如何使用DateTimeFormatter格式化时间
String dateStr = “2021-07-21 07:17:34”;
String originalDatePattern = “yyyy-MM-dd hh:mm:ss”;
String targetDatePattern = “yyyyMMdd”;
DateTimeFormatter formatter = DateTimeFormatter.ofPattern(originalDatePattern);
String targetDate = LocalDate.parse(dateStr, formatter).format(DateTimeFormatter.ofPattern(targetDatePattern));