[LUCENE-8610] NPE in TermsHashPerField.add() for TokenStreams with lazily instantiated token Attributes

• Type: Wish
• Status: Resolved
• Priority: Minor
• Resolution: Not A Bug
• Affects Version/s: 7.4, 8.0
• Component/s: core/index
• Assignee: Unassigned
• Reporter: Michael Gibney
• Created: 14/Dec/18 17:18
• Updated: 28/Aug/22 15:39
• Resolved: 17/Dec/18 20:14

Description

DefaultIndexingChain.invert(...) calls invertState.setAttributeSource(stream) before stream.incrementToken() is called.

For instances of stream that lazily instantiate token attributes (e.g., as solr.PreAnalyzedField$PreAnalyzedTokenizer does upon the first call to incrementToken() that returns true), this can result in caching a null value in invertState.termAttribute for a given stream instance.

Subsequent calls that reuse the same stream instance (reusing TokenStreamComponents) for field values with at least 1 token will call termHashPerField.start(...) which sets termsHashPerField.termAtt from the null value cached in the FieldInvertState.termAttribute. An NPE would be thrown when termsHashPerField.add() reasonably but incorrectly assumes a non-null value for termAtt.

Issue Links

• is superceded by: SOLR-13077 PreAnalyzedField TokenStreamComponents should be reusable