(I know it's more a Jackson than a Kotlin question...

# getting-started

[nkiesel]

(I know it's more a Jackson than a Kotlin question, but I hope someone might have an answer anyway). I have a line `val jackson: YAMLMapper = YAMLMapper.builder().addModule(KotlinModule()).build()`in my code to create a Jackson YAML mapper with Kotlin extensions. This tells me "Kotlin: 'constructor KotlinModule(Int = ..., Boolean = ..., Boolean = ..., Boolean = ..., SingletonSupport = ..., Boolean = ...)' is deprecated. Use KotlinModule.Builder instead of named constructor parameters". Does that really mean I should use `val jackson: YAMLMapper = YAMLMapper.builder().addModule(KotlinModule.Builder().build()).build()`instead? That's an awful amount of build...

[ephemient]

use kotlinModule { }

[nkiesel]

and how do I get the YAML mapper into that?

[Matthew Gast]

An alternative way is to use:

val jackson = ObjectMapper(YAMLFactory()).registerKotlinModule()

[nkiesel]

that will result in an ObjectMapper and not a YAMLMapper but should be ok for me because I don't think I need any YAMLMapper-specific APIs.

[Matthew Gast]

Yeah, in most cases you shouldn't

[ephemient]

kotlinModule { ... } replaces KotlinModule.Builder(). ... .build(), so you should see how to use that with YAMLMapper.builder()

[nkiesel]

right. So I have 2 options which seems equally good: ObjectMapper(YAMLFactory()).registerKotlinModule() and YAMLMapper.builder().addModule(kotlinModule()).build(). Thanks for your help!