InvalidDefinitionException on jackson readvalue on custom class while deserialisatio

Question

I'm getting an InvalidDefinitionException on parsing json into my own custom class. Exception in thread "main" com.fasterxml.jackson.databind.exc.InvalidDefinitionException: Invalid type definition for type id.or.jisedu.repo.Book: Argument #0 of constructor [constructor for id.or.jisedu.repo.Book, annotations: [null]] has no property name annotation; must have name when multiple-parameter constructor annotated as Creator at [Source: (String)"…"

Here is the line which is causing issues:

val wrapper: BookWrapper = mapper.reader().forType(BookWrapper::class.java).readValue("""
{
  "book": {
    "publisher": "Pearson",
    "image": "https:\/\/images.isbndb.com\/covers\/34\/13\/9780134093413.jpg",
    "title_long": "Campbell Biology (11th Edition)",
    "edition": "11",
    "date_published": "2016-10-29",
    "authors": [
      "Lisa A. Urry",
      "Michael L. Cain",
      "Steven A. Wasserman",
      "Peter V. Minorsky",
      "Jane B. Reece"
    ],
    "title": "Campbell Biology (11th Edition)",
    "isbn13": "9780134093413",
    "binding": "Hardcover",
    "publish_date": "2016-10-29",
    "isbn": "0134093410"
  }
}""")

And here is my bookwrapper class:

data class BookWrapper(@JsonProperty("book") val book: Book)

@JsonInclude(JsonInclude.Include.NON_NULL)
data class Book(
  val title: String,
  @JsonProperty("title_long")
  val titleLong: String? = null,
  val isbn: String? = null,
  val isbn13: String? = null,
  val dewey_decimal: String? = null,
  val format: String? = null,
  val publisher: String? = null,
  val publish: String? = null,
  val language: String? = null,
  @JsonProperty("date_published")
  val datePublished: String? = null,
  @JsonProperty("publish_date")
  val publishDate: String? = null,
  val edition: String? = null,
  val pages: String? = null,
  val binding: String? = null,
  val dimensions: String? = null,
  val overview: String? = null,
  val excerpt: String? = null,
  val synopsys: String? = null,
  val image: String? = null,
  val authors: List<String>,
  val subjects: List<String>? = null,
  var id: Long? = null,
  var amount: Int = 1
)

---

EDIT:

I forgot to register the KotlinModule. Don't forget to do that.

Answer 1

Yes, registering KotlinModule helps. To register Kotlin module:

1. Add dependency to build.gradle:

   implementation("com.fasterxml.jackson.module:jackson-module-kotlin:2.9.8")

2. Create ObjectMapper:

   import com.fasterxml.jackson.module.kotlin.jacksonObjectMapper val mapper = jacksonObjectMapper()

More information at https://www.baeldung.com/kotlin/jackson-kotlin