ChrisAHolland opened a new pull request, #15507: URL: https://github.com/apache/kafka/pull/15507
I noticed that were were a few implementation quirks with the implementation of `BoundedList.java` that could potentially lead to bugs if used improperly. 1. A constructor like method with signature `newArrayBacked(int maxLength, int initialCapacity)` took in two integers, one for the maximum length of the `BoundedList`, and a second for the initial capacity of the underlying `ArrayList`. This seems like a flaw to me because when ArrayLists resize it is a O(n) operation, so if the initial capacity was "under-provisioned" compared to the maximum capacity, many resizing operations could take place as this list grows, which is not good for performance. Fix: Remove `newArrayBacked(int maxLength, int initialCapacity)` and use the new constructor instead (mentioned below). 2. The public constructor had a signature of `public BoundedList(int maxLength, List<E> underlying)`. This is problematic because the the constructor created the `BoundedList` using a reference to `underlying`, not a copy of it; therefore, a user could add elements to `underlying` instead of their newly instantiated `BoundedList` and force the `BoundedList` to be larger than its maxLength`. Fix: Change the constructor to have signature `public BoundedList(int maxLength)`. I noticed that passing in a "original list" was only used in unit tests, never in the source code, but I felt that made the unit tests confusing. If this use case is ever needed, it can be added in again later on. 3. Remaining changes involve updating the usages of `BoundedList` and cleaning up the unit tests. ### Committer Checklist (excluded from commit message) - [ ] Verify design and implementation - [ ] Verify test coverage and CI build status - [ ] Verify documentation (including upgrade notes) -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: jira-unsubscr...@kafka.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org
