Get the number of days between dates, get the Chinese date, get the date of the next Monday of the date, get the working day, get the rest day

/** *  Gets the number of days between dates  * @param d1 * @param d2 * @return */
	public int getDaysBetween(java.util.Calendar d1, java.util.Calendar d2) {
    
		if (d1.after(d2)) {
    
			java.util.Calendar swap = d1;
			d1 = d2;
			d2 = swap;
		}
		int days = d2.get(java.util.Calendar.DAY_OF_YEAR)
				- d1.get(java.util.Calendar.DAY_OF_YEAR);
		int y2 = d2.get(java.util.Calendar.YEAR);
		if (d1.get(java.util.Calendar.YEAR) != y2) {
    
			d1 = (java.util.Calendar) d1.clone();
			do {
    
				days += d1.getActualMaximum(java.util.Calendar.DAY_OF_YEAR);
				d1.add(java.util.Calendar.YEAR, 1);
			} while (d1.get(java.util.Calendar.YEAR) != y2);
		}
		return days;
	}

	/** *  Get working days  * @param d1 * @param d2 * @return */
	public int getWorkingDay(java.util.Calendar d1, java.util.Calendar d2) {
    
		int result = -1;
		if (d1.after(d2)) {
    
			java.util.Calendar swap = d1;
			d1 = d2;
			d2 = swap;
		}
		int charge_start_date = 0;//  The date offset of the start date 
		int charge_end_date = 0;//  The date offset of the end date 
		//  The date is not in the same date 
		int stmp;
		int etmp;
		stmp = 7 - d1.get(Calendar.DAY_OF_WEEK);
		etmp = 7 - d2.get(Calendar.DAY_OF_WEEK);
		if (stmp != 0 && stmp != 6) {
    //  When the start date is Saturday and Sunday, the offset is 0
			charge_start_date = stmp - 1;
		}
		if (etmp != 0 && etmp != 6) {
    //  When the end date is Saturday and Sunday, the offset is 0
			charge_end_date = etmp - 1;
		}
		// }
		result = (getDaysBetween(this.getNextMonday(d1), this.getNextMonday(d2)) / 7)
				* 5 + charge_start_date - charge_end_date;
		return result;
	}

	/** *  Get Chinese date  * @param date * @return */
	public String getChineseWeek(Calendar date) {
    
		final String dayNames[] = {
     " Sunday ", " Monday ", " Tuesday ", " Wednesday ", " Thursday ", " Friday ", " Saturday " };
		int dayOfWeek = date.get(Calendar.DAY_OF_WEEK); 
		return dayNames[dayOfWeek - 1];
	}

	/** *  Get the date of the next Monday of the date  * @param date * @return */
	public Calendar getNextMonday(Calendar date) {
    
		Calendar result = null;
		result = date;
		do {
    
			result = (Calendar) result.clone();
			result.add(Calendar.DATE, 1);
		} while (result.get(Calendar.DAY_OF_WEEK) != 2);
		return result;
	}

	/** *  Get rest days  * @param d1 * @param d2 * @return */
	public int getHolidays(Calendar d1, Calendar d2) {
    
		return this.getDaysBetween(d1, d2) - this.getWorkingDay(d1, d2);
	}