pentaho/pentaho-kettle · error · MissingResourceException

Format problem with key=

Error message

Format problem with key=[${key}], locale=[${locale}], package=${packageName} : ${e}

What it means

calculateString formats a message-bundle entry with MessageFormat; if the pattern is malformed or arguments don't match placeholders, MessageFormat throws IllegalArgumentException, which is converted into a MissingResourceException carrying 'Format problem with key=[key], locale=[locale], package=packageName'. The bundle exists but its template cannot be formatted with the supplied arguments.

Solutions

  1. Inspect the properties file entry for the key in the reported locale/package; fix the MessageFormat pattern (escape quotes as '', verify {0},{1} indices).
  2. Match the argument count/types to the placeholders in the message template.
  3. Test the key with the default English bundle to isolate locale-specific breakage.
  4. Catch MissingResourceException around getString calls for user-supplied/custom bundles.

Example fix

// broken properties entry
MyApp.Error=Can't open file {0} for {1,number}
// fixed
MyApp.Error=Can''t open file {0} for record {1}
// and call: BaseMessages.getString(PKG, "MyApp.Error", fileName, recordId);
Defensive patterns

Strategy: try-catch

Validate before calling

try {
  new java.text.MessageFormat(bundle.getString(key), locale).format(args);
} catch (IllegalArgumentException e) { /* bad pattern or args */ }

Try / catch

try {
  msg = BaseMessages.getString(PKG, key, args);
} catch (MissingResourceException e) {
  log.error("Bad message pattern for " + key + ": " + e.getMessage());
  msg = key; // safe fallback
}

Prevention

When it happens

Trigger: BaseMessages.getString(PKG, key, args...) where the properties entry has a malformed {0} pattern (unclosed brace, bad format type) or the argument types mismatch (e.g. passing a String where {0,number} expects a Number) for the resolved locale.

Common situations: Custom-translated properties files with broken MessageFormat syntax, passing wrong number/type of substitution arguments, locale-specific pattern differences, single quotes in messages not escaped ('' needed) breaking placeholders.

Understand the failure class

Background: "Invalid ... format", "must be in format X", "does not look like a ..." — invalid argument format errors across CLI tools and libraries — this error's family across 17 libraries.

Related errors

AI-assisted analysis of pentaho/pentaho-kettle@f3058517a1 (2026-09-13). Data as JSON: /api/errors/5e43f3ecee775219. Report an issue: GitHub.

Appendix: source

Thrown at core/src/main/java/org/pentaho/di/i18n/GlobalMessageUtil.java:273

    return calculateString( packageName, locale, key, parameters, resourceClass, bundleName, true );
  }

  @VisibleForTesting
  static String calculateString( final String packageName, final Locale locale, final String key,
                                 final Object[] parameters, final Class<?> resourceClass, final String bundleName,
                                 final boolean fallbackOnRoot ) throws MissingResourceException {
    try {
      ResourceBundle bundle = getBundle( locale, packageName + "." + bundleName, resourceClass, fallbackOnRoot );
      String unformattedString = bundle.getString( key );
      String string = MessageFormat.format( unformattedString, parameters );
      return string;
    } catch ( IllegalArgumentException e ) {
      final StringBuilder msg = new StringBuilder();
      msg.append( "Format problem with key=[" ).append( key ).append( "], locale=[" ).append( locale ).append(
        "], package=" ).append( packageName ).append( " : " ).append( e.toString() );
      log.error( msg.toString() );
      log.error( Const.getStackTracker( e ) );
      throw new MissingResourceException( msg.toString(), packageName, key );
    }
  }

  /**
   * Retrieve a resource bundle of the default or fail-over locales.
   *
   * @param packagePath   The package to search in
   * @param resourceClass the class to use to resolve the bundle
   * @return The resource bundle
   * @throws MissingResourceException in case both resource bundles couldn't be found.
   */
  public static ResourceBundle getBundle( final String packagePath, final Class<?> resourceClass )
    throws MissingResourceException {
    final Set<Locale> activeLocales = getActiveLocales();
    for ( final Locale locale : activeLocales ) {
      try {
        return getBundle( locale, packagePath, resourceClass );
      } catch ( MissingResourceException e ) {

View on GitHub (pinned to f3058517a1)