code: public static long randomLong(final long min, final long max) {
  
          return Math.round(Math.random() * (max - min) + min);
      }
docs: Returns a natural long value between given minimum value and max value.
  
  @param min
  the minimum value to random.
  @param max
  the max value to random.
  @return a natural long value between given minimum value and max value.