Java: note that classes with entirely private constructors can't be subclassed - #20560
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smowton merged 1 commit intoOct 1, 2025
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Pull Request Overview
This PR fixes a false positive in the StartInConstructor query by recognizing that classes with only private constructors cannot be subclassed, making thread starts in their constructors safe.
Key changes:
- Adds logic to detect classes with entirely private constructors
- Updates the cannotBeExtended predicate to include this case
- Adds a test case demonstrating the fix
Reviewed Changes
Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.
| File | Description |
|---|---|
| java/ql/src/Likely Bugs/Concurrency/StartInConstructor.ql | Enhanced query logic to recognize classes with all-private constructors as non-extendable |
| java/ql/test/query-tests/StartInConstructor/Test.java | Added test case for class with private constructors that starts a thread |
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java/ql/src/Likely Bugs/Concurrency/StartInConstructor.ql
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September 30, 2025 12:57
aschackmull
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Oct 1, 2025
aschackmull
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LGTM
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Quick drive-by FP fix found while triaging autofixes.