long类型的时间转为n秒前n分钟前n小时前或者日期

package com.tai.use;

import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;

public class GuiYI
{
    /**
     * GuiYI 诡异的需求
     * 转为 n秒前   n分钟前   n小时前  日期
     * @param time
     * @param format  很长时间前显示的日期格式
     * @return
     */
        public static String dataLongToSNS(long time,String format){
            long now = System.currentTimeMillis();
            
            long diff = now -time;
            diff = diff/1000;// 秒
            
            if(diff<0){
                return dateLongToString(time,format);
            }
            
            if(diff<30){ // 30秒
                return "刚刚";
            }
            
            if(diff<60){
                return String.format("%s秒前", diff);
            }
            
            if(diff<3600){
                return String.format("%s分钟前", diff/60);
            }
            //获取今天凌晨时间
            long todayStart = getMoring(new Date()).getTime();
            
            if(time>=todayStart){// 今天
                return String.format("%s小时前", diff/3600);
            }
            
            if(time<todayStart && time >= todayStart-86400000){
                return "昨天 " + dateLongToString(time, "HH:mm");
            }
            
            return dateLongToString(time,format);
        }
        //获取今天凌晨的时间
        private static Date getMoring(Date date)
        {
            Calendar calendar  = Calendar.getInstance();
            calendar.setTime(date);
            calendar.set(Calendar.HOUR_OF_DAY, 0);
            calendar.set(Calendar.MINUTE, 0);
            calendar.set(Calendar.SECOND, 0);
            return calendar.getTime();
        }
        public static String dateLongToString(long time){
            return dateLongToString(time,null);
        }
        public static String dateLongToString(long time,String format){
            if(time<=0){
                return "Empty";
            }
            DateFormat format2 = new SimpleDateFormat(format);
            String dateString = format2.format(new Date(time));
            return dateString;
        }
        
        public static void main(String[] args)
        {
            System.out.println(dataLongToSNS(1400837178603L,"yyyy-MM-dd HH:mm:ss"));
        }
}