protected void gregorianToHijri(Calendar calendar, int diff) {
    	different = diff;
    	int y = calendar.get(YEAR);
    	int m = calendar.get(MONTH);
    	int d = calendar.get(DATE);
		
		int[] date = greToIsl(y, m, d, diff);
		
		fields[ERA] = AH;
		fields[YEAR] = date[2];
		fields[MONTH] = date[1]+1;
		fields[DAY_OF_MONTH] = date[0];
		fields[DAY_OF_WEEK] = calendar.get(DAY_OF_WEEK);
	}