kotlin data class with annotations, why @DateTimeFormat annotation works without targetting

Question

data class UserSearchRequest(
        @field:NotNull
        val active: Boolean?,
        // no targeting work
        @DateTimeFormat(iso = DateTimeFormat.ISO.DATE) 
        @field:NotNull
        val registeredDate: LocalDate,
)

why @DateTimeFormat annotation works without targetting?

Answer 1

you registered kotlin module, it allows you to apply jackson annotations to constructor params without targeting but it doesn't work for java validation like your NotNull annotations