languagetool-org/languagetool · error · RuntimeException

IOException while synthesizing suggestions (adj-noun agreeme

Error message

IOException while synthesizing suggestions (adj-noun agreement)

What it means

TokenAgreementAdjNounRule.match() synthesizes inflected adjective suggestions with the Morfologik synthesizer; any IOException from synthesize() is wrapped in a RuntimeException and aborts the rule match. This is a runtime data-lookup failure, not a rule-logic error: the dictionary synthesizer failed while generating inflected forms for suggestions.

Source

Thrown at languagetool-language-modules/uk/src/main/java/org/languagetool/rules/uk/TokenAgreementAdjNounRule.java:334

          }

          for(AnalyzedToken adjToken: state.adjTokenReadings) {
            String newAdjTag = adjToken.getPOSTag().replaceFirst(":.:v_...(:r(in)?anim)?", genderTag + vidmTag);

            String[] synthesized = synthesizer.synthesize(adjToken, newAdjTag, false);

            for (String s : synthesized) {
              String suggestion = s + " " + tokenReadings.getToken();
              if( ! suggestions.contains(suggestion) ) {
                suggestions.add(suggestion);
              }
            }
          }

        }

        } catch (IOException e) {
          throw new RuntimeException(e);
        }

        if( msg.contains("кількісного числівника") ) {
          String suggNum = state.adjAnalyzedTokenReadings.getCleanToken().replaceFirst("[-–]м[аи]$", "")
              + " " + tokenReadings.getToken();
          suggestions.add(suggNum);
        }
        
        if( suggestions.size() > 0 ) {
            potentialRuleMatch.setSuggestedReplacements(suggestions);
        }

        ruleMatches.add(potentialRuleMatch);
      }

      state.reset();
    }

View on GitHub (pinned to 2e990059ce)

Solutions

  1. Inspect e.getCause() to find the underlying I/O failure (resource path, disk, permissions).
  2. Verify the Ukrainian synthesizer dictionary loads correctly (run a minimal synthesize call at startup as a health check).
  3. Rebuild/redistribute the language module jar to ensure dictionary binaries are intact.
  4. Catch the RuntimeException at the rule-engine integration layer and degrade to reporting the disagreement without synthesized suggestions.
  5. Avoid shading/repackaging jars in ways that corrupt binary dictionary entries.

Example fix

// before
} catch (IOException e) {
  throw new RuntimeException(e);
}
// after
} catch (IOException e) {
  LOG.warn("Synthesizer failed for adj-noun suggestions; returning agreement without suggestions", e);
  return toRuleMatchUnsynthesized(msg);
}
Defensive patterns

Strategy: try-catch

Validate before calling

// startup health check
try {
  String[] test = synthesizer.synthesize(new AnalyzedToken("добрий", "adj:m:v_naz", "добрий"), "adj:f:v_naz", true);
  if (test.length == 0) LOG.warn("Ukrainian synthesizer returned no forms");
} catch (IOException e) { throw new IllegalStateException("Synthesizer dictionary broken", e); }

Try / catch

try { matchResult = rule.match(tokens); }
catch (RuntimeException e) {
  if (e.getCause() instanceof IOException) { LOG.error("Suggestion synthesis failed; degrade to no-suggestion match", e); }
  else throw e;
}

Prevention

When it happens

Trigger: A text is analyzed where adj-noun disagreement is detected and the rule calls synthesizer.synthesize(...) for suggestions, but the underlying dictionary stream/lookup throws IOException (broken dictionary resource, corrupt cache, I/O failure).

Common situations: Corrupted or partially extracted Morfologik dictionary in the deployed artifact; filesystem/disk errors when the dictionary is memory-mapped from disk; running LanguageTool on a read-only or failing volume.

Understand the failure class

Background: "failed to read file", EACCES, ENOENT and "could not read <path>" errors: when a program can't read a file from disk — this error's family across 49 libraries.

Related errors

AI-assisted analysis of languagetool-org/languagetool@2e990059ce (2026-09-06). Data as JSON: /api/errors/04ea02b3c6caf666. Report an issue: GitHub.