#author("2021-06-23T17:44:29+09:00","","") [[Java]] #author("2021-06-24T15:53:20+09:00","","") [[ソフトウェア開発>SoftwareEngineering]] / [[Java>../]] / [[Java API>./]] * Java API [#u935f976] #contents * java.time [#eb43be4e] ** LocalDateTime [#oe53feb8] *** truncatedTo メソッド [#xf0c12e8] - example #highlightjs([java]) LocalDateTime localDateTime = LocalDateTime.now(); System.out.println("localDateTime :" + localDateTime); System.out.println("localDateTime.truncatedTo(ChronoUnit.DAYS) :" + localDateTime.truncatedTo(ChronoUnit.DAYS)); System.out.println("localDateTime.truncatedTo(ChronoUnit.HOURS) :" + localDateTime.truncatedTo(ChronoUnit.HOURS)); System.out.println("localDateTime.truncatedTo(ChronoUnit.MINUTES):" + localDateTime.truncatedTo(ChronoUnit.MINUTES)); System.out.println("localDateTime.truncatedTo(ChronoUnit.SECONDS):" + localDateTime.truncatedTo(ChronoUnit.SECONDS)); System.out.println("localDateTime.truncatedTo(ChronoUnit.MILLIS) :" + localDateTime.truncatedTo(ChronoUnit.MILLIS)); - result localDateTime :2019-06-15T17:35:16.723566900 localDateTime.truncatedTo(ChronoUnit.DAYS) :2019-06-15T00:00 localDateTime.truncatedTo(ChronoUnit.HOURS) :2019-06-15T17:00 localDateTime.truncatedTo(ChronoUnit.MINUTES):2019-06-15T17:35 localDateTime.truncatedTo(ChronoUnit.SECONDS):2019-06-15T17:35:16 localDateTime.truncatedTo(ChronoUnit.MILLIS) :2019-06-15T17:35:16.723 ** 型変換 [#l58e529b] *** Date => LocalDateTime [#d5531a10] - example #highlightjs([java]) Date date = new Date(); LocalDateTime localDateTime = LocalDateTime.ofInstant(date.toInstant(), ZoneId.systemDefault()); System.out.println("date :" + date); System.out.println("localDateTime:" + localDateTime); - result date :Sat Jun 15 17:51:36 JST 2019 localDateTime:2019-06-15T17:51:36.151 *** Date => LocalDate [#m8e96391] - example #highlightjs([java]) Date date = new Date(); LocalDateTime localDateTime = LocalDateTime.ofInstant(date.toInstant(), ZoneId.systemDefault()); LocalDate localDate = localDateTime.toLocalDate(); System.out.println("date :" + date); System.out.println("localDateTime:" + localDateTime); System.out.println("localDate :" + localDate); - result date :Sat Jun 15 23:08:37 JST 2019 localDateTime:2019-06-15T23:08:37.014 localDate :2019-06-15 *** LocalDateTime => LocalDate [#q6f34f5a] - example #highlightjs([java]) LocalDateTime localDateTime = LocalDateTime.now(); LocalDate localDate = localDateTime.toLocalDate(); System.out.println("localDateTime:" + localDateTime); System.out.println("localDate :" + localDate); - result localDateTime:2019-06-15T17:51:36.193991600 localDate :2019-06-15 *** LocalDateTime => Date [#j2d54ba6] - example #highlightjs([java]) LocalDateTime localDateTime = LocalDateTime.now(); Date date = Date.from(localDateTime.atZone(ZoneId.systemDefault()).toInstant()); System.out.println("localDateTime:" + localDateTime); System.out.println("date :" + date); - result localDateTime:2019-06-15T23:08:37.015564600 date :Sat Jun 15 23:08:37 JST 2019