NPE in 'android.media.session.ISession.getController()'

[deepanshu-hh]

I've noticed this log in my crashlytics:

 Caused by java.lang.NullPointerException
Attempt to invoke interface method 'android.media.session.ISessionController android.media.session.ISession.getController()' on a null object reference
android.media.session.MediaSession.<init> (MediaSession.java:199)
android.media.session.MediaSession.<init> (MediaSession.java:156)
android.support.v4.media.session.MediaSessionCompatApi21.createSession (MediaSessionCompatApi21.java:46)
android.support.v4.media.session.MediaSessionCompat$MediaSessionImplApi21.<init> (MediaSessionCompat.java:3380)
android.support.v4.media.session.MediaSessionCompat$MediaSessionImplApi28.<init> (MediaSessionCompat.java:3906)
android.support.v4.media.session.MediaSessionCompat.<init> (MediaSessionCompat.java:493)
android.support.v4.media.session.MediaSessionCompat.<init> (MediaSessionCompat.java:456)
android.support.v4.media.session.MediaSessionCompat.<init> (MediaSessionCompat.java:430)
com.hh.exoplayer.HHPlayerService$CustomPlayerNotificationManager.<init> (HHPlayerService.java:498)
com.hh.exoplayer.HHPlayerService$1.<init> (HHPlayerService.java:124)
com.hh.exoplayer.HHPlayerService.createNotification (HHPlayerService.java:123)
com.hh.exoplayer.HHPlayerService.onCreate (HHPlayerService.java:111)
android.app.ActivityThread.handleCreateService (ActivityThread.java:4379)
android.app.ActivityThread.access$1900 (ActivityThread.java:274)
android.app.ActivityThread$H.handleMessage (ActivityThread.java:2112)
android.os.Handler.dispatchMessage (Handler.java:106)
android.os.Looper.loop (Looper.java:233)
android.app.ActivityThread.main (ActivityThread.java:8010)
java.lang.reflect.Method.invoke (Method.java)
com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run (RuntimeInit.java:631)
com.android.internal.os.ZygoteInit.main (ZygoteInit.java:978) 

When trying create Audio notification style within my AudioService (an Android Service which plays audio files).

I'm building that notification in this way:

            MediaSessionCompat mediaSession = new MediaSessionCompat(context, context.getString(R.string.app_name));
            mediaSession.setActive(true);
            mediaSessionConnector = new MediaSessionConnector(mediaSession);

I'm not being able to replicate it because in every test I do I can play audios and notification is visible (and AudioService has been created successfully).

What's wrong in my code? What is the right way to prevent this and play audios within a Services in versions above API 21?

Thanks in advance!

• ExoPlayer version number - 2.9.6
• Android version - 11
• Android device - 50% samsung devices

[Samrobbo]

@SungsooLim Hey, this is related to Session, can you take a look, or pass it on to the correct person? Thanks.

[enginegl]

We have the same issue, but I'm mot sure if this is related to ExoPlayer

[enginegl]

After some investigation we found out that the cause of this issue is an internal Android MediaSessions limit (100 sessions).
And as I wrote before, this issue is not related to ExoPlayer and can be closed.

How to reproduce
Just create 100 instances of MediaSession:

GlobalScope.launch {
    repeat(200) {
        val session = MediaSessionCompat(context, "Session") // Will cause a crash after 99 iterations
        delay(200)
    }
}

How to fix
You should release MediaSession instances that you don't need anymore.

GlobalScope.launch {
    repeat(200) {
        val session = MediaSessionCompat(context, "Session")
        delay(200)
        session.release()
    }
}

Thanks to the article https://www.codeleading.com/article/71386122411/