private final transient int size;

  /*
   * We have some considerable complexity in these create methods because of
   * Builder.buildKeepingLast(). The same Builder might be called with buildKeepingLast() and then
   * buildOrThrow(), or vice versa. So in particular, if we modify alternatingKeysAndValues to
   * eliminate duplicate keys (for buildKeepingLast()) then we have to ensure that a later call to

   * compilation purposes.
   */
  enum Strength {
    /*
     * TODO(kevinb): If we strongly reference the value and aren't loading, we needn't wrap the
     * value. This could save ~8 bytes per entry.
     */

    STRONG {
      @Override
      Equivalence<Object> defaultEquivalence() {
        return Equivalence.equals();
      }
    },

    SOFT {
      @Override

    if (elements instanceof ImmutableCollection) {
      /*
       * TODO: When given an ImmutableList that's a sublist, copy the referenced
       * portion of the array into a new array to save space?
       */
      @SuppressWarnings("unchecked") // all supported methods are covariant
      ImmutableCollection<E> list = (ImmutableCollection<E>) elements;
      return list.asList();
    }

          // Inline the Comparator implementation rather than transforming with a Function
          // to save code size.
          Arrays.sort(
              entryArray,
              0,
              size,
              (e1, e2) -> {
                // requireNonNull is safe because the first `size` elements have been filled in.
                requireNonNull(e1);
                requireNonNull(e2);

          // Inline the Comparator implementation rather than transforming with a Function
          // to save code size.
          Arrays.sort(
              entryArray,
              0,
              size,
              (e1, e2) -> {
                // requireNonNull is safe because the first `size` elements have been filled in.
                requireNonNull(e1);
                requireNonNull(e2);

   * filters to be compatible, they must:
   *
   * <ul>
   *   <li>not be the same instance
   *   <li>have the same number of hash functions
   *   <li>have the same bit size
   *   <li>have the same strategy
   *   <li>have equal funnels
   * </ul>
   *
   * @param that The Bloom filter to check for compatibility.
   * @since 15.0
   */

 * second invocation, so implementors have made various choices, including:
 *
 * <ul>
 *   <li>returning the same iterator again
 *   <li>throwing an exception of some kind
 *   <li>or the usual, <i>robust</i> behavior, which all known {@link Collection} implementations
 *       have, of returning a new, independent iterator
 * </ul>
 *

   * first permutation will be in ascending order, and the last will be in descending order.
   *
   * <p>Duplicate elements are considered equal. For example, the list [1, 1] will have only one
   * permutation, instead of two. This is why the elements have to implement {@link Comparable}.
   *
   * <p>An empty iterable has only one permutation, which is an empty list.
   *

      switch (balanceFactor()) {
        case -2:
          // requireNonNull is safe because right must exist in order to get a negative factor.
          requireNonNull(right);
          if (right.balanceFactor() > 0) {
            right = right.rotateRight();
          }
          return rotateLeft();
        case 2:
          // requireNonNull is safe because left must exist in order to get a positive factor.

        /*
         * requireNonNull is safe because the callers promise to put non-null objects in the first
         * `length` array elements.
         */
        @SuppressWarnings("unchecked") // our callers put only E instances into the array
        E onlyElement = (E) requireNonNull(elements[0]);
        return of(onlyElement);
      default:
        /*