ThaiBuddhistDate(LocalDate isoDate){
  Objects.requireNonNull(isoDate,"isoDate");
  this.isoDate=isoDate;
}

ThaiBuddhistDate ( LocalDate isoDate ) { Objects . requireNonNull ( isoDate , "isoDate" ) ; this . isoDate = isoDate ; }
creates an instance from an iso date .
