A date and time library for Clojure, wrapping the Joda Time library.
clj-time artifacts are released to Clojars.
If you are using Maven, add the following repository definition to your
<repository> <id>clojars.org</id> <url>http://clojars.org/repo</url> </repository>
<dependency> <groupId>clj-time</groupId> <artifactId>clj-time</artifactId> <version>0.6.0</version> </dependency>
Please open issues against the official clj-time repo on Github.
Note: version 0.6.0 introduces a number of API changes to improve consistency.
The API now uses
millis where it previously had
msecs. The older API is still present but marked as deprecated (and calling deprecated functions will print a message to the console as well returning the result). The older API will be removed in version 0.7.0 so be prepared to update your code.
The main namespace for date-time operations in the
clj-time library is
=> (use 'clj-time.core)
Create a DateTime instance with date-time, specifying the year, month, day, hour, minute, second, and millisecond:
=> (date-time 1986 10 14 4 3 27 456) #<DateTime 1986-10-14T04:03:27.456Z>
Less-significant fields can be omitted:
=> (date-time 1986 10 14) #<DateTime 1986-10-14T00:00:00.000Z>
Get the current time with
(now) and the start of the Unix epoch with
Once you have a date-time, use accessors like
second to access the corresponding fields:
=> (hour (date-time 1986 10 14 22)) 22
The date-time constructor always returns times in the UTC time zone. If you want a time with the specified fields in a different time zone, use
=> (from-time-zone (date-time 1986 10 22) (time-zone-for-offset -2)) #<DateTime 1986-10-22T00:00:00.000-02:00>
If on the other hand you want a given absolute instant in time in a different time zone, use
=> (to-time-zone (date-time 1986 10 22) (time-zone-for-offset -2)) #<DateTime 1986-10-21T22:00:00.000-02:00>
In addition to
time-zone-for-offset, you can use the
default-time-zone functions and the
utc Var to construct or get
If you only want a date with no time component, consider using the
LocalDate instances that do not have time components (and thus don't suffer from timezone-related shifting).
=> (local-date 2013 3 20) #<LocalDate 2013-03-20>
before? determine the relative position of two
=> (after? (date-time 1986 10) (date-time 1986 9)) true
Often you will want to find a date some amount of time from a given date. For example, to find the time 1 month and 3 weeks from a given date-time:
=> (plus (date-time 1986 10 14) (months 1) (weeks 3)) #<DateTime 1986-12-05T00:00:00.000Z>
Interval is used to represent the span of time between two
instances. Construct one using
interval, then query them using
=> (within? (interval (date-time 1986) (date-time 1990)) (date-time 1987)) true
in-minutes functions can be used to describe intervals in the corresponding temporal units:
=> (in-minutes (interval (date-time 1986 10 2) (date-time 1986 10 14))) 17280
If you need to parse or print date-times, use
=> (use 'clj-time.format)
Printing and printing are controlled by formatters. You can either use one of the built in ISO8601 formatters or define your own, e.g.:
(def built-in-formatter (formatters :basic-date-time)) (def custom-formatter (formatter "yyyyMMdd"))
To see a list of available built-in formatters and an example of a date-time printed in their format:
mm is minutes,
MM is months,
ss is seconds and
SS is milliseconds.
Once you have a formatter, parsing and printing are straightforward:
=> (parse custom-formatter "20100311") #<DateTime 2010-03-11T00:00:00.000Z> => (unparse custom-formatter (date-time 2010 10 3)) "20101003"
To parse dates in multiple formats and format dates in just one format, you can do this:
=> (def multi-parser (formatter (default-time-zone) "YYYY-MM-dd" "YYYY/MM/dd")) => (unparse multi-parser (parse multi-parser "2012-02-01")) "2012-02-01" => (unparse multi-parser (parse multi-parser "2012/02/01")) "2012-02-01"
clj-time.core/today-at returns a moment in time at the given hour, minute and second
on the current date:
=> (today-at 12 00) #<DateTime 2013-03-29T12:00:00.000Z> => (today-at 12 00 05) #<DateTime 2013-03-29T12:00:05.000Z>
clj-time.coerce contains utility functions for coercing Joda
DateTime instances to and from various other types:
=> (use 'clj-time.coerce)
For example, to convert a Joda
DateTime to and from a Java
=> (to-long (date-time 1998 4 25)) 893462400000 => (from-long 893462400000) #<DateTime 1998-04-25T00:00:00.000Z>
And by the magic of protocols you can pass in an isoformat string and get the unix epoch milliseconds:
=> (to-long "2013-08-01") 1375315200000
There are also conversions to and from
from-sql-time) and several other types.
clj-time.local contains functions for working with local time without having to shift to/from utc,
the preferred time zone of clj-time.core.
Get the current local time with
Get a local date-time instance retaining the time fields with
=> (to-local-date-time obj)
The following all return 1986-10-14 04:03:27.246 with the local time zone.
(to-local-date-time (clj-time.core/date-time 1986 10 14 4 3 27 246)) (to-local-date-time "1986-10-14T04:03:27.246") (to-local-date-time "1986-10-14T04:03:27.246Z")
The dynamic var *local-formatters* contains a map of local formatters for parsing and printing. It is initialized with all the formatters in clj-time.format localized.
to-local-date-time for strings uses *local-formatters* to parse.
Format an obj using a formatter in *local-formatters* corresponding to the format-key passed in with
=> (format-local-time (local-now) :basic-date-time)
clj-time.periodic/periodic-seq returns an infinite sequence of instants
separated by a time period starting with the given point in time:
(use 'clj-time.periodic) (use 'clj.time.core) ;; returns 10 instants starting with current time separated ;; by 12 hours (take 10 (periodic-seq (now) (hours 12)))
Running the tests:
$ lein test-all
(assumes Leiningen 2.x)
The complete API documentation is also available (codox generated).
Released under the MIT License: https://github.com/clj-time/clj-time/blob/master/MIT-LICENSE.txt