirst() {
    return (Ordering<@Nullable S>) this;
  }

  @Override
  public <S extends @Nullable T> Ordering<@Nullable S> nullsLast() {
    return ordering.<@NonNull S>nullsLast();
  }

  @Override

        }

        @Override
        @Nonnull
        public InputStream openStream() throws IOException {
            return Files.newInputStream(path);
        }

        @Override
        @Nonnull
        public String getLocation() {
            return location;
        }

        @Override
        @Nullable
        public Source resolve(@Nonnull String relative) {

import java.io.IOException;
import java.io.InputStream;
import java.nio.file.Path;

import org.apache.maven.api.Session;
import org.apache.maven.api.annotations.Experimental;
import org.apache.maven.api.annotations.Nonnull;
import org.apache.maven.api.annotations.Nullable;

/**
 * Provides access to the contents of a source independently of the
 * backing store (e.g. file system, database, memory).
 * <p>

     * @return the version range resolver request, never {@code null}
     */
    @Nonnull
    static VersionRangeResolverRequest build(
            @Nonnull Session session, @Nonnull ArtifactCoordinates artifactCoordinates) {
        return build(session, artifactCoordinates, null, null);
    }

    /**
     * Creates a version range resolver request.

  private final Map<TypeToken<? extends @NonNull B>, B> backingMap = new HashMap<>();

  @Override
  public <T extends @NonNull B> @Nullable T getInstance(Class<T> type) {
    return trustedGet(TypeToken.of(type));
  }

  @Override
  public <T extends @NonNull B> @Nullable T getInstance(TypeToken<T> type) {
    return trustedGet(type.rejectTypeVariables());
  }

  @Override
  @CanIgnoreReturnValue

     *
     * @return the current working directory path
     */
    @Nonnull
    Path cwd();

    /**
     * Returns the Maven installation directory.
     * This is usually set by the Maven launcher script using the "maven.home" system property.
     *
     * @return the Maven installation directory path
     */
    @Nonnull
    Path installationDirectory();

    /**
     * Returns the user's home directory.