@Override
                  public SampleElements<Entry<Range<Integer>, String>> samples() {
                    return new SampleElements<>(
                        mapEntry(Range.singleton(0), "banana"),
                        mapEntry(Range.closedOpen(3, 5), "frisbee"),
                        mapEntry(Range.atMost(-1), "fruitcake"),
                        mapEntry(Range.open(10, 15), "elephant"),

 * <p>
 * Example usage:
 * <pre>
 * public class CustomProjectScopeProvider implements ProjectScopeProvider {
 *     public Collection&lt;ProjectScope&gt; provides() {
 *         return Collections.singleton(projectScope("integration-test"));
 *     }
 * }
 * </pre>
 *
 * @see org.apache.maven.api.ProjectScope
 * @see org.apache.maven.api.spi.ExtensibleEnumProvider
 * @since 4.0.0
 */
@Experimental
@Consumer

        Artifact g = createLocalArtifact("g", "1.0");

        Artifact h = createLocalArtifact("h", "1.0");

        ArtifactResolutionResult result = artifactResolver.resolveTransitively(
                Collections.singleton(g), projectArtifact, remoteRepositories(), localRepository(), null);

        printErrors(result);

        assertEquals(2, result.getArtifacts().size());

        assertTrue(result.getArtifacts().contains(g));

public final class CheckHandshake {
  /** Rejects otherwise-trusted certificates. */
  private static final Interceptor CHECK_HANDSHAKE_INTERCEPTOR = new Interceptor() {
    final Set<String> denylist = Collections.singleton(
        "sha256/afwiKY3RxoMmLkuRW1l7QsPZTJPwDS2pdDROQjXw8ig=");

    @Override public Response intercept(Chain chain) throws IOException {

    }

    List<String> visitAll() {
        return visitAll(vertices.values(), new HashMap<>(), new ArrayList<>());
    }

    List<String> findCycle(Vertex vertex) {
        return visitCycle(Collections.singleton(vertex), new HashMap<>(), new LinkedList<>());
    }

    private static List<String> visitAll(
            Collection<Vertex> children, Map<Vertex, DfsState> stateMap, List<String> list) {

 * <p>
 * Example usage:
 * <pre>
 * public class CustomLifecycleProvider implements LifecycleProvider {
 *     public Collection&lt;Lifecycle&gt; provides() {
 *         return Collections.singleton(
 *             lifecycle("deploy-docker", Arrays.asList(
 *                 "build-image",
 *                 "tag-image",
 *                 "push-image"
 *             ))
 *         );
 *     }
 * }

 * <p>
 * Example usage:
 * <pre>
 * public class CustomPathScopeProvider implements PathScopeProvider {
 *     public Collection&lt;PathScope&gt; provides() {
 *         return Collections.singleton(pathScope("integration-test",
 *                 ProjectScope.TEST, DependencyScope.TEST));
 *     }
 * }
 * </pre>
 *
 * @see org.apache.maven.api.PathScope
 * @see org.apache.maven.api.spi.ExtensibleEnumProvider

 * <p>
 * Example usage:
 * <pre>
 * public class CustomLanguageProvider implements LanguageProvider {
 *     public Collection&lt;Language&gt; provides() {
 *         return Collections.singleton(language("kotlin"));
 *     }
 * }
 * </pre>
 *
 * @see org.apache.maven.api.Language
 * @see org.apache.maven.api.spi.ExtensibleEnumProvider
 * @since 4.0.0
 */
@Experimental
@Consumer
@Named

   * specified by the given {@code builder}. The returned {@link MapMakerInternalMap} will be
   * optimized to saved memory. Since {@link MapMaker.Dummy} is a singleton, we don't need to store
   * any values at all. Because of this optimization, {@code build.getValueStrength()} must be
   * {@link Strength#STRONG}.
   *

    checkNotNull(supplier);
    return reference;
  }

  @Override
  public T orNull() {
    return reference;
  }

  @Override
  public Set<T> asSet() {
    return Collections.singleton(reference);
  }

  @Override
  public <V> Optional<V> transform(Function<? super T, V> function) {
    return new Present<>(
        checkNotNull(
            function.apply(reference),