java 获取当前时间的三种方法
https://blog.csdn.net/c851204293/article/details/91801973

1.通过Util包中的Date获取

Date date = new Date();SimpleDateFormat dateFormat= new SimpleDateFormat("yyyy-MM-dd :hh:mm:ss");System.out.println(dateFormat.format(date));

2.通过Util包的Calendar 获取

Calendar calendar= Calendar.getInstance();SimpleDateFormat dateFormat= new SimpleDateFormat("yyyy-MM-dd :hh:mm:ss");System.out.println(dateFormat.format(calendar.getTime()));

3.通过Util包的Calendar 获取时间，分别获取年月日时分秒

Calendar cal=Calendar.getInstance();      int y=cal.get(Calendar.YEAR);      int m=cal.get(Calendar.MONTH);      int d=cal.get(Calendar.DATE);      int h=cal.get(Calendar.HOUR_OF_DAY);      int mi=cal.get(Calendar.MINUTE);      int s=cal.get(Calendar.SECOND);      System.out.println("现在时刻是"+y+"年"+m+"月"+d+"日"+h+"时"+mi+"分"+s+"秒");

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参考：https://blog.csdn.net/qq_34682683/article/details/78716547