code: public final int getBeUint24() {
          if (position + 2 >= origin + limit) throw new IllegalArgumentException("limit excceed: "
                                                                                 + (position - origin + 2));
  
          byte[] buf = buffer;
          return ((0xff & buf[position++]) << 16) | ((0xff & buf[position++]) << 8) | (0xff & buf[position++]);
      }
docs: Return next 24-bit unsigned int from buffer. (big-endian)
  
  @see mysql-5.6.10/include/myisampack.h - mi_usint3korr