code: public static long encode(int hi, int lo) {
          long h = ((long) hi) & 0xFFFF_FFFFL;
          long l = ((long) lo) & 0xFFFF_FFFFL;
          return (h << 32) + l;
      }
docs: Encodes hi and lo values into a long.
  
  @param hi the hi value
  @param lo the lo value
  @return the encoded value