I'm struggling with this exception for a while already. A relevant thread on the firebase group is kind of dead https://groups.google.com/forum/#!topic/firebase-talk/iy0762S3KsU, also two related on SO are unanswered: Uncaught exception in Firebase runloop (3.0.0) and Uncaught exception in Firebase runloop (3.0.0). Please report to support@firebase.com
The workaround saying to switch off database persistence works, but it's not unacceptable for apps which require offline capability.
I've prepared a minimal activity example which reproduces the exception in my environment. It all comes down to reading the database with queries. It's enough to launch and terminate ("terminate" from Android Studio, not just quit) the activity 3 times (weird) and on the 3rd launch it will crash with the following spectacular series of exceptions (the more queries queued the more exceptions i think):
07-05 18:47:10.132 20291-20291/com.mypackage D/ChimeraFileApk: Classloading successful. Optimized code found.
07-05 18:47:10.154 20291-20381/com.mypackage E/RunLoop: Uncaught exception in Firebase runloop (3.0.0). Please report to support@firebase.com
java.lang.AssertionError: hardAssert failed:
at com.google.android.gms.internal.zzaiv.zzb(Unknown Source)
at com.google.android.gms.internal.zzaiv.zzaN(Unknown Source)
at com.google.android.gms.internal.zzagh.zzb(Unknown Source)
at com.google.android.gms.internal.zzagh.<init>(Unknown Source)
at com.google.android.gms.internal.zzaga.<init>(Unknown Source)
at com.google.android.gms.internal.zzaga.<init>(Unknown Source)
at com.google.android.gms.internal.zzadp.zza(Unknown Source)
at com.google.android.gms.internal.zzaeu.zzic(Unknown Source)
at com.google.android.gms.internal.zzafc.zzRy(Unknown Source)
at com.google.android.gms.internal.zzafc.zza(Unknown Source)
at com.google.android.gms.internal.zzafc$1.run(Unknown Source)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:423)
at java.util.concurrent.FutureTask.run(FutureTask.java:237)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:269)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1113)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:588)
at java.lang.Thread.run(Thread.java:818)
07-05 18:47:10.154 20291-20291/com.mypackage D/AndroidRuntime: Shutting down VM
07-05 18:47:10.155 20291-20291/com.mypackage E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.mypackage, PID: 20291
java.lang.RuntimeException: Uncaught exception in Firebase runloop (3.0.0). Please report to support@firebase.com
at com.google.android.gms.internal.zzadp$1$1.run(Unknown Source)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:148)
at android.app.ActivityThread.main(ActivityThread.java:5417)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)
Caused by: java.lang.AssertionError: hardAssert failed:
at com.google.android.gms.internal.zzaiv.zzb(Unknown Source)
at com.google.android.gms.internal.zzaiv.zzaN(Unknown Source)
at com.google.android.gms.internal.zzagh.zzb(Unknown Source)
at com.google.android.gms.internal.zzagh.<init>(Unknown Source)
at com.google.android.gms.internal.zzaga.<init>(Unknown Source)
at com.google.android.gms.internal.zzaga.<init>(Unknown Source)
at com.google.android.gms.internal.zzadp.zza(Unknown Source)
at com.google.android.gms.internal.zzaeu.zzic(Unknown Source)
at com.google.android.gms.internal.zzafc.zzRy(Unknown Source)
at com.google.android.gms.internal.zzafc.zza(Unknown Source)
at com.google.android.gms.internal.zzafc$1.run(Unknown Source)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:423)
at java.util.concurrent.FutureTask.run(FutureTask.java:237)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:269)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1113)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:588)
at java.lang.Thread.run(Thread.java:818)
07-05 18:47:10.165 20291-20381/com.mypackage E/RunLoop: Uncaught exception in Firebase runloop (3.0.0). Please report to support@firebase.com
java.lang.NullPointerException: Attempt to invoke virtual method 'java.util.List com.google.android.gms.internal.zzafj.zzg(com.google.android.gms.internal.zzaew)' on a null object reference
at com.google.android.gms.internal.zzafc.zzf(Unknown Source)
at com.google.firebase.database.Query$3.run(Unknown Source)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:423)
at java.util.concurrent.FutureTask.run(FutureTask.java:237)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:269)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1113)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:588)
