时间和字符串格式之间的转换，以及时间差的计算方法

时间和字符串格式之间的转换，以及时间差的计算方法

1、计算时间差

方法一:
LocalDateTime now = LocalDateTime.now();
LocalDateTime end = LocalDateTime.now();
Duration duration = Duration.between(now,end);
//相差的天数
long days = duration.toDays(); 
//相差的小时数
long hours = duration.toHours();
//相差的分钟数
long minutes = duration.toMinutes();
//相差毫秒数
long millis = duration.toMillis();
//相差的纳秒数
long nanos = duration.toNanos();

方法二:
final LocalDateTime fromDate = LocalDateTime.now();
final LocalDateTime toDate = LocalDateTime.now().plusHours(56); 
long minutes = ChronoUnit.MINUTES.between(fromDate, toDate);
long hours = ChronoUnit.HOURS.between(fromDate, toDate);

2、时间和字符串格式之间的转换

2.1、String转LocalDateTime

String str = "1986-04-08 12:30";
DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm");
LocalDateTime dateTime = LocalDateTime.parse(str, formatter);

2.2、LocalDateTime转String

DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm");
// "1986-04-08 12:30"
LocalDateTime dateTime = LocalDateTime.of(1986, Month.APRIL, 8, 12, 30);
String formattedDateTime = dateTime.format(formatter); 

2.3、将LocalDateTime转换为时区ISO 8601字符串

LocalDateTime ldt = LocalDateTime.now(); 
//you might use a different zone
ZonedDateTime zdt = ldt.atZone(ZoneOffset.UTC); 
String iso8601 = zdt.toString();

2.4、将ISO 8601字符串转换回LocalDateTime

String iso8601 = "2016-02-14T18:32:04.150Z";
ZonedDateTime zdt = ZonedDateTime.parse(iso8601);
LocalDateTime ldt = zdt.toLocalDateTime();