Solr 9.4 - Switching _default configset to classic schema issue

[Dominique Bejean]

Hi,

I created a default-classic configset by :
* copying the _default configset
* rename managed-schema.xml file to schema.xml
* add   <schemaFactory class="ClassicIndexSchemaFactory"/> declaration in
solrconfig.xml

I can successfully create a collection
When I test a query analysis in Admin UI with the field type "text
general", the following error occurs

2023-11-09 23:04:10.320 INFO  (qtp1677458155-33) [c:boamp s:shard1
r:core_node5 x:boamp_shard1_replica_n2] o.a.s.c.S.Request webapp=/solr
path=/analysis/field params={analysis.fieldvalue=the
dog&analysis.showmatch=true&verbose_output=1&wt=json&_=1699571050222&analysis.fieldtype=text_general}
status=500 QTime=0
2023-11-09 23:04:10.320 ERROR (qtp1677458155-33) [c:boamp s:shard1
r:core_node5 x:boamp_shard1_replica_n2] o.a.s.s.HttpSolrCall 500 Exception
=> java.lang.NullPointerException: stopWords
   at java.base/java.util.Objects.requireNonNull(Unknown Source)
java.lang.NullPointerException: stopWords
   at java.util.Objects.requireNonNull(Unknown Source) ~[?:?]
   at org.apache.lucene.analysis.StopFilter.<init>(StopFilter.java:39)
~[?:?]
   at org.apache.lucene.analysis.core.StopFilter.<init>(StopFilter.java:43)
~[?:?]
   at
org.apache.lucene.analysis.core.StopFilterFactory.create(StopFilterFactory.java:91)
~[?:?]
   at
org.apache.solr.handler.AnalysisRequestHandlerBase.analyzeValue(AnalysisRequestHandlerBase.java:141)
~[?:?]
   at
org.apache.solr.handler.FieldAnalysisRequestHandler.analyzeValues(FieldAnalysisRequestHandler.java:229)
~[?:?]
   at
org.apache.solr.handler.FieldAnalysisRequestHandler.handleAnalysisRequest(FieldAnalysisRequestHandler.java:186)
~[?:?]
   at
org.apache.solr.handler.FieldAnalysisRequestHandler.doAnalysis(FieldAnalysisRequestHandler.java:103)
~[?:?]
   ...

Same issue with a filter like "elision"

2023-11-09 23:15:31.143 ERROR (qtp1677458155-33) [c:boamp s:shard1
r:core_node5 x:boamp_shard1_replica_n2] o.a.s.s.HttpSolrCall 500 Exception
=> java.lang.NullPointerException: articles
   at java.base/java.util.Objects.requireNonNull(Unknown Source)
java.lang.NullPointerException: articles
   at java.util.Objects.requireNonNull(Unknown Source) ~[?:?]
   at
org.apache.lucene.analysis.util.ElisionFilter.<init>(ElisionFilter.java:44)
~[?:?]
   at
org.apache.lucene.analysis.util.ElisionFilterFactory.create(ElisionFilterFactory.java:79)
~[?:?]

It looks like resource files are not correctly loaded with
ClassicIndexSchemaFactory enabled with Solr 9.4 (with solr 9.3 too).

It works perfectly with Solr 8.11.2

Any suggestions ?

Regards

Dominique