Hello. I have this class: <https://gist.github.com/mel4tonin4/a8255ea412dd3f5787deefac27afce4a> It's...

# serialization

[melatonina]

Hello.
I have this class: https://gist.github.com/mel4tonin4/a8255ea412dd3f5787deefac27afce4a
It's compiled just fine in Android Studio, as part of the Android application project, but when I compile it in IDEA, as part of the supporting service project, it fails with the error "@Serializable annotation is ignored because it is impossible to serialize automatically interfaces or enums. Provide serializer manually via e.g.companion object" for both the object's.
In both cases I'm using kotlinx_serialization_runtime_version=0.14.0
In both cases the serialization plugin is selected with classpath "org.jetbrains.kotlin:kotlin-serialization:$kotlin_version" in the top level build.gradle file where kotlin_version=1.3.71
This is the build.gradle of the module that contains the class above: https://gist.github.com/mel4tonin4/9bf05d82f8901613b131998162250495
What's the reason for this difference?

[turansky]

Possible root cause:
• Terminated must be sealed
• Terminated must have @Serializable annotation

[melatonina]

The Started object causes an error, too, but it's not derived by Terminated.
In any case, why doesn't that happen when I build in Android Studio?

[melatonina]

I just tryed, removing the class Terminated doesn't fix the issue.

[turansky]

You need runtime 0.20.0

[turansky]

Android Studio plugin include this version and it works

[turansky]

You use incompatible version. Kotlin 1.3.70 require runtime 0.20.0

[turansky]

https://github.com/kotlin/kotlinx.serialization#incompatible-changes

[melatonina]

Thanks, Victor! I found the same document few hours ago. I already updated my code.
Currently the Android application builds and runs. The supporting service builds but fails at runtime with: "Exception in thread "main" java.lang.NoSuchMethodError: 'void kotlinx.serialization.internal.SerialClassDescImpl.<init>(java.lang.String, kotlinx.serialization.internal.GeneratedSerializer)'"

[melatonina]

I still don't understand why these differences emerged today with serialization. I never had problems on both platforms.

[turansky]

Do you use _SerialClassDescImpl_ in your code?

[turansky]

Possibly you have dependencies, which use previous serialization runtime

[melatonina]

I'll check that. Thanks for the suggestion, Victor!

[melatonina]

This is the list of the the jar files in the classpath of my supporting service application: https://gist.github.com/mel4tonin4/2ae736602b8b999f5406350c4c285370
The kotlinx-serialization is at line 159. It's version 0.20.0 and there are no other version of that jar.
Moreover, this is the exception with stack trace: https://gist.github.com/mel4tonin4/7376c34a9c54f0c4f2aa594dda872ad1
As you can see the exception is thrown while running deserialization code generated for my own classes. The application is trying to de-serialize its configuration file.

[melatonina]

Also, querying a classloader for the URL for the class SerialClassDescImpl at runtime, gives, correctly:
jarfile/[...]/service/jars/kotlinx-serialization-runtime-0.20.0.jar!/kotlinx/serialization/internal/SerialClassDescImpl.class

[turansky]

Class is internal since 0.20.0

[melatonina]

It's used in the generated code, not in mine.
Is the generated code allowed to use it?
Does it mean that an older compiler is being called to generate the serializers?

[melatonina]

The plugin version is selected in the top level guild.gradle file with: classpath "org.jetbrains.kotlin:kotlin-serialization:$kotlin_version"
where kotlin_version=1.3.71.

[melatonina]

In fact, if I apply

plugins { 
id 'org.jetbrains.kotlin.plugin.serialization' version '1.3.71'
}

in the offending module, I get: Error resolving plugin [id: 'org.jetbrains.kotlin.plugin.serialization', version: '1.3.71']

Plugin request for plugin already on the classpath must not include a version

[melatonina]

And using 1.3.70, just in case, doesn't change anything.

[melatonina]

As described in https://github.com/Kotlin/kotlinx.serialization/issues/736#issuecomment-600485633 my buildSrc/build.gradle was outdated and loaded the plugin before anything else, so it set the plugin version.

[melatonina]

Now the problem with my code is fixed. The problems are with ktor.

[melatonina]

Thanks for helping me, @turansky!

[melatonina]

Updating ktor to 1.3.2 fixed the problem with ktor-serialization, too.

[turansky]

Sync required for all depencies
Different Kotlin versions - typical problem for serialization