Spring boot "Operation is not supported for read-only collection" when updating a record in database - spring-boot

Question

I am fairly new to Spring Boot and unable to find out why my CRUD repository seems to keep throwing an exception saying "Operation is not supported for read-only collection" when sending a request to a Put endpoint. All other repositories seem to work just fine. Here's my code:
User.kt
package com.karbal.tutortek.entities
import com.karbal.tutortek.dto.userDTO.UserPostDTO
import java.sql.Date
import javax.persistence.*
#Entity
#Table(name = "users")
data class User(
#Id
#Column(name = "id", nullable = false)
#GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "user_generator")
#SequenceGenerator(name = "user_generator", sequenceName = "user_seq", allocationSize = 1)
var id: Long? = null,
#Column(name = "firstName", nullable = false)
var firstName: String = "",
#Column(name = "lastName", nullable = false)
var lastName: String = "",
#Column(name = "birthDate", nullable = false)
var birthDate: Date = Date(System.currentTimeMillis()),
#Column(name = "rating", nullable = false)
var rating: Float = 0.0F,
#OneToMany(mappedBy = "user")
var payments: List<Payment> = listOf(),
#OneToMany(mappedBy = "user")
var topics: List<Topic> = listOf()
){
constructor(userPostDTO: UserPostDTO) : this(
null,
userPostDTO.firstName,
userPostDTO.lastName,
userPostDTO.birthDate,
userPostDTO.rating
)
fun copy(user: User){
firstName = user.firstName
lastName = user.lastName
birthDate = user.birthDate
rating = user.rating
payments = user.payments
topics = user.topics
}
}
UserController.kt
package com.karbal.tutortek.controllers
import com.karbal.tutortek.dto.userDTO.UserGetDTO
import com.karbal.tutortek.dto.userDTO.UserPostDTO
import com.karbal.tutortek.entities.User
import com.karbal.tutortek.services.UserService
import org.springframework.http.HttpStatus
import org.springframework.web.bind.annotation.*
import org.springframework.web.server.ResponseStatusException
import java.util.*
#RestController
class UserController(val userService: UserService) {
#PostMapping("/users/add")
fun addUser(#RequestBody userDTO: UserPostDTO): UserGetDTO {
val user = User(userDTO)
return UserGetDTO(userService.saveUser(user))
}
#DeleteMapping("/users/{id}")
fun deleteUser(#PathVariable id: Long){
val user = userService.getUser(id)
if(user.isEmpty) throw ResponseStatusException(HttpStatus.NOT_FOUND, "User not found")
userService.deleteUser(id)
}
#GetMapping("/users/all")
fun getAllUsers() = userService.getAllUsers().map { u -> UserGetDTO(u) }
#GetMapping("/users/{id}")
fun getUser(#PathVariable id: Long): UserGetDTO {
val user = userService.getUser(id)
if(user.isEmpty) throw ResponseStatusException(HttpStatus.NOT_FOUND, "User not found")
return UserGetDTO(user.get())
}
#PutMapping("/users/{id}")
fun updateUser(#PathVariable id: Long, #RequestBody userDTO: UserPostDTO){
val user = User(userDTO)
val userInDatabase = userService.getUser(id)
if(userInDatabase.isEmpty) throw ResponseStatusException(HttpStatus.NOT_FOUND, "User not found")
val extractedUser = userInDatabase.get()
extractedUser.copy(user)
userService.saveUser(extractedUser)
}
}
UserService.kt
package com.karbal.tutortek.services
import com.karbal.tutortek.entities.User
import org.springframework.stereotype.Service
import com.karbal.tutortek.repositories.UserRepository
#Service
class UserService(val database: UserRepository) {
fun getAllUsers(): List<User> = database.getAllUsers()
fun saveUser(user: User) = database.save(user)
fun deleteUser(id: Long) = database.deleteById(id)
fun getUser(id: Long) = database.findById(id)
}
UserRepository.kt
package com.karbal.tutortek.repositories
import com.karbal.tutortek.entities.User
import org.springframework.data.jpa.repository.Query
import org.springframework.data.repository.CrudRepository
import org.springframework.stereotype.Repository
#Repository
interface UserRepository : CrudRepository<User, Long> {
#Query("SELECT * FROM users", nativeQuery = true)
fun getAllUsers(): List<User>
}
UserPostDTO.kt
package com.karbal.tutortek.dto.userDTO
import java.sql.Date
data class UserPostDTO(
var firstName: String,
var lastName: String,
var rating: Float,
var birthDate: Date
)
The JSON that I send:
{
"firstName": "Thomas",
"lastName": "Thompson",
"rating": 4.7,
"birthDate": "2000-02-03"
}
Post works fine. Put works fine on other entities in my code. But here it always responds with 500 and a message "Operation is not supported for read-only collection". Any ideas why this could be happening?

Answer 1

Just solved this after a couple of hours. Changed lists in User class to mutable lists and now it works fine.