docs: public static final long readLong(byte[] array, int offset)
      {
          if (array.length < offset + 8)
          {
              throw new IllegalArgumentException("no room in array");
          }
          return
                  (((long)array[offset]<<56) & 0xff00000000000000L) +
                  (((long)array[offset + 1]<<48) & 0xff000000000000L)  +
                  (((long)array[offset + 2]<<40) & 0xff0000000000L)  +
                  (((long)array[offset + 3]<<32) & 0xff00000000L)  +
                  (((long)array[offset + 4]<<24) & 0xff000000L)  +
                  (((long)array[offset + 5]<<16) & 0xff0000L)  +
                  (((long)array[offset + 6]<<8) & 0xff00L)  +
                  ((long)array[offset + 7] & 0xff );
      }