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{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Data import methods free memory","articleBody":"The various import methods in the Data class are documented to transfer ownership of the Arrow data from the input object to internal values as per the C FFI. If I'm reading https://arrow.apache.org/docs/format/CDataInterface.html#moving-an-array correctly, implementations are supposed to hollow out the input object in that case by nulling the release field. In practice a class like ArrayImporter does this\n\n```\nvoid importArray(ArrowArray src) {\n  ...\n  // Move imported array\n  ArrowArray ownedArray = ArrowArray.allocateNew(allocator);\n  ownedArray.save(snapshot);\n  src.markReleased();\n  src.close();\n  ...\n}\n```\n\nSo not only is the array marked as released, it is also closed so the ArrowArray instance is no longer usable. This may or may not happen when you call `Data#importIntoVector` for instance, since that might abort early when given a null `Allocator` which makes the post conditions of `Data#importIntoVector` a bit unclear. You kind of expect the ArrowArray to have been closed, but you still need to call close yourself as well or risk having a memory leak.\n\nWhat's the rationale behind the choice to also call `close` on objects passed to Data rather than expecting people to use try-with-resources/try-finally themselves?","author":{"url":"https://github.com/pepijnve","@type":"Person","name":"pepijnve"},"datePublished":"2025-05-22T09:29:29.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":4},"url":"https://github.com/763/arrow-java/issues/763"}