*Hi Apache IoTDB community,* PR: https://github.com/apache/iotdb/pull/17810
I have addressed the latest Copilot review comments on PR #17810. The changes include: 1. Added an explicit null check for `FillPolicy fillMethod` in the `Fill` constructor, using `requireNonNull(fillMethod, "fillMethod is null")`, so invalid null input now fails with a clear message before the fill policy comparison. 2. Removed the redundant `groupSplitter` state from `TableNextFillWithGroupOperator`, including its field, constructor initialization, and add/remove bookkeeping. The grouped NEXT fill reset logic remains based on `noMoreTsBlockForCurrentGroup`, so the existing behavior is preserved. *Validation:* `mvn test -pl iotdb-core/datanode -am -Dtest=NextFillTest -DfailIfNoTests=false -Dsurefire.failIfNoSpecifiedTests=false -DskipITs` *Result:Tests run: 5, Failures: 0, Errors: 0, Skipped: 0`BUILD SUCCESS`* Best, Bryan Yang (杨易达)
