[LUCENE-8564] Make it easier to iterate over graphs in tokenstreams

• Type: Task
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 8.0
• Lucene Fields: New
• Assignee: Alan Woodward
• Reporter: Alan Woodward
• Created: 13/Nov/18 10:30
• Updated: 28/Aug/22 15:37
• Resolved: 04/Dec/18 10:04

Description

We have a number of TokenFilters that read ahead in the token stream (eg synonyms, shingles) and ideally these would understand token graphs as well as linear streams. FixedShingleFilter already has some mechanisms to deal with graphs; this issue is to extract this logic into a GraphTokenStream class that can then be reused by other token filters