public Date setYear(int localYear) {
   if (getYear() != localYear) {
     super.setYear(localYear);
     gregorianYear = FIELD_UNDEFINED;
   }
   return this;
 }
 public Date setEra(Era era) {
   if (getEra() != era) {
     super.setEra(era);
     gregorianYear = FIELD_UNDEFINED;
   }
   return this;
 }
 void setLocalEra(Era era) {
   super.setEra(era);
 }
 public Date addYear(int localYear) {
   super.addYear(localYear);
   gregorianYear += localYear;
   return this;
 }
 void setLocalYear(int year) {
   super.setYear(year);
 }