code: private String getReadableTime()
      {
          long ns = getTimeNanos();
  
          if( ns < 50L * 1000 )
              return ns + " ns";
  
          if( ns < 50L * 1000 * 1000 )
              return (ns/1000)+" us";
  
          if( ns < 50L * 1000 * 1000 * 1000 )
              return (ns/(1000*1000))+" ms";
  
          return ns/NANOS_IN_SECOND + " s";
      }
docs: Returns a the time in something that is human-readable.
  
  @return A human-readable time string.