[ARROW-6853] [Java] Support vector and dictionary encoder use different hasher for calculating hashCode

• Type: New Feature
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.16.0
• Component/s: Java
• Labels: pull-request-available
• Assignee: Ji Liu
• Reporter: Ji Liu
• Created: 11/Oct/19 10:31
• Updated: 16/Oct/19 05:20
• Resolved: 16/Oct/19 05:20

Description

Hasher interface was introduce in ARROW-5898 and now have two different implementations (MurmurHasher and SimpleHasher) and it could be more in the future.

And currently ValueVector#hashCode and DictionaryHashTable only use SimpleHasher for calculating hashCode. This issue enables them to use different hasher or even user-defined hasher for their own use cases.

Issue Links

• links to: GitHub Pull Request #5625