[HBASE-6907] KeyValue equals and compareTo methods should match

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.95.0
• Component/s: util
• Hadoop Flags: Reviewed

Release Note

KeyValue.equals() method used to ignore the memstoreTS.
Now KeyValue.equals() takes memstoreTS into account and is aligned with KeyValue.KVComparator in behavior

• Assignee: Ted Yu
• Reporter: Matt Corgan
• Created: 01/Oct/12 17:36
• Updated: 23/Sep/13 18:31
• Resolved: 21/Jan/13 21:53

Description

KeyValue.KVComparator includes the memstoreTS when comparing, however the KeyValue.equals() method ignores the memstoreTS.

The Comparator interface has always specified that comparator return 0 when equals would return true and vice versa. Obeying that rule has been sort of optional in the past, but Java 7 introduces a new default collection sorting algorithm called Tim Sort which relies on that behavior. http://bugs.sun.com/view_bug.do?bug_id=6804124

Possible problem spots:

• there's a Collections.sort(KeyValues) in RedundantKVGenerator.generateTestKeyValues(..)
• TestColumnSeeking compares two collections of KeyValues using the containsAll method. It is intentionally ignoring memstoreTS, so will need an alternative method for comparing the two collections.

Issue Links

• relates to: HBASE-4676 Prefix Compression - Trie data block encoding