checkNotNull(sequence);
      return "";
    }

    @Override
    public String replaceFrom(CharSequence sequence, char replacement) {
      char[] array = new char[sequence.length()];
      Arrays.fill(array, replacement);
      return new String(array);
    }

    @Override
    public String replaceFrom(CharSequence sequence, CharSequence replacement) {

    }

    @Override
    @SuppressWarnings("nullness") // b/192354773 in our checker affects toArray declarations
    public <T extends @Nullable Object> T[] toArray(T[] array) {
      return standardToArray(array);
    }

    @Override
    public String toString() {
      return standardToString();
    }
  }

  /**

   */

  /**
   * Ensures that {@code index} specifies a valid <i>element</i> in an array, list or string of size
   * {@code size}. An element index may range from zero, inclusive, to {@code size}, exclusive.
   *
   * @param index a user-supplied index identifying an element of an array, list or string
   * @param size the size of that array, list or string
   * @return the value of {@code index}

  public void testForArrayLengthWithPositionBoundaryCases() {
    String[] array = {"foo", "bar"};
    assertFalse(Iterators.forArrayWithPosition(array, 2).hasNext());
    try {
      Iterators.forArrayWithPosition(array, -1);
      fail();
    } catch (IndexOutOfBoundsException expected) {
    }
    try {
      Iterators.forArrayWithPosition(array, 3);
      fail();
    } catch (IndexOutOfBoundsException expected) {

  }

  private static byte[] prepended(byte b, byte[] array) {
    byte[] out = new byte[array.length + 1];
    out[0] = b;
    System.arraycopy(array, 0, out, 1, array.length);
    return out;
  }

  @GwtIncompatible // java.nio.ByteBuffer
  private static byte[] toByteArray(int h) {
    return ByteBuffer.allocate(4).putInt(h).array();
  }

  public void testNewEnumSet_empty() {

      Iterable<? extends Entry<? extends K, ? extends V>> entries) {
    // "adding" type params to an array of a raw type should be safe as
    // long as no one can ever cast that same array instance back to a
    // raw type.
    @SuppressWarnings("unchecked")
    Entry<K, V>[] entryArray = (Entry[]) Iterables.toArray(entries, EMPTY_ENTRY_ARRAY);
    return fromEntries(comparator, sameComparator, entryArray, entryArray.length);
  }

        Set<String> fieldSet = (Set<String>) propMap.get(INDEX_ADMIN_ARRAY_FIELD_SET);
        if (fieldSet == null) {
            fieldSet = split(getIndexAdminArrayFields(), ",")
                    .get(stream -> stream.filter(StringUtil::isNotBlank).map(String::trim).collect(Collectors.toSet()));
            propMap.put(INDEX_ADMIN_ARRAY_FIELD_SET, fieldSet);
        }
        return fieldSet;
    }

        try {
            final FileChannel channel = in.getChannel();
            final ByteBuffer buffer = ByteBuffer.allocate(DEFAULT_BUF_SIZE);
            final byte[] buf = buffer.array();
            int len;
            int amount = 0;
            while ((len = ChannelUtil.read(channel, buffer, amount)) != -1) {
                out.write(buf, 0, len);
                buffer.clear();

      Iterable<? extends Entry<? extends K, ? extends V>> entries) {
    // "adding" type params to an array of a raw type should be safe as
    // long as no one can ever cast that same array instance back to a
    // raw type.
    @SuppressWarnings("unchecked")
    Entry<K, V>[] entryArray = (Entry[]) Iterables.toArray(entries, EMPTY_ENTRY_ARRAY);
    return fromEntries(comparator, sameComparator, entryArray, entryArray.length);
  }

    }

    @Override
    @SuppressWarnings("nullness") // b/192354773 in our checker affects toArray declarations
    public <T extends @Nullable Object> T[] toArray(T[] array) {
      synchronized (mutex) {
        return ObjectArrays.toArrayImpl(delegate(), array);
      }
    }

    @Override
    public boolean contains(@CheckForNull Object o) {
      synchronized (mutex) {