languagetool-org/languagetool · error · RuntimeException

Could not create query for rule + rule.getId()

Error message

Could not create query for rule + rule.getId()

What it means

Search-index guard: PatternRuleQueryBuilder could not turn the grammar rule (rule.getId()) into any Lucene query because its pattern elements are unsupported for indexing; thrown as UnsupportedPatternRuleException so the caller can skip the rule.

Source

Thrown at languagetool-wikipedia/src/main/java/org/languagetool/dev/index/PatternRuleQueryBuilder.java:81

    this.indexSearcher = indexSearcher;
    this.searchFieldName = searchFieldName;
  }

  /**
   * Iterate over all elements, ignore those not supported, add the other ones to a BooleanQuery.
   * @throws UnsupportedPatternRuleException if no query could be created for the rule
   */
  public Query buildRelaxedQuery(AbstractPatternRule rule) throws UnsupportedPatternRuleException {
    BooleanQuery.Builder builder = new BooleanQuery.Builder();
    for (PatternToken patternToken : rule.getPatternTokens()) {
      try {
        BooleanClause clause = makeQuery(patternToken);
        builder.add(clause);
      } catch (UnsupportedPatternRuleException e) {
        //System.out.println("Ignoring because it's not supported: " + element + ": " + e);
        // cannot handle - okay to ignore, as we may return too broad matches
      } catch (Exception e) {
        throw new RuntimeException("Could not create query for rule " + rule.getId(), e);
      }
    }
    BooleanQuery query = builder.build();
    if (query.clauses().isEmpty()) {
      throw new UnsupportedPatternRuleException("No items found in rule that can be used to build a search query: " + rule);
    }
    return query;
  }

  private BooleanClause makeQuery(PatternToken patternToken) throws UnsupportedPatternRuleException {
    checkUnsupportedElement(patternToken);

    String termStr = patternToken.getString();
    String pos = patternToken.getPOStag();

    BooleanClause termQuery = getTermQueryOrNull(patternToken, termStr);
    BooleanClause posQuery = getPosQueryOrNull(patternToken, pos);

View on GitHub (pinned to 2e990059ce)

Solutions

1. Simplify the rule's pattern tokens to plain terms or POS tags
2. Skip rules that throw this exception when batch-indexing Wikipedia
3. Extend PatternRuleQueryBuilder to support the missing construct

When it happens

Trigger: Thrown at languagetool-wikipedia/src/main/java/org/languagetool/dev/index/PatternRuleQueryBuilder.java:81 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of languagetool-org/languagetool@2e990059ce (2026-09-06). Data as JSON: /api/errors/7f50092108b36a12. Report an issue: GitHub.