在Clojure中获取日期和时间的最佳方式是什么？

Question

I need to log some events on a Clojure Client-Server scenario, but it seems to me that Clojure does not provide a date/time function. Can any one confirm this or I am missing something here?! If I am correct then I need to use java interop, right?

Answer 1

If all you need is to get the current time and date for your logger, then this function is OK:

 (defn now [] (new java.util.Date))

Now that you mentioned this, it would be useful to have support for immutable Date objects.

Answer 2

Java 1.8 added the java.time package to the core JDK to clean up many of the frustrations with the state of date & time in Java. Since java.time is now a widely available part of core Java with a much improved API, I would encourage you to give it the first look when writing new date & time code.

Here's how you can retrieve the current date and time:

(java.time.LocalDateTime/now)

Answer 3

There is a Clojure-wrapper library for Joda-Time . Or you'll have to use java interop with the standard Java API.

Answer 4

With clj-time , the Clojure library that wraps the Java Joda Time library, you could use code like the following:

(require '[clj-time.core :as time])
(require '[clj-time.format :as time-format])

(time/now) => #<DateTime 2013-03-31T03:23:47.328Z>

(def time-formatter (time-format/formatters :basic-date-time))  ;; ISO 8601 UTC format
(time-format/unparse custom-formatter (date-time 2010 10 3)) => "20101003T000000.000Z"

One benefit of Joda Time (and hence clj-time) is that new releases support new changes to time zones.

Answer 5

如果你不需要更高级的东西，只需使用Java类。

(.format (java.text.SimpleDateFormat. "MM/dd/yyyy") (new java.util.Date))