/** Private constructor for built-in DiscreteDomains supporting fast offset. */
  private DiscreteDomain(boolean supportsFastOffset) {
    this.supportsFastOffset = supportsFastOffset;
  }

  /**
   * Returns, conceptually, "origin + distance", or equivalently, the result of calling {@link
   * #next} on {@code origin} {@code distance} times.
   */
  C offset(C origin, long distance) {
    C current = origin;

    private final transient @Nullable Object[] alternatingKeysAndValues;
    private final transient int offset;
    private final transient int size;

    KeysOrValuesAsList(@Nullable Object[] alternatingKeysAndValues, int offset, int size) {
      this.alternatingKeysAndValues = alternatingKeysAndValues;
      this.offset = offset;
      this.size = size;
    }

    @Override
    public Object get(int index) {

    return new SubList(fromIndex, toIndex - fromIndex);
  }

  class SubList extends ImmutableList<E> {
    final transient int offset;
    final transient int length;

    SubList(int offset, int length) {
      this.offset = offset;
      this.length = length;
    }

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

    @Override

    private static final long HEAD_OFFSET;

    /**
     * A special instance of {@link RunnableExecutorPair} that is used as a sentinel value for the
     * bottom of the stack.
     */
    private static final RunnableExecutorPair NULL_PAIR = new RunnableExecutorPair(null, null);

    static {
      try {
        UNSAFE = getUnsafe();

  @GwtIncompatible // not present in emulated superclass
  @Override
  int copyIntoArray(@Nullable Object[] dst, int offset) {
    for (Multiset.Entry<E> entry : entrySet()) {
      Arrays.fill(dst, offset, offset + entry.getCount(), entry.getElement());
      offset += entry.getCount();
    }
    return offset;
  }

  @Override
  public boolean equals(@CheckForNull Object object) {

    assertThat(encoding.encode(decoded.getBytes(UTF_8))).isEqualTo(encoded);
  }

  private static void testEncodesWithOffset(
      BaseEncoding encoding, String decoded, int offset, int len, String encoded) {
    assertThat(encoding.encode(decoded.getBytes(UTF_8), offset, len)).isEqualTo(encoded);
  }

  private static void testDecodes(BaseEncoding encoding, String encoded, String decoded) {
    assertThat(encoding.canDecode(encoded)).isTrue();

    byte[] expected = newPreFilledByteArray(offset, expectRead);

    ByteSource source = new TestByteSource(newPreFilledByteArray(input));
    ByteSource slice = source.slice(offset, length);

    assertArrayEquals(expected, slice.read());
  }

  public void testCopyToStream_doesNotCloseThatStream() throws IOException {

          private final ByteArrayOutputStream out = new ByteArrayOutputStream();

          @Override
          public boolean processBytes(byte[] buffer, int offset, int length) throws IOException {
            if (length >= 0) {
              out.write(buffer, offset, length);
            }
            return true;
          }

          @Override
          public byte[] getResult() {

          }
        }
        int minOffset = alphabet.bytesPerChunk * 8 - charsProcessed * alphabet.bitsPerChar;
        for (int offset = (alphabet.bytesPerChunk - 1) * 8; offset >= minOffset; offset -= 8) {
          target[bytesWritten++] = (byte) ((chunk >>> offset) & 0xFF);
        }
      }
      return bytesWritten;
    }

    @Override
    @J2ktIncompatible

    assertThat(encoding.encode(decoded.getBytes(UTF_8))).isEqualTo(encoded);
  }

  private static void testEncodesWithOffset(
      BaseEncoding encoding, String decoded, int offset, int len, String encoded) {
    assertThat(encoding.encode(decoded.getBytes(UTF_8), offset, len)).isEqualTo(encoded);
  }

  private static void testDecodes(BaseEncoding encoding, String encoded, String decoded) {
    assertThat(encoding.canDecode(encoded)).isTrue();