public static String parseDate(String nTime) {
		try {
			String ret = "";
			SimpleDateFormat sdf = null;
			if (nTime.length() == 19) {
				sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
			} else if (nTime.length() == 16) {
				sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm");
			} else if (nTime.length() == 13) {
				sdf = new SimpleDateFormat("yyyy-MM-dd HH");
			} else if (nTime.length() == 10) {
				sdf = new SimpleDateFormat("yyyy-MM-dd");
			}
			long create = sdf.parse(nTime).getTime();
			Calendar now = Calendar.getInstance();
			long ms = 1000 * (now.get(Calendar.HOUR_OF_DAY) * 3600
					+ now.get(Calendar.MINUTE) * 60 + now.get(Calendar.SECOND));// 毫秒数
			long ms_now = now.getTimeInMillis();
			if (ms_now - create < ms) {
				ret = "today";
			} else if (ms_now - create < (ms + 24 * 3600 * 1000)) {
				ret = "yesterday";
			} else {
				ret = "before";
			}
			return ret;
		} catch (Exception e) {
			e.printStackTrace();
		}
		return "";
	}