java 从mysql中的integer转成时间类型

Date nedate = new Date();
DateFormat dateformat = new SimpleDateFormat("yyy-MM-dd HH:mm:ss");
int seconds=1481194381;
long millions=new Long(seconds)*1000;
nedate.setTime(millions);
System.out.println(dateformat.format(nedate));

Date date=new Date();
int seconds=popSsuSku.getFirstOnlineTime();
long millions=new Long(seconds)*1000;
date.setTime(millions);
DateUtil.getDateFormat(date);//首次上架时间