直接看到代码:

public static String toStringL(Long time,String pattern) {
		if (time.longValue() > 0L) {
			if (time.toString().length() == 10) {
				time = Long.valueOf(time.longValue() * 1000L);
			}
			Date date = new Date(time.longValue());
			String str = toString(date,pattern);
			return str;
		}
		return "";
	}

public static String toString(Date date,String pattern) {
		if (date == null) {
			date = new Date();
		}
		if (pattern == null) {
			pattern = "yyyy-MM-dd";
		}
		String dateString = "";
		SimpleDateFormat sdf = new SimpleDateFormat(pattern);
		try {
			dateString = sdf.format(date);
		} catch (Exception ex) {
			ex.printStackTrace();
		}
		return dateString;
	}