EJB Container initialization error, could not invoke defineClass

Question

My glassfish throws an exception when I try to run.

[2018-02-22T17:07:04.135+0100] [glassfish 5.0] [SEVERE] [] [javax.enterprise.system.core] [tid: _ThreadID=46 _ThreadName=admin-listener(4)] [timeMillis: 1519315624135] [levelValue: 1000] [[ Exception while loading the app : EJB Container initialization error java.lang.RuntimeException: Could not invoke defineClass!

I uploaded the server log here: https://pastebin.com/cB0EgG4Y

UserDao

@Stateless
class UserDao : Abstract<User>() {
    override fun getEntityClass(): Class<User> {
        return User::class.java
    }
}

Abstract Dao

@Stateless
abstract class Abstract<T : Model> {
    @PersistenceContext(unitName = "kwetter")
    private lateinit var entityManager: EntityManager

    abstract fun getEntityClass(): Class<T>

    fun find(id: Int): T {
        return entityManager.find(getEntityClass(), id)
    }
}

Service

@Stateless
class UserService {
    @Inject private var userDao: UserDao? = null

    fun find(id: Int): User {
        return userDao!!.find(id)
    }
}

API endpoint

@Stateless
@Named
@Path("/users")
class Users {
    @Inject private var userService: UserService? = null

    @GET
    @Path("/{id}")
    @Produces("application/json")
    fun single(@PathParam("id") id: Int): User {
        return userService!!.find(id)
    }
}

Mike Mike · Accepted Answer · 2018-02-22T21:01:40

In Kotlin, all classes are implicitly final by default, hence this error in your logs:

Caused by: java.lang.VerifyError: Cannot inherit from final class at java.lang.ClassLoader.defineClass1(Native Method) at java.lang.ClassLoader.defineClass(ClassLoader.java:763)

Mark your classes as open if you want to extend them:

The open annotation on a class is the opposite of Java's final: it allows others to inherit from this class. By default, all classes in Kotlin are final, which corresponds to Effective Java, Item 17: Design and document for inheritance or else prohibit it.

https://kotlinlang.org/docs/reference/classes.html#inheritance

EJB Container initialization error, could not invoke defineClass

2 Answers