}

    @Override
    public Set<E> create(Object... elements) {
      Object[] duplicated = new Object[elements.length * 2];
      for (int i = 0; i < elements.length; i++) {
        duplicated[i] = elements[i];
        duplicated[i + elements.length] = elements[i];
      }
      return ((Multiset<E>) gen.create(duplicated)).elementSet();
    }

    @Override
    public E[] createArray(int length) {

    return Spliterators.spliterator(elements, SPLITERATOR_CHARACTERISTICS);
  }

  @Override
  Object[] internalArray() {
    return elements;
  }

  @Override
  int internalArrayStart() {
    return 0;
  }

  @Override
  int internalArrayEnd() {
    return elements.length;
  }

  @Override
  int copyIntoArray(@Nullable Object[] dst, int offset) {
    arraycopy(elements, 0, dst, offset, elements.length);

            UpgradeContext context, Document pomDocument) {
        Element root = pomDocument.root();

        // Extract direct values
        String groupId = root.childTextTrimmed(MavenPomElements.Elements.GROUP_ID);
        String artifactId = root.childTextTrimmed(MavenPomElements.Elements.ARTIFACT_ID);
        String version = root.childTextTrimmed(MavenPomElements.Elements.VERSION);

   * inserted into the multiset must implement the {@code Comparable} interface. Furthermore, all
   * such elements must be <i>mutually comparable</i>: {@code e1.compareTo(e2)} must not throw a
   * {@code ClassCastException} for any elements {@code e1} and {@code e2} in the multiset. If the

    return new Strings();
  }

  @Override
  public Multiset<String> create(Object... elements) {
    String[] array = new String[elements.length];
    int i = 0;
    for (Object e : elements) {
      array[i++] = (String) e;
    }
    return create(array);
  }

  protected abstract Multiset<String> create(String[] elements);

  @Override
  public String[] createArray(int length) {
    return new String[length];

            + " even if some elements are null.",
        getSet().equals(MinimalSet.from(elements)));
  }

  @CollectionSize.Require(absent = CollectionSize.ZERO)
  public void testEquals_otherContainsNull() {
    Collection<E> elements = getSampleElements(getNumElements() - 1);
    elements.add(null);
    Set<E> other = MinimalSet.from(elements);

    assertFalse(

            + " even if some elements are null.",
        getSet().equals(MinimalSet.from(elements)));
  }

  @CollectionSize.Require(absent = CollectionSize.ZERO)
  public void testEquals_otherContainsNull() {
    Collection<E> elements = getSampleElements(getNumElements() - 1);
    elements.add(null);
    Set<E> other = MinimalSet.from(elements);

    assertFalse(

     * any of the algorithm name is not supported. The returned collection has equal count of elements as passed in
     * collection of names, and if names contains duplicated elements, the returned list of algorithms will have
     * duplicates as well.
     *
     * @throws ChecksumAlgorithmServiceException if any asked algorithm name is not supported.

 * elements FIFO (first-in-first-out). The head of the queue is that element that has been
 * on the queue the longest time. The tail of the queue is that element that has been on
 * the queue the shortest time. New elements are inserted at the tail of the queue, and the queue
 * retrieval operations obtain elements at the head of the queue.
 *

        this.parent = parent
    }

    protected Element createNode(Object name) {
        Element element = document.createElement(name as String)
        if (getCurrent() == null) {
            elements << element
            parent?.appendChild(element)
        }
        return element
    }

    protected Element createNode(Object name, Map attributes) {
        Element element = createNode(name)
        attributes.each {key, value ->