本文用示例介绍java的Duration的用法。
说明
Duration类通过秒和纳秒相结合来描述一个时间量,最高精度是纳秒。时间量可以为正也可以为负,比如1天(86400秒0纳秒)、-1天(-86400秒0纳秒)、1年(31556952秒0纳秒)、1毫秒(0秒1000000纳秒)等。
Period类通过年、月、日相结合来描述一个时间量,最高精度是天。时间量可以为正也可以为负,例如2年(2年0个月0天)、3个月(0年3个月0天)、4天(0年0月4天)等。
这两个类是不可变的、线程安全的、最终类。都是JDK8新增的。
Period用法
基于天、时、分、秒、纳秒创建。
ofDays(), ofHours(), ofMillis(), ofMinutes(), ofNanos(), ofSeconds()。例如:
1 | Duration fromDays = Duration.ofDays( 1 ); |
通过LocalDateTime或者LocalTime 类,然后使用between获取创建Duration。
1 2 3 4 | LocalDateTime start = LocalDateTime.of( 2022 , 1 , 1 , 8 , 0 , 0 ); LocalDateTime end = LocalDateTime.of( 2022 , 1 , 2 , 8 , 30 , 30 ); Duration duration = Duration.between(start, end); |
1 2 | Duration du1 = Duration.ofHours( 10 ); Duration duration = Duration.from(du1); |
用法示例
1 2 | Duration fromChar1 = Duration.parse( "P1DT1H10M10.5S" ); Duration fromChar2 = Duration.parse( "PT10M" ); |
格式说明
采用ISO-8601时间格式。格式为:PnYnMnDTnHnMnS (n为个数)
例如:P1Y2M10DT2H30M15.03S
P:开始标记
1Y:一年
2M:两个月
10D:十天
T:日期和时间的分割标记
2H:两个小时
30M:三十分钟
15S:15.02秒
1."P", "D", "H", "M" 和 "S"可以是大写或者小写(建议大写)
2.可以用“-”表示负数
示例大全
"PT20.345S" -- parses as "20.345 seconds"
"PT15M" -- parses as "15 minutes" (where a minute is 60 seconds)
"PT10H" -- parses as "10 hours" (where an hour is 3600 seconds)
"P2D" -- parses as "2 days" (where a day is 24 hours or 86400 seconds)
"P2DT3H4M" -- parses as "2 days, 3 hours and 4 minutes"
"P-6H3M" -- parses as "-6 hours and +3 minutes"
"-P6H3M" -- parses as "-6 hours and -3 minutes"
"-P-6H+3M" -- parses as "+6 hours and -3 minutes"
源码:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 | public final class Duration implements TemporalAmount, Comparable<Duration>, Serializable { //其他代码 //----------------------------------------------------------------------- /** * Obtains a {@code Duration} from a text string such as {@code PnDTnHnMn.nS}. * <p> * This will parse a textual representation of a duration, including the * string produced by {@code toString()}. The formats accepted are based * on the ISO-8601 duration format {@code PnDTnHnMn.nS} with days * considered to be exactly 24 hours. * <p> * The string starts with an optional sign, denoted by the ASCII negative * or positive symbol. If negative, the whole period is negated. * The ASCII letter "P" is next in upper or lower case. * There are then four sections, each consisting of a number and a suffix. * The sections have suffixes in ASCII of "D", "H", "M" and "S" for * days, hours, minutes and seconds, accepted in upper or lower case. * The suffixes must occur in order. The ASCII letter "T" must occur before * the first occurrence, if any, of an hour, minute or second section. * At least one of the four sections must be present, and if "T" is present * there must be at least one section after the "T". * The number part of each section must consist of one or more ASCII digits. * The number may be prefixed by the ASCII negative or positive symbol. * The number of days, hours and minutes must parse to an {@code long}. * The number of seconds must parse to an {@code long} with optional fraction. * The decimal point may be either a dot or a comma. * The fractional part may have from zero to 9 digits. * <p> * The leading plus/minus sign, and negative values for other units are * not part of the ISO-8601 standard. * <p> * Examples: * <pre> * "PT20.345S" -- parses as "20.345 seconds" * "PT15M" -- parses as "15 minutes" (where a minute is 60 seconds) * "PT10H" -- parses as "10 hours" (where an hour is 3600 seconds) * "P2D" -- parses as "2 days" (where a day is 24 hours or 86400 seconds) * "P2DT3H4M" -- parses as "2 days, 3 hours and 4 minutes" * "P-6H3M" -- parses as "-6 hours and +3 minutes" * "-P6H3M" -- parses as "-6 hours and -3 minutes" * "-P-6H+3M" -- parses as "+6 hours and -3 minutes" * </pre> * * @param text the text to parse, not null * @return the parsed duration, not null * @throws DateTimeParseException if the text cannot be parsed to a duration */ public static Duration parse(CharSequence text) { ...... } } |
比较两个时间的差
1 2 3 4 5 6 7 8 9 10 11 | Instant start = Instant.parse( "2017-10-03T10:15:30.00Z" ); Instant end = Instant.parse( "2017-10-03T10:16:30.00Z" ); // start - end Duration duration = Duration.between(start, end); // 任何一个时间单元为负数,则返回true。true:end早于start duration.isNegative(); Duration.between(start, end).getSeconds(); Duration.between(start, end).getNano(); |
plusX()、minusX()
X表示days, hours, millis, minutes, nanos 或 seconds
1 2 | Duration duration = Duration.ofHours( 2 ); Duration newDuration = duration.plusSeconds( 33 ); |
plus()/minus()方法
带TemporalUnit 类型参数进行加减:
1 2 | Duration duration = Duration.ofHours( 2 ); Duration newDuration = duration.plus( 33 , ChronoUnit.SECONDS); |
可以用toX来转换为其他单位,支持:toDays, toHours, toMinutes, toMillis, toNanos
1 2 3 4 5 6 7 | Duration duration = Duration.ofHours( 2 ); duration.toDays(); // 0 duration.toHours(); // 2 duration.toMinutes(); // 120 duration.toMillis(); // 7200000 duration.toNanos(); // 7200000000000 |
可以用getX来获得指定位置的值,因为Duration是由秒和纳秒组成,所以只能获得秒和纳秒:
1 2 3 4 | Duration duration = Duration.ofHours( 2 ); duration.getSeconds(); //7200 duration.getNano(); // |
以上就是详解Java中Duration类的使用方法的详细内容,更多关于Java Duration类的资料请关注脚本之家其它相关文章!