Is there a jackson datatype module for JDK8 java.time?

Question

I'm looking for a module for the new JDK8 java.time classes. I have looked through the FasterXML GitHub Project Listing and presently found none.

As I understand Jackson is still being compiled against JDK6 so can not use these classes directly and must have this built as a separate module, as was required with Joda.

I don't mind starting the project, though looking to see if any other efforts were already underway.

Solution 1

As already mentioned, Jackson-Datatype-JSR310 provides support for Java 8 Time.

Since Jackson 2.6.0 the "old" JSR310Module is deprecated. It is replaced by JavaTimeModule. Maven dependency is the same (you can find the current version in Maven Central):

<dependency>
    <groupId>com.fasterxml.jackson.datatype</groupId>
    <artifactId>jackson-datatype-jsr310</artifactId>
    <version>2.6.0</version>
</dependency>

You have to register the module like this:

ObjectMapper mapper = new ObjectMapper();
mapper.registerModule(new JavaTimeModule());

Or like this:

ObjectMapper mapper = new ObjectMapper(); 
mapper.findAndRegisterModules();

Or like this (since 2.10 possible):

ObjectMapper mapper = JsonMapper.builder()
        .findAndAddModules()
        .build();

Note that as of 2.6, this module does NOT support auto-registration, because of existence of legacy version, JSR310Module. Legacy version has the same functionality, but slightly different default configuration: see com.fasterxml.jackson.datatype.jsr310.JSR310Module for details.

JavaTimeModule Source at GitHub

JavaTimeModule Usage

Solution 2

The most complete listing of datatype modules would be found from Jackson "portal" page at Github:

https://github.com/FasterXML/jackson

which does list "JSR-310: support for "Java 8 Dates". Naming is bit opaque, but it refers to the standardization process, via JSR that should be finalized to produce the new Java8 Date API (if it's not already final; process has taken a while).

Direct link is: https://github.com/FasterXML/jackson-datatype-jsr310

Solution 3

If you use Spring Boot 2 and depends on the spring-boot-starter-web starter, you would have as dependencies both : the deprecated (jackson-datatype-jsr310) and the actual (jackson-datatype-jdk8).

[INFO] +- org.springframework.boot:spring-boot-starter-web:jar:2.0.0.M3:compile
[INFO] |  +- org.springframework.boot:spring-boot-starter-json:jar:2.0.0.M3:compile
[INFO] |  |  +- com.fasterxml.jackson.datatype:jackson-datatype-jdk8:jar:2.9.0.pr4:compile
[INFO] |  |  +- com.fasterxml.jackson.datatype:jackson-datatype-jsr310:jar:2.9.0.pr4:compile

Solution 4

You just need to import the jsr310 module.

<dependency>
    <groupId>com.fasterxml.jackson.datatype</groupId>
    <artifactId>jackson-datatype-jsr310</artifactId>
    <version>2.5.0</version>
</dependency>

If module auto scan is not enable in your project, you will need to register it:

ObjectMapper mapper = new ObjectMapper();
mapper.registerModule(new JSR310Module());

Solution 5

My bad, I was looking for a jackson-datatype-jdk8 as was for jackson-datatype-jdk7, however the project was actually created under the JSR name jackson-datatype-jsr310.

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Comments

[Brett Ryan]

Thanks, I did manage to find it immediately after posting the question.

[KIC]

Note that you also have to register the modules i.e. like so: ` private static final ObjectMapper jsonMapper = new ObjectMapper().findAndRegisterModules();`

[Wivani]

Especially helpful answer because it mentions the name change, and the extra warning about auto-regsitration.

[Youcef Laidani]

Hi David, what the good day to read your answer, I have the same problem and I try to solve it :D I got java.lang.NoClassDefFoundError: com/fasterxml/jackson/annotation/JsonCreator$Mode

[Youcef Laidani]

I solved my issue by only checking Include dependencies with "Provided Scope" in Intellij congiguration :D

[davidxxx]

Hello Youcef. And that is good day for me too to read you :) IntelliJ, our savoir : ) And finally how did you solve the issue ? :)

[Youcef Laidani]

Hi David, Yes, as I said I just checked Edit Configuration > Include dependencies with "Provided Scope" that solve the issue ;)

[davidxxx]

Oh yes, Youcef : "check" for marking and not "check" for verifying :)

[Youcef Laidani]

Ah sorry, yes I mean click on the checkbox ;)