[LUCENE-6066] Collector that manages diversity in search results

• Type: Improvement
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 5.1
• Component/s: core/query/scoring
• Lucene Fields: New
• Assignee: Unassigned
• Reporter: Mark Harwood
• Created: 20/Nov/14 16:26
• Updated: 28/Aug/22 14:19
• Resolved: 12/Feb/15 10:13

Description

This issue provides a new collector for situations where a client doesn't want more than N matches for any given key (e.g. no more than 5 products from any one retailer in a marketplace). In these circumstances a document that was previously thought of as competitive during collection has to be removed from the final PQ and replaced with another doc (eg a retailer who already has 5 matches in the PQ receives a 6th match which is better than his previous ones). This requires a new remove method on the existing PriorityQueue class.