node.thread = null; // mark as 'deleted'
    restart:
    while (true) {
      Waiter pred = null;
      Waiter curr = waiters;
      if (curr == Waiter.TOMBSTONE) {
        return; // give up if someone is calling complete
      }
      Waiter succ;
      while (curr != null) {
        succ = curr.next;
        if (curr.thread != null) { // we aren't unlinking this node, update pred.

   * 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(

    override val element: KtUserType,
    val shortenedRef: String? = null,
    override val nameToImport: FqName? = null,
    override val importAllInParent: Boolean = false,
) : ElementToShorten()

private class ShortenQualifier(
    override val element: KtDotQualifiedExpression,
    val shortenedRef: String? = null,
    override val nameToImport: FqName? = null,
    override val importAllInParent: Boolean = false

                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 =

        if (psiElement !is KtExpression) return null
        if (firElement !is FirResolvedQualifier) return null

        val call = psiElement.getPossiblyQualifiedCallExpression() ?: return null
        if (call.typeArgumentList == null || call.valueArgumentList != null) return null

        val parentReferenceExpression = psiElement.parent as? KtDoubleColonExpression ?: return null

    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;
        }
      }

	}

	type QueryResetNullValue struct {
		ID      int
		Name    string     `gorm:"default:NULL"`
		Flag    bool       `gorm:"default:NULL"`
		Number1 int64      `gorm:"default:NULL"`
		Number2 uint64     `gorm:"default:NULL"`
		Number3 float64    `gorm:"default:NULL"`
		Now     *time.Time `gorm:"defalut:NULL"`
		Item1Id string
		Item1   *QueryResetItem `gorm:"references:ID"`
		Item2Id string