[LUCENE-10251] Add the compliant "Direct" doc-value format

• Type: Improvement
• Status: Open
• Priority: Minor
• Resolution: Unresolved
• Affects Version/s: 10.0 (main)
• Component/s: core/codecs
• Lucene Fields: New, Patch Available
• Review Patch?: Yes
• Assignee: Unassigned
• Reporter: spike liu
• Created: 23/Nov/21 02:00
• Updated: 28/Aug/22 16:30

Description

In an effort to keep the "Direct" doc-value format in future release, we moved them to doc-value iterators. Any review would be appreciated.

Main changes include:

• Use DocValuesIterator instead of LegacyDocValues.java in DirectDocValuesProducer;
• Embed iterator implementation inside DirectDocValuesConsumer for code reuse;
• All test cases have been run successfully and included in pull request;

P.S. Our business scenario:

• Save the inventory in Direct doc-value format;
• Update them in memory with high-frequency without persistence;
• Load inventory from data storage during app ignite;

Issue Links

• fixes: LUCENE-8917 Remove the "Direct" doc-value format
• relates to: LUCENE-10336 DirectDocValueFormat: use RandomAccessSlice instead of loading giant byte[] arrays
• links to: GitHub Pull Request #464