1、字符串转日期SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");String str = "2019-09-16 09:40:19";//字符串转日期Date date = sdf.parse(str);System.out.println("print: "+ date);

2、日期转字符串String strNew = sdf.format(date);System.out.println("strNew"+strNew);

3、日期转时间戳long time = date.getTime();System.out.println("time"+time);

4、时间戳转日期Date dateNew = new Date(time);System.out.println("dateNew"+dateNew);
