if (last == UNSET) {
            // we need to update the root link from table[]
            table[tableIndex] = getNext(entries[next]);
          } else {
            // we need to update the link from the chain
            entries[last] = swapNext(entries[last], getNext(entries[next]));
          }

          moveLastEntry(next);
          size--;
          modCount++;
          return oldValue;

   * wish to override {@link #lower} to forward to this implementation.
   */
  protected @Nullable E standardLower(@ParametricNullness E e) {
    return Iterators.getNext(headSet(e, false).descendingIterator(), null);
  }

  @Override
  public @Nullable E floor(@ParametricNullness E e) {
    return delegate().floor(e);
  }

  /**

        ReferenceEntry<K, V> first, ReferenceEntry<K, V> entry) {
      int newCount = count;
      ReferenceEntry<K, V> newFirst = entry.getNext();
      for (ReferenceEntry<K, V> e = first; e != entry; e = e.getNext()) {
        ReferenceEntry<K, V> next = copyEntry(e, newFirst);
        if (next != null) {
          newFirst = next;
        } else {
          removeCollectedEntry(e);

  /** Returns the hash prefix given the current mask. */
  static int getHashPrefix(int value, int mask) {
    return value & ~mask;
  }

  /** Returns the index, or 0 if the entry is "null". */
  static int getNext(int entry, int mask) {
    return entry & mask;
  }

  /** Returns a new value combining the prefix and suffix using the given mask. */
  static int maskCombine(int prefix, int suffix, int mask) {

  @Override
  public @Nullable Entry<K, V> firstEntry() {
    return Iterators.<@Nullable Entry<K, V>>getNext(entryIterator(), null);
  }

  @Override
  public @Nullable Entry<K, V> lastEntry() {
    return Iterators.<@Nullable Entry<K, V>>getNext(descendingEntryIterator(), null);
  }

  @Override
  public @Nullable Entry<K, V> pollFirstEntry() {

     * @return the new first entry for the table
     */
    @GuardedBy("this")
    @Nullable E removeFromChain(E first, E entry) {
      int newCount = count;
      E newFirst = entry.getNext();
      for (E e = first; e != entry; e = e.getNext()) {
        E next = copyEntry(e, newFirst);
        if (next != null) {
          newFirst = next;
        } else {
          newCount--;
        }
      }

  /** Returns the hash prefix given the current mask. */
  static int getHashPrefix(int value, int mask) {
    return value & ~mask;
  }

  /** Returns the index, or 0 if the entry is "null". */
  static int getNext(int entry, int mask) {
    return entry & mask;
  }

  /** Returns a new value combining the prefix and suffix using the given mask. */
  static int maskCombine(int prefix, int suffix, int mask) {

  @Override
  public @Nullable Entry<K, V> firstEntry() {
    return Iterators.<@Nullable Entry<K, V>>getNext(entryIterator(), null);
  }

  @Override
  public @Nullable Entry<K, V> lastEntry() {
    return Iterators.<@Nullable Entry<K, V>>getNext(descendingEntryIterator(), null);
  }

  @Override
  public @Nullable Entry<K, V> pollFirstEntry() {

      assertEquals(hashOne, entryOne.getHash());
      assertThat(entryOne.getNext()).isNull();
      assertSame(valueOne, copyOne.getValue());

      InternalEntry<Object, Object, ?> copyTwo = segment.copyForTesting(entryTwo, copyOne);
      assertSame(keyTwo, copyTwo.getKey());
      assertEquals(hashTwo, copyTwo.getHash());
      assertSame(copyOne, copyTwo.getNext());
      assertSame(valueTwo, copyTwo.getValue());
    }
  }

      assertEquals(hashOne, entryOne.getHash());
      assertThat(entryOne.getNext()).isNull();
      assertSame(valueOne, copyOne.getValue());

      InternalEntry<Object, Object, ?> copyTwo = segment.copyForTesting(entryTwo, copyOne);
      assertSame(keyTwo, copyTwo.getKey());
      assertEquals(hashTwo, copyTwo.getHash());
      assertSame(copyOne, copyTwo.getNext());
      assertSame(valueTwo, copyTwo.getValue());
    }
  }