* (And even if annotations on local variables were permitted as an optional hint, no annotation
   * would be the right tool for the job here: {@code @Nullable} is the annotation that we're trying
   * to get rid of, and {@code @NonNull} would be wrong for our use case for the same reason as
   * {@code requireNonNull}: Our use case is the one in which {@code T} has parametric nullness—and
   * thus its value may be legitimately {@code null}.)
   */

        requireNonNull(readers, "readers");
        // skip possible null entries
        this.readers = Collections.unmodifiableList(
                new ArrayList<>(readers.stream().filter(Objects::nonNull).collect(Collectors.toList())));
        Key key = new Key(this.readers);
        this.repository = new WorkspaceRepository(key.getContentType(), key);
    }

    public List<WorkspaceReader> getReaders() {

    // TODO(lowasser): consider an implementation that can support SUBSIZED
    boolean isParallel = false;
    int characteristics = Spliterator.ORDERED | Spliterator.SIZED | Spliterator.NONNULL;
    long estimatedSize = 0L;
    ImmutableList.Builder<Spliterator<? extends T>> splitrsBuilder =
        new ImmutableList.Builder<>(streams.length);
    for (Stream<? extends T> stream : streams) {

    // TODO(lowasser): consider an implementation that can support SUBSIZED
    boolean isParallel = false;
    int characteristics = Spliterator.ORDERED | Spliterator.SIZED | Spliterator.NONNULL;
    long estimatedSize = 0L;
    ImmutableList.Builder<Spliterator<? extends T>> splitrsBuilder =
        new ImmutableList.Builder<>(streams.length);
    for (Stream<? extends T> stream : streams) {

    }

    @SuppressWarnings("nullness") // TODO: b/423853632 - Remove after checker is fixed.
    @Override
    public @Nullable V merge(
        K key,
        @NonNull V value,
        BiFunction<? super @NonNull V, ? super @NonNull V, ? extends @Nullable V>
            remappingFunction) {
      synchronized (mutex) {
        return delegate().merge(key, value, remappingFunction);
      }
    }

            MavenExecutionRequest request, ProjectBuildingException exception) {
        return exception.getResults().stream()
                .map(ProjectBuildingResult::getProject)
                .filter(Objects::nonNull)
                .filter(project -> request.getPom().equals(project.getFile()))
                .findFirst()
                .map(requestPomProject -> {

    return new CellSet();
  }

  abstract Iterator<Table.Cell<R, C, V>> cellIterator();

  Spliterator<Table.Cell<R, C, V>> cellSpliterator() {
    return Spliterators.spliterator(cellSet(), Spliterator.NONNULL | Spliterator.DISTINCT);
  }

  @WeakOuter
  private final class CellSet extends AbstractSet<Cell<R, C, V>> {
    @Override
    public boolean contains(@Nullable Object o) {
      if (o instanceof Cell) {

      throw new UnsupportedOperationException();
    }

    @Override
    public @Nullable V merge(
        K key,
        @NonNull V value,
        BiFunction<? super @NonNull V, ? super @NonNull V, ? extends @Nullable V> function) {
      throw new UnsupportedOperationException();
    }

    @Override
    public BiMap<V, K> inverse() {

      int index = e.ordinal();
      return index < enumConstants.length && enumConstants[index] == e;
    }
    return false;
  }

  /**
   * Returns {@code element} cast to {@code E}, if it actually is a nonnull E. Otherwise, throws
   * either a NullPointerException or a ClassCastException as appropriate.
   */
  private void checkIsE(Object element) {
    checkNotNull(element);
    if (!isActuallyE(element)) {

        List<Dependency> deps = new ArrayList<>(result.getDependencies().keySet());
        List<Dependency> deps2 = result.getNodes().stream()
                .map(Node::getDependency)
                .filter(Objects::nonNull)
                .collect(Collectors.toList());
        assertEquals(deps, deps2);
        for (Dependency dep : deps2) {
            dep.getVersion();
        }
    }