Arrow: Document NullabilityHolder.reset() null-marker contract#17252
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thswlsqls wants to merge 1 commit into
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Arrow: Document NullabilityHolder.reset() null-marker contract#17252thswlsqls wants to merge 1 commit into
thswlsqls wants to merge 1 commit into
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reset() clears only the null count and intentionally leaves the isNull marker array as-is. Writers repopulate every index of each batch before the markers are read, so stale values are overwritten rather than observed. Document this so the behavior is not mistaken for a bug. Generated-by: Claude Code
ldudas-marx
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Jul 16, 2026
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| * <p>Only the null count is cleared. The per-index markers returned by {@link #isNullAt(int)} are | ||
| * deliberately left untouched: for every batch, writers set the marker of each index through | ||
| * {@link #setNull(int)}/{@link #setNotNull(int)} (or their bulk variants {@link #setNulls(int, | ||
| * int)}/{@link #setNotNulls(int, int)}) before the markers are read, so values carried over from | ||
| * a previous batch are overwritten rather than observed. |
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I would put these into the function body as comments because it contains implementation details and insights. It targets developers who want to change this class and not the users who want to use this class.
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Documents the behavior reported in #15808
Summary
NullabilityHolder.reset()clears onlynumNulls; theisNullmarker array read byisNullAt(int)is left as-is.VectorizedParquetDefinitionLevelReadersets the marker of each index viasetNull/setNotNull(or the bulksetNulls/setNotNulls) before any marker is read, so values from a previous batch are overwritten rather than observed.reset()stating this contract, so the behavior is not mistaken for a stale-state bug.reset().Testing done
./gradlew :iceberg-arrow:spotlessCheck— passed../gradlew :iceberg-arrow:checkstyleMain— passed.