Realm-java: Cannot be cast to io.realm.FooRealmProxyInterface

[ppamorim]

Goal

Simply load data, I'm using Kotlin 1.0.4 and minifyEnabled

Result

ClassCastException when it tries to do a query.

Steps & Code to Reproduce

It happens randomly, the code sample is below.

Code Sample

fun insertOrUpdate(taskQueue: TaskQueue?, realm: Realm?) {
  try {
    realm?.run {
      executeTransaction {
        taskQueue?.let {
          insertOrUpdate(it)
        }
      }
    }
  } catch (e: Exception) {
    if (DEBUG_ENABLED) {
      e.printStackTrace()
    }
    Crashlytics.logException(e)
  }
}

open class TaskQueue(
    @PrimaryKey var id: String,
    var layers: RealmList<Layer> = RealmList()):
    RealmObject(), Parcelable {

  companion object {
    @JvmField val CREATOR = object : Parcelable.Creator<TaskQueue> {
      override fun createFromParcel(source: Parcel) = TaskQueue(source)
      override fun newArray(size: Int): Array<TaskQueue?> = arrayOfNulls(size)
    }
  }
  //...Parcel and more not important
}

Version of Realm and tooling

Realm version(s): 2.2.1
Realm sync feature enabled: No
Android Studio version: 2.1.2 / gradle-2.14.1
Which Android version and device: 6.0 - LG G2

[Zhuinden]

This is not the relevant code sample, the code sample would be when insertOrUpdate is called in a lambda expression.

It sounds like a List is saved in which some objects are managed and some are not.

[beeender]

It looks strange, the TaskQueue (both managed/unmanged) should be able to be cast to TaskQueueRealmProxyInterface always because Realm transformer did it, see addRealmProxyInterface of Realm transformer.

@ppamorim Are you using instant run? https://realm.io/docs/java/latest/#kotlin is any information here useful? Can you reproduce the issue with a minimal project?

[ppamorim]

@Zhuinden I'm doing only that insert, nothing different.
@beeender No, I'm not. I had a lot of problems (the project doesn't compile using Instant run), then it is disabled.

Here is the error:

[altero]

Have the same problem with copyOrUpdate.

I use this approach:

fun cache(realm: Realm): CachedIdRealmObject {
    cacheTransform?.invoke()

    return if (realm.getTable(this.javaClass).hasPrimaryKey())
        realm.copyToRealmOrUpdate(this)
    else realm.copyToRealm(this)
}

CachedIdRealmObject is just an interface, extends RealmModel

Problem remains with top-level models with @PrimaryKey-s and with @PrimaryKey models inside non-@PrimaryKey models.

The problem is at this line:

long rowIndex = table.findFirstLong(pkColumnIndex, ((FileModelInfoRealmProxyInterface) object).realmGet$id());

Kotlin: 1.0.5-3 / plugin: 1.0.6-eap-112
Realm: 2.2.1
AS: 2.3 Beta 1
Gradle: 3.2
Android Gradle plugin: 2.3.0-beta1

[ppamorim]

@altero Are you using Proguard or Minify? If yes, try to disable it for a moment. I'm doing some tests here and I noticed that error is gone when it is disabled.

[altero]

Ok, it seems to work great with

Kotlin: 1.0.5-3 / plugin: 1.0.5-3
Realm: 2.2.1
AS: 2.2
Gradle: 3.2
Android Gradle plugin: 2.2.3

Not sure what actually fixed the build, but anyway.

[altero]

@ppamorim I tried to build with and without proguard. It seems, that proguard was not the problem, coz without proguard I also had this error.

[ppamorim]

@altero False alarm, this error is happening with Proguard disabled, sad. :(

[altero]

Kotlin: 1.0.5-3 / plugin: 1.0.5-3
Realm: 2.2.1
AS: 2.2
Gradle: 3.2
Android Gradle plugin: 2.2.3

Sorry, this doesn't work either, continue to downgrade environment versions...

[Zhuinden]

you apply kotlin-android before realm-android, right?

[altero]

@Zhuinden

apply plugin: 'com.android.application'
apply plugin: 'kotlin-android'
apply plugin: 'kotlin-kapt'
apply plugin: 'realm-android'
apply plugin: 'io.fabric'
apply plugin: 'com.getkeepsafe.dexcount'

Well, I totally forgot. I'm using kapt2

But everything worked until I've updated smth to alpha/canary/eap version.

[ppamorim]

@Zhuinden

apply plugin: 'kotlin-android'
apply plugin: 'kotlin-android-extensions'
apply plugin: 'io.fabric'
apply plugin: 'checkstyle'
apply plugin: 'realm-android'

I'm using kapt2 too.

[Zhuinden]

Do you think you can try kapt instead of kapt2 and see if it surfaces?

Although I see no reason why it wouldn't work.

[altero]

Ok, I found working configuration:

Kotlin: 1.0.5-3 / plugin: 1.0.5-3
Realm: 2.2.1
AS: 2.2
Gradle: 3.1
Android Gradle plugin: 2.2.3

And I remembered, that I had same problems last time I updated Gradle to 3.2. I believe, that the problem is with it and it's now a default for Android Studio 2.3.

[altero]

@Zhuinden it seems, that @ppamorim uses kapt, instead of kapt2. Coz there is no apply plugin: 'kotlin-kapt' in his configuration.

[zaki50]

Does adding @RealmClass annotation to TaskQueue class solve the issue? https://realm.io/docs/java/latest/#kotlin

[ppamorim]

@altero Sorry I'm using kapt2 I just missed the apply plugin hehe
@zaki50 I will check it.

[altero]

@zaki50 doesn't work for me. Still get

java.lang.ClassCastException: pa.ckage.data.models.FileModelInfo cannot be cast to io.realm.FileModelInfoRealmProxyInterface

after adding @RealmClass with Gradle 3.2.
On Gradle 3.1 works ok even without @RealmClass.

[zaki50]

Hmm, I tried to reproduce it on my project, but no success.

https://github.com/zaki50/realm_template/blob/master/kotlin_app/build.gradle
I executed realm.insertOrUpdate() on this project and it completely worked...
Can you see any differences in my project?

[kneth]

I'm closing for now. If you are able to spot any differences between your project and @zaki50's project, please tell us to reopen.

[consp1racy]

@kneth What about this?

gradle.properties

org.gradle.parallel=true

App module A depends on Library module B. Both have Realm classes, both apply the Realm plugin.

Realm 3.0.0, Kotlin 1.1.1 with kapt2/3, kotlin.incremental=false.

[kneth]

Maybe @zaki50 can try to various combinations of those flags?

[stipundzya]

Had the same problem. It was solved by 3 steps: 1. Clean the project 2. Clear app data/cache 3.Uninstall/install app

[SiarheiSm]

Hello. Had the same problem: https://stackoverflow.com/questions/52361444/realm-crashes-on-get-data-after-added-kotlin-support