[TOC] # Duration Duration:用于計算兩個“時間”間隔，以秒和納秒為基準 ## 方法  ## 例子 ~~~ LocalDateTime localDateTime = LocalDateTime.now(); LocalDateTime of = LocalDateTime.of(2018, 6, 5, 17, 25, 10); Duration duration = Duration.between(localDateTime, of); System.out.println(duration); //秒數 System.out.println(duration.getSeconds()); //納秒 System.out.println(duration.getNano()); //相隔的天數 System.out.println(duration.toDays()); ~~~ 輸出 ~~~ PT-23H-59M-42.433722S -86383 566278000 0 ~~~ PT那個負的表述少 這邊的意思是少23小時,59分鐘,后面是秒 # Period Period:用于計算兩個“日期”間隔，以年、月、日衡量 ## 方法  ## 例子 求2個日期相隔的年月日 ~~~ LocalDate localDate = LocalDate.now(); LocalDate localDate1 = LocalDate.of(2017, 3, 5); Period period = Period.between(localDate, localDate1); System.out.println(period); //取年 System.out.println(period.getYears()); //取月 System.out.println(period.getMonths()); //取天 System.out.println(period.getDays()); ~~~ 輸出 ~~~ P-1Y-3M-1D -1 -3 -1 ~~~ 指定間隔多少后的Period對象 ~~~ LocalDate localDate = LocalDate.now(); LocalDate localDate1 = LocalDate.of(2017, 3, 5); Period period = Period.between(localDate, localDate1); System.out.println(period); Period period1 = period.withYears(2); System.out.println(period1); ~~~ 輸出 ~~~ P-1Y-3M-1D P2Y-3M-1D ~~~