Java 碎片化知识点
发布于 2023-08-25
获取当前时间戳
import java.time.Instant; //10位时间戳, 1692893144 long epochSecond = Instant.now().getEpochSecond(); //10位时间戳, 整型, 1692893144 int epochSecond1 = (int) Instant.now().getEpochSecond(); //13位时间戳, 1692893144845 long epochMilli = Instant.now().toEpochMilli(); //13位时间戳, 1692893144845 long currentTimeMillis = System.currentTimeMillis();
时间戳转 LocalDateTime
import java.time.Instant; import java.time.LocalDateTime; import java.time.ZoneId; LocalDateTime localDateTime = Instant.ofEpochSecond(1692893364).atZone(ZoneId.systemDefault()).toLocalDateTime(); LocalDateTime localDateTime1 = LocalDateTime.ofInstant(Instant.ofEpochSecond(1692893364), ZoneId.systemDefault()); LocalDateTime localDateTime2 = Instant.ofEpochMilli(1692893364596L).atZone(ZoneId.systemDefault()).toLocalDateTime(); LocalDateTime localDateTime3 = LocalDateTime.ofInstant(Instant.ofEpochMilli(1692893364596L), ZoneId.systemDefault());
格式化 LocalDateTime
import java.time.LocalDateTime; import java.time.format.DateTimeFormatter; //2023-08-25 00:20:53 //java8 推荐使用 DateTimeFormatter 来格式化 String format = LocalDateTime.now().format(DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss"));