* constructor uses a null {@code Comparator} to mean "natural ordering," whereas this factory
   * rejects null. Clean your code accordingly.
   *
   * @param comparator the comparator to use to sort the set
   * @return a new, empty {@code TreeSet}
   * @throws NullPointerException if {@code comparator} is null
   */
  public static <E extends @Nullable Object> TreeSet<E> newTreeSet(

        String groupId = model.getGroupId();
        if (groupId == null && model.getParent() != null) {
            groupId = model.getParent().getGroupId();
        }
        return groupId;
    }

    private String getVersion(Model model) {
        String version = model.getVersion();
        if (version == null && model.getParent() != null) {
            version = model.getParent().getVersion();
        }

                        prefix + prefix2 + "(groupId:artifactId)",
                        null,
                        "groupId of a plugin must be defined. ",
                        plugin);
            }

            if (plugin.getArtifactId() == null
                    || (plugin.getArtifactId() != null
                            && plugin.getArtifactId().trim().isEmpty())) {
                addViolation(

                MavenProject project = request.getProject();

                List<ModelProblem> modelProblems = null;
                Throwable error = null;

                if (project == null) {
                    project = new MavenProject();
                    project.setFile(pomFile != null ? pomFile.toFile() : null);

                    ModelBuildingListener listener =

    List<@Nullable String> list = newArrayList("a", null, "b", null, "a", null);
    assertEquals(2, Iterators.frequency(list.iterator(), "a"));
    assertEquals(1, Iterators.frequency(list.iterator(), "b"));
    assertEquals(0, Iterators.frequency(list.iterator(), "c"));
    assertEquals(0, Iterators.frequency(list.iterator(), 4.2));
    assertEquals(3, Iterators.frequency(list.iterator(), null));
  }

    @CheckForNull
    private Iterator<? extends Iterator<? extends T>> getTopMetaIterator() {
      while (topMetaIterator == null || !topMetaIterator.hasNext()) {
        if (metaIterators != null && !metaIterators.isEmpty()) {
          topMetaIterator = metaIterators.removeFirst();
        } else {
          return null;
        }
      }

   *
   * <p>It's acceptable for the underlying multimap to contain null keys, and even null values
   * provided that the function is capable of accepting null input. The transformed multimap might
   * contain null values, if the function sometimes gives a null result.
   *
   * <p>The returned multimap is not thread-safe or serializable, even if the underlying multimap

   *
   * @throws NullPointerException if any key or value in {@code map} is null
   */
  @SuppressWarnings("unchecked")
  public static <K, V> ImmutableSortedMap<K, V> copyOfSorted(SortedMap<K, ? extends V> map) {
    Comparator<? super K> comparator = map.comparator();
    if (comparator == null) {
      // If map has a null comparator, the keys should have a natural ordering,

	}

	toEncode := io.Reader(data)
	if data.Size() >= bigFileThreshold {
		// We use 2 buffers, so we always have a full buffer of input.
		pool := globalBytePoolCap.Load()
		bufA := pool.Get()
		bufB := pool.Get()
		defer pool.Put(bufA)
		defer pool.Put(bufB)

	// Empty fi.VersionID indicates that versioning is either
	// suspended or disabled on this bucket. RenameData will replace
	// the 'null' version. We add a free-version to track its tiered
	// content for asynchronous deletion.
	//
	// Note: RestoreObject and HealObject requests don't end up replacing the
	// null version and therefore don't require the free-version to track
	// anything