code: public static long readLong(ArrayView source, int position) {
          return (long) (source.get(position) & 0xFF) << 56
                  | (long) (source.get(position + 1) & 0xFF) << 48
                  | (long) (source.get(position + 2) & 0xFF) << 40
                  | (long) (source.get(position + 3) & 0xFF) << 32
                  | (long) (source.get(position + 4) & 0xFF) << 24
                  | (source.get(position + 5) & 0xFF) << 16
                  | (source.get(position + 6) & 0xFF) << 8
                  | (source.get(position + 7) & 0xFF);
      }
docs: Reads a 64-bit long from the given ArrayView starting at the given position.
  
  @param source   The ArrayView to read from.
  @param position The position in the ArrayView to start reading at.
  @return The read number.