[FLUSS-1855][server] Add Null Safety for TimerTaskEntry Removal #1872
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[server] Added test to reproduce NPE during TimerTaskEntry removal [server] Added test to reproduce NPE during TimerTaskEntry removal
[server] Added Safety Check for TimerTaskEntry Removal to Avoid NPE
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Purpose
Linked Issue: Close #1855
Per Issue #1855, this pull request addresses a potential issue that could arise during the
remove()operation forTimerTaskEntrythat could result in a null pointer exception being thrown. This was possible as the underlying object to support the internal list was volatile and subject to operations from other threads.Brief change log
Update the logic within the
TimerTaskEntry.remove()operation to use a more concurrency-safe single-read snapshot pattern to avoid separate reads (e.g., reading during iteration and within the body as well). These changes were originally reproduced via a newly added unit test and retained to ensure the issue was resolved as expected.Tests
Added a new
TimerTaskEntryTestclass along with an associatedTimerTaskEntryTest.testRemoveEnsuresCurrentListNullSafetycase that originally reproduced this issue (via concurrent, oscillating add/removals across separate threads) which was eventually updated after the fix was applied to confirm the exception will no longer be thrown.API and Format
N/A
Documentation
N/A