code: public int getDayOfYear() {
  
          int doy = this.iso.get(PlainDate.DAY_OF_YEAR);
  
          if (this.iso.getYear() < 1941) {
              if (this.iso.getMonth() >= 4) {
                  doy -= (this.iso.isLeapYear() ? 91 : 90);
              } else {
                  doy += 275; // 91 + 92 + 92
              }
          }
  
          return doy;
  
      }
docs: /*[deutsch]
  <p>Liefert den Tag des Jahres. </p>
  
  @return  int
  @since   3.19/4.15