Crash in my app

[UrielFrankel]

Here is the stack trace:

java.util.concurrent.RejectedExecutionException: Task java.util.concurrent.FutureTask@651c9a5[Not completed] rejected from java.util.concurrent.ThreadPoolExecutor@6e1517a[Shutting down, pool size = 1, active threads = 1, queued tasks = 2, completed tasks = 1]
	at java.util.concurrent.ThreadPoolExecutor$AbortPolicy.rejectedExecution(ThreadPoolExecutor.java:2072)
	at java.util.concurrent.ThreadPoolExecutor.reject(ThreadPoolExecutor.java:834)
	at java.util.concurrent.ThreadPoolExecutor.execute(ThreadPoolExecutor.java:1364)
	at java.util.concurrent.AbstractExecutorService.submit(AbstractExecutorService.java:118)
	at java.util.concurrent.Executors$DelegatedExecutorService.submit(Executors.java:671)
	at io.github.centrifugal.centrifuge.Client$1.onClosed(SourceFile:15)
	at okhttp3.internal.ws.RealWebSocket.writeOneFrame$okhttp(SourceFile:188)
	at okhttp3.internal.ws.RealWebSocket$WriterTask.runOnce(SourceFile:3)
	at okhttp3.internal.concurrent.TaskRunner.runTask(SourceFile:63)
	at okhttp3.internal.concurrent.TaskRunner.access$runTask(Unknown Source:0)
	at okhttp3.internal.concurrent.TaskRunner$runnable$1.run(SourceFile:55)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1137)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:637)
	at java.lang.Thread.run(Thread.java:1012)

I have zero clue what happen. As you can see I can't even guard it with try/catch. I called unsubscribe() and then close(). Is that the problem? Should I put the close() in the onDestroy of the App? thanks.

[FZambia]

Hello @UrielFrankel - seems that you can easily reproduce this? Can you provide example code?

[UrielFrankel]

I can't reproduce it but I can send you what I do:

fun disconnect() {
    unsubscribe()
    Logger.d(TAG, "disconnect() called")
    try {
        client?.close(5000) // from demo app
        client = null
    } catch (e: InterruptedException) {
        Logger.e(TAG, "error in centrifugo disconnection ", e)
    }
    this.connectionId = null
}

fun unsubscribe() {
    Logger.d(TAG, "unsubscribe() called")
    currentSubscription?.let {
        client?.removeSubscription(it)
        currentSubscription = null
    }
}

I suspect that calling removeSubscription and immediately close is the problem.

[FZambia]

Thanks, I'll experiment - in general you need to call Close when you don't need client anymore. After calling Close client is unusable.

But in this case I suppose onClosed callback of WebSocket is called after ThreadPoolExecutor already closed. We already handle RejectedExecutionException in OnFailure -

centrifuge-java/centrifuge/src/main/java/io/github/centrifugal/centrifuge/Client.java

Line 378 in f11c20c

} catch (RejectedExecutionException ignored) {

, but for some reason not handling it in other WebSocket callbacks - like the one in your stacktrace (onClosed).

[UrielFrankel]

Good news, I was able to reproduce it in my app. I called for close before i was fully connected and close calls disconnect.

[FZambia]

Reproduced locally and opened #71

[FZambia]

The fix is shipped in 0.3.1