Kotlin and Spring Data JPA produces PropertyReferenceException

Question

I am currently using Kotlin 1.2 and Spring Boot 2.0 M7 with Spring Data JPA. In this project I am using a custom base repository instead of JPARepository or PagingAndSortingRepository (really doesn't matter)

Here is the base interface

@NoRepositoryBean
interface BaseRepository<T, ID : Serializable> : Repository<T, ID> {
    fun <S : T> save(entity: S): S
    fun findOne(id: ID): T?
    fun findAll(): List<T>
    fun count(): Long
}

and here is the actual repository

interface ArticleRepository : BaseRepository<Article, Int> {
}

and finally here is the Article data class

@Entity
@Table(name = "article")
@Cacheable
data class Article (
    @Id
    @GeneratedValue(strategy = IDENTITY)
    @Column(name = "id", unique = true, nullable = false)
    var id: Int? = null,

    @ManyToOne(fetch = FetchType.LAZY)
    @JoinColumn(name = "member_id", nullable = false)
    var member: Member? = null,

    @Column(name = "title", nullable = false, length = 200)
    var title: String = "",

    @Column(name = "content", nullable = false, length = 65535)
    var content: String = "",

    @Column(name = "last_modified", nullable = false, length = 19)
    var lastModified: LocalDateTime = LocalDateTime.now(),

    @Column(name = "deleted", nullable = false)
    var deleted: Boolean = false,

    @Column(name = "effective_start", length = 19)
    var effectiveStart: LocalDateTime? = null,

    @Column(name = "effective_end", length = 19)
    var effectiveEnd: LocalDateTime? = null,

    @Version
    @Column(name = "version", nullable = false)
    var version: Int = 0
): Serializable {
    constructor() : this(null)
    constructor(member: Member, title: String, content: String, lastModified: LocalDateTime, deleted: Boolean) : this(null, member, title, content, lastModified, deleted)
}

But upon start up, I get this weird error

Caused by: java.lang.IllegalArgumentException: Failed to create query for method public abstract java.lang.Object com.nokia.srandu.oms.corrviewer.db.repo.BaseRepository.findOne(java.io.Serializable)! No property findOne found for type Article!
.
.
.
Caused by: org.springframework.data.mapping.PropertyReferenceException: No property findOne found for type Article!

I think this is related to https://jira.spring.io/browse/DATACMNS-1223 but what can I do as a work around for this? Transferring the interface to Java did not help either.

Why do you create a BaseRepository? There is a JPARepository in Spring Data that you could use. — Simon Martinelli, Jan 11 '18 at 08:23
@SimonMartinelli actually, if I use the JPARepository, it is still the same error but on different methods. I didnt use the JPARepository because I didn't want to expose the physical delete method — Robby F, Jan 11 '18 at 10:36

score 2 · Accepted Answer · answered Jan 11 '18 at 08:33

The method name conventions for repositories have changed in Spring Data 2.0:

fun findOne(…): T? -> fun findById(…): Optional<T>

If you would like to continue to get a simple nullable type instead of an Optional, declare an additional or alternate query method fun getById(…): T? and it should work as expected.

Kotlin and Spring Data JPA produces PropertyReferenceException

1 Answers1