方法一:

System.out.println(System.currentTimeMillis());

 

 

方法二:    java.util.Date 工具类

Date date = new Date();
        System.out.println(date.getTime());

 

  

方法三:    java.util.Calendar 工具类

Calendar calendar = Calendar.getInstance();
        long time = calendar.getTimeInMillis();
        System.out.println(time);