}

    class Builder {
        private Map<String, String> userProperties;
        private Map<String, String> systemProperties;
        private Instant startTime;
        private Path topDirectory;
        private Path rootDirectory;

        private Builder() {}

        private Builder(
                Map<String, String> userProperties,
                Map<String, String> systemProperties,

  private final ImmutableMap<K, V> map;

  ImmutableMapKeySet(ImmutableMap<K, V> map) {
    this.map = map;
  }

  @Override
  public int size() {
    return map.size();
  }

  @Override
  public UnmodifiableIterator<K> iterator() {
    return map.keyIterator();
  }

  @Override
  public boolean contains(@Nullable Object object) {
    return map.containsKey(object);
  }

  @Override

      Map<K, ? extends V> map, @ParametricNullness V defaultValue) {
    return new ForMapWithDefault<>(map, defaultValue);
  }

  private static final class FunctionForMapNoDefault<
          K extends @Nullable Object, V extends @Nullable Object>
      implements Function<K, V>, Serializable {
    final Map<K, V> map;

    FunctionForMapNoDefault(Map<K, V> map) {
      this.map = checkNotNull(map);
    }

    @Override

    assertThat(map.replace(one, three)).isSameInstanceAs(two);
    assertThat(map.get(one)).isSameInstanceAs(three);
    assertThat(map.replace(one, two, three)).isFalse();
    assertThat(map.get(one)).isSameInstanceAs(three);
    assertThat(map.replace(one, three, two)).isTrue();
    assertThat(map.get(one)).isSameInstanceAs(two);
    assertThat(map).hasSize(3);

    map.clear();

public interface PropertyContributor extends SpiService {
    /**
     * Invoked just before session is created with a mutable map that carries collected user properties so far.
     *
     * @param userProperties The mutable user properties, never {@code null}.
     * @see #contribute(ProtoSession)
     */
    default void contribute(Map<String, String> userProperties) {}

    /**

            to.add(ArtifactUtils.copyArtifact(artifact));
        }
        return to;
    }

    public static <K, T extends Map<K, Artifact>> T copyArtifacts(Map<K, ? extends Artifact> from, T to) {
        if (from != null) {
            for (Map.Entry<K, ? extends Artifact> entry : from.entrySet()) {
                to.put(entry.getKey(), ArtifactUtils.copyArtifact(entry.getValue()));
            }
        }

  }

  public void testKeySet() {
    Map<String, Integer> map = create();
    Set<String> keySet = map.keySet();
    assertTrue(keySet instanceof SynchronizedSet);
    assertSame(mutex, ((SynchronizedSet<?>) keySet).mutex);
  }

  public void testValues() {
    Map<String, Integer> map = create();
    Collection<Integer> values = map.values();
    assertTrue(values instanceof SynchronizedCollection);

      implements MapDifference<K, V> {
    final Map<K, V> onlyOnLeft;
    final Map<K, V> onlyOnRight;
    final Map<K, V> onBoth;
    final Map<K, ValueDifference<V>> differences;

    MapDifferenceImpl(
        Map<K, V> onlyOnLeft,
        Map<K, V> onlyOnRight,
        Map<K, V> onBoth,
        Map<K, ValueDifference<V>> differences) {
      this.onlyOnLeft = unmodifiableMap(onlyOnLeft);

      implements MapDifference<K, V> {
    final Map<K, V> onlyOnLeft;
    final Map<K, V> onlyOnRight;
    final Map<K, V> onBoth;
    final Map<K, ValueDifference<V>> differences;

    MapDifferenceImpl(
        Map<K, V> onlyOnLeft,
        Map<K, V> onlyOnRight,
        Map<K, V> onBoth,
        Map<K, ValueDifference<V>> differences) {
      this.onlyOnLeft = unmodifiableMap(onlyOnLeft);

        // don't merge
    }

    @Override
    protected void mergeModel_Profiles(
            Model.Builder builder, Model target, Model source, boolean sourceDominant, Map<Object, Object> context) {
        Iterator<Profile> sourceIterator = source.getProfiles().iterator();
        builder.profiles(target.getProfiles().stream()