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Debugging Java InterruptedException i.e. finding the cause

During debugging of Android app, sometimes InterruptedException occurs and crashes the app. I've been able to set a break-point on default exception handler, but call stack is not informative.

at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.reportInterruptAfterWait(AbstractQueuedSynchronizer.java:1991)
at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2025)
at java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:1048)
at java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:776)
at java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1035)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1097)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:588)
at java.lang.Thread.run(Thread.java:820)

What is telling is that the interrupted thread is always RxCachedThreadScheduler-4 (or some other number)

What would be a systematic approach towards finding the root cause of the exception?

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clearpath Avatar asked Jul 19 '18 20:07

clearpath


People also ask

What causes InterruptedException in Java?

Class InterruptedException. Thrown when a thread is waiting, sleeping, or otherwise occupied, and the thread is interrupted, either before or during the activity. Occasionally a method may wish to test whether the current thread has been interrupted, and if so, to immediately throw this exception.

Why is InterruptedException a checked exception?

Making the exception checked is an attempt to ensure that the developer knows the exception can be thrown so that the developer can avoid the situation where the exception gets thrown in the middle of work the thread is doing, potentially leaving the work partially-done in a bad state.

Why InterruptedException should not be ignored?

InterruptedExceptions should never be ignored in the code, and simply logging the exception counts in this case as "ignoring". The throwing of the InterruptedException clears the interrupted state of the Thread, so if the exception is not handled properly the information that the thread was interrupted will be lost.


2 Answers

Set breakpoint at the method Thread::interrupt and catch the offender. If you think that this interruption should not happen, and you cannot switch off the call which interrupts your thread, then you can override Thread::interrupt in your thread implementation, and force the the thread pool to use your implementation by providing your own ThreadFactory.

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Alexei Kaigorodov Avatar answered Oct 09 '22 18:10

Alexei Kaigorodov


It looks like the crash is happening from a third party code package, you should post your issue with the source project as well for additional help. Please post any code related to how you use this package to help troubleshoot too. Make sure you're using the latest version of this package in case they already fixed this issue. The stack trace isn't very helpful because the other project is launching threads and the crash happens from within one of their threads. Likely, you're not using the package as intended or there is a bug in it that they need to fix.

https://github.com/ReactiveX/RxJava
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CodeSmith Avatar answered Oct 09 '22 16:10

CodeSmith