}

    @Override
    public Hasher putBytes(ByteBuffer bytes) {
      stream.write(bytes);
      return this;
    }

    @Override
    public HashCode hash() {
      return hashBytes(stream.byteArray(), 0, stream.length());
    }
  }

  // Just to access the byte[] without introducing an unnecessary copy
  private static final class ExposedByteArrayOutputStream extends ByteArrayOutputStream {