René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"CursorIterable/KeyRange broken in v0.9.0","articleBody":"The changes in v0.9.0 have broken CursorIterable for some KeyRange types and keys.  I noticed the problem when using `KeyRange.atLeastBackward(`.  The cursor was starting on the wrong key.\r\n\r\nI think the problem is this line:\r\n\r\nhttps://github.com/lmdbjava/lmdbjava/compare/lmdbjava-0.8.3...lmdbjava-0.9.0#diff-a5dda1cdb60b45d45a5a4364768ad1f7c62ac0ec025f295f78d489cf08392bf2R206\r\n\r\nIt is using the standard java `ByteBuffer.compareTo` method rather than your lexographical `AbstractByteBufferProxy::compareBuff` method, so 150 is considered \u003c 110.\r\n\r\nSee my branch (on the link below) where I have changed your `CursorIterableTest` to use 200 ... 900 instead of 2 ... 9 for the key values to demonstrate the problem.  With the modified values a lot of the tests fail.  Changing `AbstractByteBufferProxy` to use `compareBuf` makes them all pass again.\r\n\r\nhttps://github.com/lmdbjava/lmdbjava/compare/master...at055612:backwards-at-least?expand=1\r\n\r\nI think this is the problem is in `AbstractByteBufferProxy`.\r\n```java\r\n    @Override\r\n    protected Comparator\u003cByteBuffer\u003e getComparator(final DbiFlags... flags) {\r\n      final int flagInt = mask(flags);\r\n      if (isSet(flagInt, MDB_INTEGERKEY)) {\r\n        return this::compareCustom;\r\n      }\r\n      return this::compareDefault;\r\n      // TODO Think the above line should be changed to this:\r\n      // return AbstractByteBufferProxy::compareBuff;\r\n    }\r\n```\r\n\r\nIt may also be an issue for netty/agrona but I am not using those so have not looked.\r\n\r\nThis is a pretty serious bug for anyone using KeyRanges and it will present in subtle ways depending on the keys in the db and the keyRange type used.","author":{"url":"https://github.com/at055612","@type":"Person","name":"at055612"},"datePublished":"2023-12-11T13:44:00.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":2},"url":"https://github.com/228/lmdbjava/issues/228"}