IndexReaderFactory for Lucene [LUCENE-3498]

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An IndexReaderFactory can be used by IndexWriter and DirectoryReader to enable subclasses of DR to be instantiated by Lucene, automatically.

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Migrated from LUCENE-3498 by Jason Rutherglen, updated Oct 10 2011
Attachments: LUCENE-3498.patch (versions: 4)

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Jason Rutherglen (migrated from JIRA)

Here's a first cut and all tests pass!

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Jason Rutherglen (migrated from JIRA)

I think the Solr one could be made better, by passing in the core that's creating it. In that regard, Solr's can be improved rather than nuked.

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Simon Willnauer (@s1monw) (migrated from JIRA)

Instead of adding this factory can't we have a protected DirectoryReader create(..) method in IndexWriter you can override if you really need this. This is way way expert so I don't expect a lot of people use this feature. to open a reader you can then add some static factories in your own code?

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Jason Rutherglen (migrated from JIRA)

Simon, I think you'd be surprised at how many of the current [uber-complex] features of Lucene, few people use (readerTermsIndexDivisor, termIndexInterval, mergedSegmentWarmer are great examples, that are not-so-complex in IWC alone). For people who use this, the factory system is a lot more user friendly than subclassing.

A protected method in IW doesn't take into account opening a DR from a DR, to do that please commit #4571. If that gets in, we can open an issue to add a protected method to IW.

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Robert Muir (@rmuir) (migrated from JIRA)

(readerTermsIndexDivisor, termIndexInterval,

This stuff needs to die, it only makes sense for specific codecs.

For example, I'm pretty sure neither divisor nor interval make sense for the default terms implementation in trunk.

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Jason Rutherglen (migrated from JIRA)

Added support for attaching the new Lucene IndexReaderFactory to a Solr index at the solrconfig.xml level. All tests pass.

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Jason Rutherglen (migrated from JIRA)

Also, the patch is against 3.x.

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Jason Rutherglen (migrated from JIRA)

The current Solr IndexReaderFactory can be deprecated and / or replaced with one that accepts a Solr core.

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Jason Rutherglen (migrated from JIRA)

Added a new [backwards compatibility] SolrIndexReaderFactory that accepts a Solr core as a parameter.

All tests pass.

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Jason Rutherglen (migrated from JIRA)

Removed SolrIndexReaderFactory, instead SolrCoreAware is used for the exact same purpose.

Nice.