public static void putAt(Date self,int field,int value){
  Calendar cal=Calendar.getInstance();
  cal.setTime(self);
  putAt(cal,field,value);
  self.setTime(cal.getTimeInMillis());
}

public static void putAt ( Date self , int field , int value ) { Calendar cal = Calendar . getInstance ( ) ; cal . setTime ( self ) ; putAt ( cal , field , value ) ; self . setTime ( cal . getTimeInMillis ( ) ) ; }
support the subscript operator for mutating a date .
