code: public Retryer<R> randomWait(long minimum, TimeUnit minUnit, long maximum, TimeUnit maxUnit) {
          return randomWait(checkNotNull(minUnit).toMillis(minimum), checkNotNull(maxUnit).toMillis(maximum));
      }
docs: Sets the strategy that sleeps a random amount of time before retrying
  
  @param minimum
  @param minUnit
  @param maximum
  @param maxUnit
  @return