return (javaUtilOptional == null) ? null : fromNullable(javaUtilOptional.orElse(null));
  }

  /**
   * Returns the equivalent {@code java.util.Optional} value to the given {@code
   * com.google.common.base.Optional}, or {@code null} if the argument is null.
   *
   * <p>If {@code googleOptional} is known to be non-null, use {@code googleOptional.toJavaUtil()}
   * instead.
   *

    Set<CombinedInterface> getSetProp() { return null; }

    Map<CombinedInterface, JavaClassWithParameterizedTypes> getMapProp() { return null; }

    List<?> getWildcardProp() { return null; }

    List<? extends CombinedInterface> getUpperBoundProp() { return null; }

    List<? super CombinedInterface> getLowerBoundProp() { return null; }

        return format(null, paths);
    }

    /**
     * Implementation shared with {@link Modular}.
     */
    final String[] format(String moduleName, Iterable<? extends Path> paths) {
        if (option == null) {
            throw new IllegalStateException("No option is associated to this path type.");
        }
        String prefix = (moduleName == null) ? "" : (moduleName + '=');

    targets:
      include:
      - '*'
  abbr: null
  attr_list: null
  footnotes: null
  md_in_html: null
  tables: null
  toc:
    permalink: true
  pymdownx.betterem: null
  pymdownx.caret: null
  pymdownx.highlight:
    line_spans: __span
  pymdownx.inlinehilite: null
  pymdownx.keys: null
  pymdownx.mark: null
  pymdownx.superfences:
    custom_fences:
    - name: mermaid

    if (entry != null && entry.key == key) {
      return entry.value;
    }
    entry = cacheEntry2;
    if (entry != null && entry.key == key) {
      // Promote second cache entry to first so the access pattern
      // [K1, K2, K1, K3, K1, K4...] still hits the cache half the time.
      addToCache(entry);
      return entry.value;
    }
    return null;
  }

  @Override
  void clearCache() {
    super.clearCache();

    Predicate<@Nullable Integer> isNull = Predicates.equalTo(null);
    assertTrue(isNull.apply(null));
    assertFalse(isNull.apply(1));
  }

  public void testIsEqualToNull_equality() {
    new EqualsTester()
        .addEqualityGroup(
            Predicates.<@Nullable Integer>equalTo(null),
            Predicates.<@Nullable Integer>equalTo(null))
        .addEqualityGroup(Predicates.equalTo(1))

        HttpUrl link = response.request().url().resolve(href);
        if (link == null) continue; // URL is either invalid or its scheme isn't http/https.
        HttpUrl linkWithoutFragment = link.newBuilder().fragment(null).build();
        if (!queue.offer(linkWithoutFragment)) break; // Queue is full.
      }
    }
  }

  public static void main(String[] args) throws IOException {

  private val key: String

  /** Non-null for client web sockets. These can be canceled. */
  internal var call: Call? = null

  /** This task processes the outgoing queues. Call [runWriter] to after enqueueing. */
  private var writerTask: Task? = null

  /** Null until this web socket is connected. Only accessed by the reader thread. */
  private var reader: WebSocketReader? = null

        // v1-->v2
        graph.addEdge(v1, v2, new MetadataGraphEdge("1.1", true, null, null, 2, 1));
        graph.addEdge(v1, v2, new MetadataGraphEdge("1.2", true, null, null, 2, 2));

        // v1-->v3
        graph.addEdge(v1, v3, new MetadataGraphEdge("1.1", true, null, null, 2, 1));
        graph.addEdge(v1, v3, new MetadataGraphEdge("1.2", true, null, null, 4, 2));

        // v3-->v4

    assertNull("getOrDefault(absent, null) should return null", getMap().getOrDefault(k3(), null));
  }

  @MapFeature.Require(ALLOWS_NULL_KEY_QUERIES)
  public void testGetOrDefault_absentNull() {
    assertEquals(
        "getOrDefault(null, def) should return the default value",
        v3(),
        getMap().getOrDefault(null, v3()));
  }

  @MapFeature.Require(absent = ALLOWS_NULL_KEY_QUERIES)