docs: public byte byteAt(int i) {
  
      if (i < 0) {
        throw new IndexOutOfBoundsException("i < 0, " + i);
      }
  
      if (i >= length) {
        throw new IndexOutOfBoundsException("i >= length, " + i + " >= " + length);
      }
  
      return data[offset + i];
    }