code: public void setInto(ReadWritablePeriod duration, Object object, Chronology chrono) {
          duration.setPeriod((Period) null);
      }
docs: Sets the given ReadWritableDuration to zero milliseconds.
  
  @param duration duration to get modified
  @param object  the object to convert, which is null
  @param chrono  the chronology to use
  @throws NullPointerException if the duration is null