pentaho/pentaho-kettle · error · KettleException

UserDefinedJavaClassMeta.Exception.UnexpectedErrorInReadingS…

Error message

UserDefinedJavaClassMeta.Exception.UnexpectedErrorInReadingStepInfo

What it means

Generic wrap thrown from UserDefinedJavaClassMeta.readRep() when reading the UDJC step's settings from a repository fails unexpectedly. It uses the localized message key UnexpectedErrorInReadingStepInfo and preserves the cause. This happens while loading a transformation definition from a Kettle repository.

Solutions

Inspect the wrapped cause to see whether it is connectivity or data-related.
Test repository connection and re-open the transformation.
Export the transformation to XML and inspect/repair the UDJC step's snippet and field-info attributes.
If version mismatch, open the transformation in the version it was created with and re-save.
Recreate the UDJC step and paste the code back if stored attributes are corrupt.

Defensive patterns

Strategy: try-catch

Validate before calling

// Before loading, verify repository reachable
if (!repository.isConnected()) { repository.connect(); }

Try / catch

try {
  TransMeta tm = new TransMeta(repository, directory, name, metaStore);
} catch (KettleException e) {
  if (e.getMessage().contains("UnexpectedErrorInReadingStepInfo")) {
    // fall back to loading from XML export
  }
}

Prevention

Keep repository connections healthy; reconnect on failure
Export critical transformations to XML as backup
Avoid opening transformations written by much older Pentaho versions directly
Re-save transformations after version upgrades

When it happens

Trigger: Calling readRep during transformation load; underlying rep.getStepAttributeString/Int calls throw (repository connection failure, schema mismatch, corrupt stored attributes, incompatible serialization).

Common situations: Loading an old transformation whose stored step attributes conflict with the current version; DB repository connectivity issues mid-read; corrupted repository rows; manually edited repository data.

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 pentaho/pentaho-kettle@f3058517a1 (2026-09-13). Data as JSON: /api/errors/9dfeff696b7a8021. Report an issue: GitHub.

Appendix: source

Thrown at engine/src/main/java/org/pentaho/di/trans/steps/userdefinedjavaclass/UserDefinedJavaClassMeta.java:625

        stepDefinition.stepName =
          rep.getStepAttributeString( id_step, i, ElementNames.target_.name() + ElementNames.step_name.name() );
        stepDefinition.description =
          rep.getStepAttributeString( id_step, i, ElementNames.target_.name()
            + ElementNames.step_description.name() );
        targetStepDefinitions.add( stepDefinition );
      }

      int nrParameters = rep.countNrStepAttributes( id_step, ElementNames.parameter_tag.name() );
      for ( int i = 0; i < nrParameters; i++ ) {
        UsageParameter usageParameter = new UsageParameter();
        usageParameter.tag = rep.getStepAttributeString( id_step, i, ElementNames.parameter_tag.name() );
        usageParameter.value = rep.getStepAttributeString( id_step, i, ElementNames.parameter_value.name() );
        usageParameter.description =
          rep.getStepAttributeString( id_step, i, ElementNames.parameter_description.name() );
        usageParameters.add( usageParameter );
      }
    } catch ( Exception e ) {
      throw new KettleException( BaseMessages.getString(
        PKG, "UserDefinedJavaClassMeta.Exception.UnexpectedErrorInReadingStepInfo" ), e );
    }
  }

  public void saveRep( Repository rep, IMetaStore metaStore, ObjectId id_transformation, ObjectId id_step ) throws KettleException {
    try {

      for ( int i = 0; i < definitions.size(); i++ ) {
        UserDefinedJavaClassDef def = definitions.get( i );
        rep.saveStepAttribute( id_transformation, id_step, i, ElementNames.class_name.name(), def.getClassName() );
        rep.saveStepAttribute( id_transformation, id_step, i, ElementNames.class_source.name(), def.getSource() );
        rep.saveStepAttribute( id_transformation, id_step, i, ElementNames.class_type.name(), def
          .getClassType().name() );
      }

      for ( int i = 0; i < fields.size(); i++ ) {
        FieldInfo fi = fields.get( i );
        rep.saveStepAttribute( id_transformation, id_step, i, ElementNames.field_name.name(), fi.name );

View on GitHub (pinned to f3058517a1)