date转long 和long转date

import java.text.SimpleDateFormat; import java.util.Date; public class T { public static void main(String[] args) throws Exception { SimpleDateFormat sdf=new SimpleDateFormat("yyyy-MM-dd HH:mm:ss"); long timeStart=sdf.parse("2011-09-20 12:30:45").getTime(); System.out.println(timeStart); Date date = new Date(timeStart); System.out.println(sdf.format(date)); }