JAVA中日期時間與字符串的轉換

LocalDateTime localDateTime = LocalDateTime.now();
DateTimeFormatter dateTimeFormatter = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss.SSS");
// LocalDateTime轉字符串
String localDateTimeString = localDateTime.format(dateTimeFormatter);
// 字符串轉LocalDateTime
LocalDateTime parseLocalDateTime = LocalDateTime.parse("2020-08-12 18:37:01.449",dateTimeFormatter);
System.out.println(localDateTimeString);
System.out.println(parseLocalDateTime);

Date date = new Date();
SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss.SSS");
// Date轉字符串
String formatDateString = simpleDateFormat.format(date);
// 字符串轉Date
Date parseDate = simpleDateFormat.parse("2020-08-12 18:37:01.449");
System.out.println(formatDateString);
System.out.println(parseDate);