at java.lang.Thread.run(Thread.java:818)
07-05 18:47:10.166 20291-20381/com.mypackage E/RunLoop: Uncaught exception in Firebase runloop (3.0.0). Please report to support@firebase.com
java.lang.NullPointerException: Attempt to invoke virtual method 'java.util.List com.google.android.gms.internal.zzafj.zzg(com.google.android.gms.internal.zzaew)' on a null object reference
at com.google.android.gms.internal.zzafc.zzf(Unknown Source)
at com.google.firebase.database.Query$3.run(Unknown Source)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:423)
at java.util.concurrent.FutureTask.run(FutureTask.java:237)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:269)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1113)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:588)
at java.lang.Thread.run(Thread.java:818)
07-05 18:47:10.173 20291-20381/com.mypackage E/RunLoop: Uncaught exception in Firebase runloop (3.0.0). Please report to support@firebase.com
java.lang.NullPointerException: Attempt to invoke virtual method 'void com.google.android.gms.internal.zzafg.zzg(com.google.android.gms.internal.zzafa, com.google.android.gms.internal.zzahu)' on a null object reference
at com.google.android.gms.internal.zzafc.zzb(Unknown Source)
at com.google.android.gms.internal.zzafc.zza(Unknown Source)
at com.google.android.gms.internal.zzafc.zzaO(Unknown Source)
at com.google.firebase.database.connection.idl.IPersistentConnectionImpl$3.zzaO(Unknown Source)
at com.google.firebase.database.connection.idl.zzi$zza.onTransact(Unknown Source)
at android.os.Binder.transact(Binder.java:387)
at alx.a(:com.google.android.gms.DynamiteModulesC:196)
at amb.a(:com.google.android.gms.DynamiteModulesC:330)
at akh.a(:com.google.android.gms.DynamiteModulesC:3591)
at amf.a(:com.google.android.gms.DynamiteModulesC:386)
at aln.onTransact(:com.google.android.gms.DynamiteModulesC:50)
at android.os.Binder.transact(Binder.java:387)
at com.google.firebase.database.connection.idl.zzf$zza$zza.zzhT(Unknown Source)
at com.google.firebase.database.connection.idl.IPersistentConnectionImpl$5$1.zzhT(Unknown Source)
at com.google.android.gms.internal.zzaeu$1$1.zzhT(Unknown Source)
at com.google.android.gms.internal.zzadn$1.onFailure(Unknown Source)
at com.google.android.gms.tasks.zzd$1.run(Unknown Source)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:423)
at java.util.concurrent.FutureTask.run(FutureTask.java:237)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:269)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1113)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:588)
at java.lang.Thread.run(Thread.java:818)
07-05 18:47:11.745 20291-20291/com.mypackage I/Process: Sending signal. PID: 20291 SIG: 9
The crash is on the first attempt to read after getting the reference to the database and setting persistence is done.
Here's the activity:
public class TestRunloopException extends AppCompatActivity {
private static final String TAG = "test";
private Handler mHandler = new Handler();
Runnable mReadScoresRunnable = new Runnable() {
@Override
public void run() {
readScores();
mHandler.postDelayed(mReadScoresRunnable, 5000);
}
};
@Override
protected void onStart() {
super.onStart();
mHandler.postDelayed(mReadScoresRunnable, 3000);
}
void readScores() {
DatabaseReference scoresRef = getDatabase().getReference("scores");
//it occurs even with a single query..
//scoresRef.startAt(51).limitToFirst(3).addListenerForSingleValueEvent(new MyValueListener());
scoresRef.endAt(50).limitToLast(4).addListenerForSingleValueEvent(new MyValueListener());
}
public static class MyValueListener implements ValueEventListener {
@Override
public void onDataChange(DataSnapshot data) {
Log.d(TAG, "onDataChange: " + data.getValue());
}
@Override
public void onCancelled(DatabaseError error) {
Log.d(TAG, "onCancelled: " + error.getMessage());
}
}
// access-wrapper, set persistence only once
private static FirebaseDatabase mDatabase;
public static FirebaseDatabase getDatabase() {
if (mDatabase == null) {
mDatabase = FirebaseDatabase.getInstance();
mDatabase.setPersistenceEnabled(true);
}
return mDatabase;
}
}
The "scores" node has no particular security settings: "scores": { ".read": true, ".write": true } ...
Tested with firebase-*:9.0.2, but the bug has been also observed with 9.2.0.
How to avoid the crash while using multiple queries on the same reference/node and of course having persistence?
