Preferences.kt

package org.craftsrecords.talkadvisor.infra.resources

import org.craftsrecords.talkadvisor.recommendation.preferences.Preferences as DomainPreferences
import org.craftsrecords.talkadvisor.recommendation.preferences.Topic as DomainTopic
import org.craftsrecords.talkadvisor.recommendation.talk.TalkFormat as DomainTalkFormat

data class Preferences(val topics: List<Topic>, val talksFormats: List<String>) {
    fun toDomainObject(): DomainPreferences {
        return DomainPreferences(topics.toDomainObjects(), talksFormats.toDomainTalkFormats())
    }
}

Topic.kt

package org.craftsrecords.talkadvisor.infra.resources

import org.craftsrecords.talkadvisor.recommendation.preferences.Topic as DomainTopic

class Topic(val name: String) {
    fun toDomainObject(): DomainTopic {
        return DomainTopic(this.name)
    }
}

fun Iterable<Topic>.toDomainObjects(): Set<DomainTopic> {
    return this.map(Topic::toDomainObject).toSet()
}