final transient E element;

  SingletonImmutableSet(E element) {
    this.element = Preconditions.checkNotNull(element);
  }

  @Override
  public int size() {
    return 1;
  }

  @Override
  public boolean contains(@CheckForNull Object target) {
    return element.equals(target);
  }

  @Override
  public UnmodifiableIterator<E> iterator() {

    public abstract Builder<E> add(E element);

    @CanIgnoreReturnValue
    public Builder<E> add(E... elements) {
      checkNotNull(elements); // for GWT
      for (E element : elements) {
        add(checkNotNull(element));
      }
      return this;
    }

    @CanIgnoreReturnValue
    public Builder<E> addAll(Iterable<? extends E> elements) {
      checkNotNull(elements); // for GWT

                    List<Integer> columnKeys = Lists.newArrayList();
                    for (Object element : elements) {
                      @SuppressWarnings("unchecked")
                      Cell<String, Integer, Character> cell =
                          (Cell<String, Integer, Character>) element;
                      columnKeys.add(cell.getColumnKey());

  // Query Operations

  /**
   * Returns the number of occurrences of {@code element} in this multiset.
   *
   * @param element the element to look for
   * @return the nonnegative number of occurrences of the element
   */
  @Override
  public int count(@CheckForNull Object element) {
    AtomicInteger existingCounter = Maps.safeGet(countMap, element);
    return (existingCounter == null) ? 0 : existingCounter.get();
  }

     * {@code list.size()} if there is no such element.
     *
     * <p>Note that the return value will be {@code >= 0} if and only if there is an element of the
     * list that compares as equal to the key.
     *
     * <p>This is equivalent to the behavior of {@link java.util.Collections#binarySearch(List,

      for (int i = 0; i < 100; i++) {
        Element element = Element.values()[random.nextInt(range)];
        elements.add(element);
        queue.add(element);
      }
      Iterator<Element> queueIterator = queue.iterator();
      int remaining = queue.size();
      while (queueIterator.hasNext()) {
        Element element = queueIterator.next();
        remaining--;

  public void testHashCode_containingNull() {
    Collection<E> elements = getSampleElements(getNumElements() - 1);
    int expectedHashCode = 0;
    for (E element : elements) {
      expectedHashCode += ((element == null) ? 0 : element.hashCode());
    }

    elements.add(null);
    collection = getSubjectGenerator().create(elements.toArray());
    assertEquals(

    try {
      super.testNulls();
    } catch (AssertionFailedError e) {
      assertWithMessage("Method did not throw null pointer OR element not in graph exception.")
          .that(e)
          .hasCauseThat()
          .hasMessageThat()
          .contains(ERROR_ELEMENT_NOT_IN_GRAPH);
    }
  }

        elements[i] = entry.getElement();
        counts[i] = entry.getCount();
        i++;
      }
    }

    Object readResolve() {
      ImmutableMultiset.Builder<Object> builder =
          new ImmutableMultiset.Builder<Object>(elements.length);
      for (int i = 0; i < elements.length; i++) {
        builder.addCopies(elements[i], counts[i]);
      }

      Iterable<? extends E> elements) {
    checkNotNull(elements); // for GWT
    // Let ArrayList's sizing logic work, if possible
    return (elements instanceof Collection)
        ? new ArrayList<>((Collection<? extends E>) elements)
        : newArrayList(elements.iterator());
  }

  /**
   * Creates a <i>mutable</i> {@code ArrayList} instance containing the given elements; a very thin