*
   * <p>This abstraction allows us to use single-instruction load and put when available, or fall
   * back on the slower approach of using Longs.fromBytes(byte...).
   */
  private interface LittleEndianBytes {
    long getLongLittleEndian(byte[] array, int offset);

    void putLongLittleEndian(byte[] array, int offset, long value);

    boolean usesFastPath();

    assertThrows(
        IllegalArgumentException.class, () -> Chars.fromByteArray(new byte[Chars.BYTES - 1]));
  }

  @GwtIncompatible // Chars.fromBytes
  public void testFromBytes() {
    assertThat(Chars.fromBytes((byte) 0x23, (byte) 0x45)).isEqualTo('\u2345');
    assertThat(Chars.fromBytes((byte) 0xFE, (byte) 0xDC)).isEqualTo('\uFEDC');
  }

  @GwtIncompatible // Chars.fromByteArray, Chars.toByteArray

   * immutability contract of {@code HashCode}. The array cannot be empty.
   *
   * @since 15.0 (since 12.0 in HashCodes)
   */
  public static HashCode fromBytes(byte[] bytes) {
    checkArgument(bytes.length >= 1, "A HashCode must contain at least 1 byte.");
    return fromBytesNoCopy(bytes.clone());
  }

  /**

    assertThrows(IllegalArgumentException.class, () -> Shorts.fromByteArray(new byte[] {0x01}));
  }

  @GwtIncompatible // Shorts.fromBytes
  public void testFromBytes() {
    assertThat(Shorts.fromBytes((byte) 0x23, (byte) 0x45)).isEqualTo((short) 0x2345);
    assertThat(Shorts.fromBytes((byte) 0xFE, (byte) 0xDC)).isEqualTo((short) 0xFEDC);
  }

  @GwtIncompatible // Shorts.fromByteArray, Shorts.toByteArray

      k1 ^= toUnsignedInt(input[off + i]) << shift;
    }
    h1 ^= mixK1(k1);
    return fmix(h1, len);
  }

  private static int getIntLittleEndian(byte[] input, int offset) {
    return Ints.fromBytes(input[offset + 3], input[offset + 2], input[offset + 1], input[offset]);
  }

  private static int mixK1(int k1) {
    k1 *= C1;
    k1 = Integer.rotateLeft(k1, 15);
    k1 *= C2;
    return k1;
  }

    return fromBytes(bytes[0], bytes[1]);
  }

  /**
   * Returns the {@code char} value whose byte representation is the given 2 bytes, in big-endian
   * order; equivalent to {@code Chars.fromByteArray(new byte[] {b1, b2})}.
   *
   * @since 7.0
   */
  @GwtIncompatible // doesn't work
  public static char fromBytes(byte b1, byte b2) {
    return (char) ((b1 << 8) | (b2 & 0xFF));

    return fromBytes(bytes[0], bytes[1]);
  }

  /**
   * Returns the {@code short} value whose byte representation is the given 2 bytes, in big-endian
   * order; equivalent to {@code Shorts.fromByteArray(new byte[] {b1, b2})}.
   *
   * @since 7.0
   */
  @GwtIncompatible // doesn't work
  public static short fromBytes(byte b1, byte b2) {

        IllegalArgumentException.class, () -> Ints.fromByteArray(new byte[Ints.BYTES - 1]));
  }

  public void testFromBytes() {
    assertThat(Ints.fromBytes((byte) 0x12, (byte) 0x13, (byte) 0x14, (byte) 0x15))
        .isEqualTo(0x12131415);
    assertThat(Ints.fromBytes((byte) 0xFF, (byte) 0xEE, (byte) 0xDD, (byte) 0xCC))
        .isEqualTo(0xFFEEDDCC);
  }

  public void testByteArrayRoundTrips() {

    return fromBytes(bytes[0], bytes[1]);
  }

  /**
   * Returns the {@code short} value whose byte representation is the given 2 bytes, in big-endian
   * order; equivalent to {@code Shorts.fromByteArray(new byte[] {b1, b2})}.
   *
   * @since 7.0
   */
  @GwtIncompatible // doesn't work
  public static short fromBytes(byte b1, byte b2) {

      k1 ^= toUnsignedInt(input[off + i]) << shift;
    }
    h1 ^= mixK1(k1);
    return fmix(h1, len);
  }

  private static int getIntLittleEndian(byte[] input, int offset) {
    return Ints.fromBytes(input[offset + 3], input[offset + 2], input[offset + 1], input[offset]);
  }

  private static int mixK1(int k1) {
    k1 *= C1;
    k1 = Integer.rotateLeft(k1, 15);
    k1 *= C2;
    return k1;
  }