[SOLR-8807] NPE during spell checking when result collapsing is activated and index got more than one segment.

• Type: Bug
• Status: Closed
• Priority: Critical
• Resolution: Fixed
• Affects Version/s: 5.4
• Fix Version/s: 6.6, 7.0
• Component/s: spellchecker
• Labels: collapse spellcheck

Environment

Solr 5.4 with an index cosisting of two segments

• Assignee: James Dyer
• Reporter: Christian Danninger
• Created: 09/Mar/16 10:45
• Updated: 08/Jun/17 23:26
• Resolved: 10/Apr/17 14:27

Description

When using spellchecker with collapse/expand results, I got an NPE. Only happend when the index consists of more than one segment.

11:30:33,505 WARN  [org.apache.solr.spelling.SpellCheckCollator] (http-/0.0.0.0:8080-2) Exception trying to re-query to check if a spell check possibility would return any hits.: java.lang.NullPointerException
        at org.apache.solr.search.CollapsingQParserPlugin$OrdScoreCollector.finish(CollapsingQParserPlugin.java:631) [solr-core-5.4.0.jar:5.4.0 1718046 - upayavira - 2015-12-04 23:16:46]
        at org.apache.solr.search.CollapsingQParserPlugin$OrdScoreCollector.finish(CollapsingQParserPlugin.java:681) [solr-core-5.4.0.jar:5.4.0 1718046 - upayavira - 2015-12-04 23:16:46]
        at org.apache.solr.search.SolrIndexSearcher.buildAndRunCollectorChain(SolrIndexSearcher.java:213) [solr-core-5.4.0.jar:5.4.0 1718046 - upayavira - 2015-12-04 23:16:46]
        at org.apache.solr.search.SolrIndexSearcher.getDocListNC(SolrIndexSearcher.java:1672) [solr-core-5.4.0.jar:5.4.0 1718046 - upayavira - 2015-12-04 23:16:46]
        at org.apache.solr.search.SolrIndexSearcher.getDocListC(SolrIndexSearcher.java:1491) [solr-core-5.4.0.jar:5.4.0 1718046 - upayavira - 2015-12-04 23:16:46]
        at org.apache.solr.search.SolrIndexSearcher.search(SolrIndexSearcher.java:557) [solr-core-5.4.0.jar:5.4.0 1718046 - upayavira - 2015-12-04 23:16:46]
        at org.apache.solr.handler.component.QueryComponent.process(QueryComponent.java:525) [solr-core-5.4.0.jar:5.4.0 1718046 - upayavira - 2015-12-04 23:16:46]
        at org.apache.solr.spelling.SpellCheckCollator.collate(SpellCheckCollator.java:147) [solr-core-5.4.0.jar:5.4.0 1718046 - upayavira - 2015-12-04 23:16:46]
        at org.apache.solr.handler.component.SpellCheckComponent.addCollationsToResponse(SpellCheckComponent.java:238) [solr-core-5.4.0.jar:5.4.0 1718046 - upayavira - 2015-12-04 23:16:46]
        at org.apache.solr.handler.component.SpellCheckComponent.process(SpellCheckComponent.java:203) [solr-core-5.4.0.jar:5.4.0 1718046 - upayavira - 2015-12-04 23:16:46]
        at org.apache.solr.handler.component.SearchHandler.handleRequestBody(SearchHandler.java:281) [solr-core-5.4.0.jar:5.4.0 1718046 - upayavira - 2015-12-04 23:16:46]
        at org.apache.solr.handler.RequestHandlerBase.handleRequest(RequestHandlerBase.java:156) [solr-core-5.4.0.jar:5.4.0 1718046 - upayavira - 2015-12-04 23:16:46]
        at org.apache.solr.core.SolrCore.execute(SolrCore.java:2073) [solr-core-5.4.0.jar:5.4.0 1718046 - upayavira - 2015-12-04 23:16:46]

  <requestHandler name="/select" class="solr.SearchHandler">
	<arr name="last-components">
	  <str>spellchecker</str>
	</arr>    
    </requestHandler>

The query parameters are:

      "spellcheck.maxCollations": "5",
      "q.op": "AND",
      "fq": "{!collapse field=type}",
      "spellcheck.maxCollationTries": "10",
      "spellcheck.collateMaxCollectDocs": "100000",
      "spellcheck.alternativeTermCount": "10",
      "spellcheck.extendedResults": "true",
      "spellcheck.dictionary": [
        "dest_wordbreak",
        "dest_fuzzy"
      ],
      "q": "kosamui thailand",
      "defType": "edismax",
      "expand": "true",
      "spellcheck.maxResultsForSuggest": "3",
      "qf": "country_name region_name",
      "spellcheck": "true",
      "spellcheck.accuracy": "0.5",
      "spellcheck.count": "20",
      "spellcheck.collate": "true",

Issue Links

• is duplicated by: SOLR-7754 spellcheck.collate does not work with field collapsing
• relates to: SOLR-9104 NPE in CollapsingQParser when two fq={!collapse} and zero results
• relates to: SOLR-10336 NPE during queryCache warming
• relates to: SOLR-7435 NPE can occur if CollapsingQParserPlugin is used two or more times in the same query