I use spring boot data mongodb in my scala project. When saving a case class that contains a lazy val, an additional bitmap$0 field appears in the mongo document (even if lazy val field is annotated with org.springframework.data.annotation.Transient). For example:
case class User(val firstName: String, val lastName: String) {
#Transient lazy val fullName: String = firstName +' ' + lastName
}
trait UserMongoRepository extends MongoRepository[User, String]
#Service
class userService(userMongoRepository: UserMongoRepository){
def saveUser = {
val u = User("Bob", "Marley")
userMongoRepository.save(u)
}
}
This results in a document:
{"firstName": "Bob", "lastName": "Marley", "bitmap$0": false}
How do I save a class with lazy val without the bitmap$0 field?
Related
I have an application.properties file like:
person-one-name=John
This is my data class, I have used #Value annotation outside dataclass.
#Value("\${person-one-name}")
lateinit var personOne: String
data class Person(val name: String, val age: Int) {
constructor(age: Int) : this(personOne, age)
}
I want to use the var personOne in my data class.
It gives an error lateinit property personOne has not been initialized
Following on from my comment under the Question:
data class Person(val name: String, val age: Int)
#Service
class PersonFactory(
#Value("\${person-one-name}")
private val personOne: String,
) {
fun createPerson(name: String? = null, age: Int) =
if (name != null) Person(name, age)
else Person(personOne, age)
}
Another gotcha, is that the PersonFactory service needs to be in a package at the same level or within the class that starts the App.
More info: https://springhow.com/a-guide-to-value-in-spring-boot/
I am using Spring Data MongoDB with Kotlin Coroutines to create a non-blocking server.
I have a document Deck:
#Document
data class Deck(
#Id val id: ObjectId = ObjectId.get(),
#DocumentReference(lazy = true) val author: User,
val title: String,
val desc: String,
#DocumentReference(lazy = true) val cards : Set<Card> = emptySet(),
#CreatedDate val createdAt: Instant = Instant.now(),
#LastModifiedDate val lastModifiedAt: Instant = Instant.now()
)
Deck has a reference to a User type in the author field:
#Document
data class User(
#Id val id: ObjectId = ObjectId.get(),
val name: String,
#Indexed(unique = true, name = "username_index") val username: String,
val password: String,
#CreatedDate val createdAt: Instant = Instant.now(),
#LastModifiedDate val lastModifiedAt: Instant = Instant.now(),
#DocumentReference(lazy = true) val decks: Set<Deck> = emptySet()
)
Here's my DeckRepository interface:
interface DeckRepository: CoroutineSortingRepository<Deck, String> {
}
The Deck documents are getting saved properly in the database with the author's ObjectId.
But when I try to fetch the deck with id, the repository method gives an error. It's not able to populate the author's reference.
override suspend fun getDeck(deckId: String): DeckResponseDTO {
log.info("Getting deck with id $deckId")
return deckRepository.findById(deckId)?.toDto() ?: throw Exception("Could not find deck with id $deckId")
}
Stacktrace snippets:
Failed to instantiate io.gitub.startswithzed.dex.model.Deck using constructor fun <init>(org.bson.types.ObjectId, io.gitub.startswithzed.dex.model.User, kotlin.String, kotlin.String, kotlin.collections.Set<io.gitub.startswithzed.dex.model.Card>, java.time.Instant, java.time.Instant): io.gitub.startswithzed.dex.model.Deck with arguments 63173407712ec0263535829a,null,Test title,Test Desc,null,2022-09-06T11:50:31.370Z,2022-09-06T11:50:31.370Z,16,null
at org.springframework.data.mapping.model.KotlinClassGeneratingEntityInstantiator$DefaultingKotlinClassInstantiatorAdapter.createInstance(KotlinClassGeneratingEntityInstantiator.java:215) ~[spring-data-commons-2.7.2.jar:2.7.2]
Caused by: java.lang.NullPointerException: Parameter specified as non-null is null: method io.gitub.startswithzed.dex.model.Deck.<init>, parameter author
at io.gitub.startswithzed.dex.model.Deck.<init>(Deck.kt) ~[main/:na]
at io.gitub.startswithzed.dex.model.Deck.<init>(Deck.kt:14) ~[main/:na]
I even verified the data by querying using lookup in the console. Somehow Spring Data is not able to query properly.
