With the upgrade Arrow-Jackson integration fails: ```arrow/core/Validated java.lang.NoClassDefFoundE...

# arrow

[Oğuzhan Soykan]

With the upgrade Arrow-Jackson integration fails:

arrow/core/Validated
java.lang.NoClassDefFoundError: arrow/core/Validated
	at arrow.integrations.jackson.module.ValidatedSerializerResolver.<init>(ValidatedModule.kt:34)
	at arrow.integrations.jackson.module.ValidatedModule.setupModule(ValidatedModule.kt:27)
	at com.fasterxml.jackson.databind.ObjectMapper.registerModule(ObjectMapper.java:908)
	at com.fasterxml.jackson.databind.ObjectMapper.registerModules(ObjectMapper.java:1090)
	at arrow.integrations.jackson.module.ArrowModuleKt.registerArrowModule(ArrowModule.kt:10)
	at arrow.integrations.jackson.module.ArrowModuleKt.registerArrowModule$default(ArrowModule.kt:5)

And I think the last update is last year: https://github.com/arrow-kt/arrow-integrations
Do you folks recommend a workaround or hold the bump until jackson module is also fixed?

[Alejandro Serrano.Mena]

indeed, the module needs to be fixed

[Alejandro Serrano.Mena]

so I guess waiting for the new version is the only "fix" for now

[Oğuzhan Soykan]

I was using only Option module, so copied this module to my codebase and registered to Jackson, it worked as a workaround for now.

[Alejandro Serrano.Mena]

I've made a PR about this https://github.com/arrow-kt/arrow-integrations/pull/125

may I kindly request for you to have a look at it? I'm by no means an expert on Jackson, and it would be nice to double check that I haven't done anything stupid

[Wilson Chuks]

Even with latest arrow `2.0.1`and latest io.arrow-kt:arrow-integrations-jackson-module:0.15.1

Arrow - Jackson integration still fails for NonEmptyList and NonEmptySet as both have been changed to `value classes`and it seems jackson has a long standing issue with value classes.

this is a big problem as NonEmptyList and NonEmptySet can easily be passed to List and Set.

Any ideas for solution guys?

[Alejandro Serrano.Mena]

part of this is a compiler bug which we've already reported https://github.com/arrow-kt/arrow/issues/3557

[Alejandro Serrano.Mena]

@Wilson Chuks some progress has been done on the serialization of NonEmptyList https://github.com/arrow-kt/arrow/pull/3580, the problem with nested fields should be fixed when the Kotlin compiler is fixed