code: public MachineTime<TimeUnit> getSimpleDuration() {
  
          Moment tsp = this.getTemporalOfOpenEnd();
          boolean max = (tsp == null);
  
          if (max) { // max reached
              tsp = this.getEnd().getTemporal();
          }
  
          MachineTime<TimeUnit> result =
              MachineTime.ON_POSIX_SCALE.between(
                  this.getTemporalOfClosedStart(),
                  tsp);
  
          if (max) {
              return result.plus(1, TimeUnit.NANOSECONDS);
          }
  
          return result;
  
      }
docs: /*[deutsch]
  <p>Liefert die L&auml;nge dieses Intervalls auf der POSIX-Skala. </p>
  
  @return  machine time duration on POSIX-scale
  @throws  UnsupportedOperationException if this interval is infinite
  @since   2.0
  @see     #getRealDuration()