[LUCENE-7342] WordDelimiterFilter should observe KeywordAttribute to pass these tokens through

• Type: Improvement
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Component/s: modules/analysis
• Lucene Fields: New
• Assignee: Unassigned
• Reporter: David Smiley
• Created: 16/Jun/16 19:40
• Updated: 28/Aug/22 14:59

Description

I have a text analysis requirement in which I want certain tokens to not be processed by WordDelimiterFilter – i.e. they should pass through that filter. WDF, like several other TokenFilters, has a configurable word list but this list is static producing a concrete CharArraySet. Thus, for example, I can't filter by a regexp nor can I filter based on other attributes.

A simple solution that makes sense to me is to have WDF use KeywordAttribute to know if it should skip the token. KeywordAttribute seems fairly generic as to how it can be used, although granted today it's only used by the stemmers. That attribute isn't named "StemmerIgnoreAttribute" or some-such; it's generic so I think it's fine for WDF to use it in a similar way.