public static String ms2Time(long ms) {
		long day = ms / DD;
		long hour = (ms - day * DD) / HH;
		long minute = (ms - day * DD - hour * HH) / MI;
		long second = (ms - day * DD - hour * HH - minute * MI) / SS;

		String strDay = day < CONSTANT_10 ? "0" + day : "" + day;
		String strHour = hour < CONSTANT_10 ? "0" + hour : "" + hour;
		String strMinute = minute < CONSTANT_10 ? "0" + minute : "" + minute;
		String strSecond = second < CONSTANT_10 ? "0" + second : "" + second;
		strDay = (StringUtils.equals(strDay, "00")) ? "" : strDay + ":";
		return strDay + strHour + ":" + strMinute + ":" + strSecond;
	}
Convert millisecond to DD:HH:MM:SS style.

@param ms	Millisecond
@return DD:HH:MM:SS formatted string
ngrinder-core/src/main/java/org/ngrinder/common/util/DateUtils.java