MakkahCalendar.java

/*
	Makkah Calendar
	http://www.makkahcalendar.org/en/hijriCalendar.php

	Usage: String today = MakkahCalendar.getSimpleDate(null);
*/
import java.util.Calendar;  

public final class MakkahCalendar {

	public final static String[] WEEKDAYS = { 0, "Ahad", "Ithnain", "Thulatha", "Arba'a", "Khamsa", "Jumu'ah", "Sabt" };
	public final static String[] MONTHS = { 0, "Muharram", "Safar", "Rabi'ul awwal", "Rabi'ul akhir",
		"Jumadal ula", "Jumadal akhira", "Rajab", "Sha'ban", "Ramadhan", "Shawwal", "Dhul qa'ada", "Dhul hijja" };

	private final static int START_YEAR = 2009; //1 muharram 1431 = 18 dec 2009
	private final static int START_MONTH = Calendar.DECEMBER;
	private final static int START_DAY = 18;
	private final static int START_HIJRIYEAR = 1431;

	private final static int[] data = {
		30,29,30,30,29,30,29,29,30,29,29,30, //1431
		30,29,30,30,30,29,30,29,29,30,29,30, //1432
		29,29,30,30,30,29,30,30,29,29,30,29, //1433
		29,30,29,30,30,29,30,30,29,30,29,30, //1434
		29,29,30,29,30,30,29,30,29,30,30,29  //1435
	};

	public static int[] getDate(Calendar cal) {
		//get startdate calendar
		Calendar calS = Calendar.getInstance();
		calS.clear();
		calS.set(START_YEAR, START_MONTH, START_DAY);

		//today
		if (cal == null) cal = Calendar.getInstance();
		int weekday = cal.get(Calendar.DAY_OF_WEEK);

		//total days since startdate
		long diff = cal.getTimeInMillis() - calS.getTimeInMillis();
		int elapse = (int)(diff / (24 * 60 * 60 * 1000)); //includes start day
		if (elapse < 0) return fallback(cal);

		int year = START_HIJRIYEAR;
		int month = 1;
		int day = 1;
		int total = 0;
		boolean inRange = false;
		for (int i=0; i<data.length; i++) {
			if (elapse < total+data[i]) {
				day = elapse - total;
				inRange = true;
				break;
			}
			total += data[i];
			month++;
			if (month > 12) { month = 1; year++; }
		}

		if (!inRange) return fallback(cal);

		return new int[]{ weekday, day, month, year };
	}

	public static int[] fallback(Calendar cal) {
		return null; //or fallback to other methods
	}

	public static String getSimpleDate(Calendar cal) {
		int[] dt = getDate(cal);
		if (dt == null) return "Date not in range";
		return WEEKDAYS[dt[0]] + ", " + dt[1] + " " + MONTHS[dt[2]] + " " + dt[3] + "H";
	}
}