时间据当前时刻的方法

// 查询离最近的日期
	/**
	 * @param time 字符串类型
	 * @return timer 返回的时最近的时间
	 * */
		public static String lastTimeStr(String time) throws ParseException {
			String timer = "";
			if (time.equals("") || time == null) {
				//System.out.println("---日期为空--");
				return "emptyError";
			} else {
				timer = time.substring(0, 19);//精确到秒
				//System.out.println(timer);				
				DateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
				Date intime=df.parse(timer);
				Date now = new Date();		
				long diff = now.getTime() - intime.getTime();
				if (diff < 0) {
					System.out.println("录入日期有误，请检查数据");
					return "dateError";
				} else {
					long days = diff / (1000 * 60 * 60 * 24);
				
					long hours = (diff - days * (1000 * 60 * 60 * 24))/ (1000 * 60 * 60);
				
					long minutes = (diff - days * (1000 * 60 * 60 * 24) - hours* (1000 * 60 * 60))/ (1000 * 60);
					//System.out.println("you:" + minutes);
					if (days < 1) {
						if (hours < 1) {
							timer = minutes + "分钟以前";
						} else {
							timer = hours + "小时以前";
						}
					} else {
						timer = days + "天以前";
					}
				}
				return timer;
			}

		}