Java 獲取昨天、當前、明天的時間

SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMdd"); 20190705
Calendar c = Calendar.getInstance();
c.add(Calendar.DATE, -1);//-1.昨天時間 0.當前時間 1.明天時間 *以此類推
String time = sdf.format(c.getTime());
System.out.println("昨天的時間時間是：" + time);//20190704

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 Date nowDate = new Date();
 Calendar calendar = Calendar.getInstance();
 calendar.setTime(nowDate);
 calendar.add(Calendar.DAY_OF_YEAR, -15);
 long last1FifteenTime = calendar.getTime().getTime();//獲取到15天之前得毫秒值
 System.err.println(last1FifteenTime);
 Date date = new Date();
 Long time = date.getTime();//當前時間得毫秒
 Date d = new Date(time);
 SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");//轉字符串
 System.out.println(sdf.format(d));