diff --git a/s-day01/src/com/inmind/jdk8_time04/InstantDemo11.java b/s-day01/src/com/inmind/jdk8_time04/InstantDemo11.java new file mode 100644 index 0000000..bdfaca3 --- /dev/null +++ b/s-day01/src/com/inmind/jdk8_time04/InstantDemo11.java @@ -0,0 +1,36 @@ +package com.inmind.jdk8_time04; + +import java.time.Instant; + +/** + * 目标:掌握Instant的使用。 + */ +public class InstantDemo11 { + public static void main(String[] args) { + //1.创建时间戳对象 + Instant now = Instant.now(); + + //2.获取总秒数(计算机基准时间开始算的) + long epochSecond = now.getEpochSecond(); + System.out.println(epochSecond); + //3.不够1秒的纳秒值 + System.out.println(now.getNano()); + //4.打印对象:总秒数+纳秒数 + System.out.println(now);//重写toString + //5.对时间点的加减 + Instant instant1 = now.plusSeconds(60); + Instant instant2 = now.minusSeconds(60); + System.out.println(instant1); + System.out.println(instant2); + //6.Instant对象的作用:做代码的性能分析,或者记录用户的操作时间点 + Instant start = Instant.now(); + //业务代码的执行.... + for (int i = 0; i < 100; i++) { + System.out.println(1); + } + Instant end = Instant.now(); + //todo 之后使用间隔来计算时间的差 + + //传统的Date类,只能精确到毫秒,并且是可变对象,而Instant可以精确到纳秒,并且不可改变对象,推荐使用Instant,但一般LocalDateTime也够用了 + } +}