Thanks for the help!
I have two DTOs
One for a get method like "/pessoas/{id}"
And another one for "/pessoas/{id}/detalhes" where I am going to see more attributes of Pessoa.
My codes are in Kotlin.
My simple DTO:
interface PessoaDTO {
val idInstitucional: UUID?
val nome: String?
}
data class PessoaDTOImpl(override val idInstitucional: UUID?, override val nome: String?): PessoaDTO
My DTO with details:
interface PessoaDetalhesDTO {
val idInstitucional: UUID?
val nome: String?
val email: String?
val telefone: String?
val cpf: Long?
}
data class PessoaDetalhesDTOImpl(override val idInstitucional: UUID?, override val nome: String?, override val email: String?, override val telefone: String?, override val cpf: Long?): PessoaDetalhesDTO
I have a repository that will be accessed by my PessoaController. I was thinking about having two methods in my Repository, each one for a different DTO.
That's my Repository:
internal interface PessoaRepository : CrudRepository<Pessoa, Long>, JpaSpecificationExecutorWithProjection<Pessoa> {
fun findByIdInstitucional(idInstitucional: UUID): PessoaDTO?
fun findByIdInstitucional(idInstitucional: UUID): PessoaDetalhesDTO?
}
However, I can't have two functions with the same name in the Repository for different returned data types.
How can I deal with that without having to create another Repository for the detailed information of Pessoa?
I'm new to ROOM library. I've some complex json data structure which i would like to store in ROOM database, i don't know how to use Type convertes for multiple list of objectes. Following are my Entities,
// Trying to put all my custom models in a single table
#Entity(tableName = "myTable")
data class RaceModelDatabase(
#PrimaryKey
val ID: String,
#Embedded val info: CustomModel,
#Embedded(prefix = "parti")
val parti: Map<String,UserModelDatabase> ,
#Embedded val totalTime: Map<String,TimeDataModel>
)
// Custom Models which also has Map objects
data class CustomModel (val name :String, val crdate : String )
data class UserModelDatabase(#Embedded val info : CustomModel,
#Embedded(prefix = "Result_") val result :Map<String,CustomModel>
)
data class TimeDataModel (
val Start : Long,
val End : Long
)
Here is an example of how to use TypeAdapter for one of your Map objects. You could follow the same for the rest.
class RaceTypeConverter {
#JvmStatic
#TypeConverter
fun fromString(value: String): Map<String, TimeDataModel > {
val mapType = object : TypeToken<Map<String, TimeDataModel >>() {}.type
return Gson().fromJson(value, mapType)
}
#TypeConverter
#JvmStatic
fun fromStringMap(map: Map<String, TimeDataModel>): String {
val gson = Gson()
return gson.toJson(map)
}
}
I have a collection, with documents having a field named _id of type String, not generated manually.
I have been trying to get a document using its id.
val criteria = Criteria.where("_id").`is`("a2z3e44R")
val document = mongoTemplate.findOne(Query.query(criteria), MyDocument::class.java) // returns null
val criteria = Criteria.where("_id").`is`(ObjectId("a2z3e44R"))
val document = mongoTemplate.findOne(Query.query(criteria), MyDocument::class.java) // returns null
val document = mongoTemplate.findById("a2z3e44R", MyDocument::class.java) // returns null
mongoTemplate.findAll(MyDocument::class.java).first { myDocument ->
myDocument._id == "a2z3e44R"
} // OK...
MyDocument is
data class MyDocument(val _id: String, val name: String)
Trying to find a document by another field works.
An idea of what I could be missing or a workaround?
You should indicate the type of the id like this
public class Article {
#MongoId(value = FieldType.OBJECT_ID)
private String id;
private String title;
private String desc;
}
Try mark _id with annotation #Id. The #Id annotation is used to specify the identifier for Spring.
data class MyDocument(#Id val _id: String, val name: String)
Ypu could define in your repository:
public interface MyDocumentRepository extends MongoRepository<MyDocument, String> {
Pets findBy_id(ObjectId _id);
}
and use it :
myDocumentRepository.findBy_id("a2z3e44R");
for more info see
or
ObjectId objID = new ObjectId("a2z3e44R");
query.addCriteria(Criteria.where("_id").lt(objID));
like this other answer link