据当前最近的时间，精确到秒

精确到秒

	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			
				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 % (1000 * 60 * 60 * 24)) / (1000 * 60 * 60);  
				    long minutes = (diff % (1000 * 60 * 60)) / (1000 * 60);  
				    long seconds = (diff % (1000 * 60)) / 1000;  	
					if (days < 1) {
						if (hours < 1) {
							
						if(minutes<1){
							timer = seconds + "秒以前";
						}else{
							timer = minutes + "分钟以前";
						}
						} else {
							timer = hours + "小时以前";
						}
					} else {
						timer = days + "天以前";
					}
				}
				return timer;
			}

		}