zxing/zxing · error · IllegalArgumentException

Invalid parent dir:

Error message

Invalid parent dir: 

What it means

Thrown by StringsResourceTranslator.translate when the parent directory name of the translated (target) strings.xml file does not match the regex values-(.+). The tool is built specifically for the Android resource layout where localized files live under res/values-<locale>/strings.xml; any other directory naming is rejected. The matched group becomes the language code passed to the Google Translate API.

Source

Thrown at javase/src/main/java/com/google/zxing/client/j2se/StringsResourceTranslator.java:120

        VALUES_DIR_PATTERN.matcher(entry.getFileName().toString()).matches();
    try (DirectoryStream<Path> dirs = Files.newDirectoryStream(resDir, filter)) {
      for (Path dir : dirs) {
        translate(stringsFile, dir.resolve("strings.xml"), forceRetranslation);
      }
    }
  }

  private static void translate(Path englishFile,
                                Path translatedFile,
                                Collection<String> forceRetranslation) throws IOException {

    Map<String, String> english = readLines(englishFile);
    Map<String,String> translated = readLines(translatedFile);
    String parentName = translatedFile.getParent().getFileName().toString();

    Matcher stringsFileNameMatcher = STRINGS_FILE_NAME_PATTERN.matcher(parentName);
    if (!stringsFileNameMatcher.find()) {
      throw new IllegalArgumentException("Invalid parent dir: " + parentName);
    }
    String language = stringsFileNameMatcher.group(1);
    String massagedLanguage = LANGUAGE_CODE_MASSAGINGS.get(language);
    if (massagedLanguage != null) {
      language = massagedLanguage;
    }

    System.out.println("Translating " + language);

    Path resultTempFile = Files.createTempFile(null, null);

    boolean anyChange = false;
    try (Writer out = Files.newBufferedWriter(resultTempFile, StandardCharsets.UTF_8)) {
      out.write("<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n");
      out.write(APACHE_2_LICENSE);
      out.write("<resources>\n");

      for (Map.Entry<String,String> englishEntry : english.entrySet()) {

View on GitHub (pinned to 19aa2d8254)

Solutions

1. Ensure the target file path follows res/values-<locale>/strings.xml (e.g. res/values-fr/strings.xml) so the parent dir matches values-(.+).
2. Create the proper localized values directory before running the tool and pass that path as translatedFile.
3. Verify with the STRINGS_FILE_NAME_PATTERN: the parent folder name must start with 'values-'.

Example fix

// before
translate(Paths.get("res/values/strings.xml"),
         Paths.get("res/fr/strings.xml"), force);

// after
translate(Paths.get("res/values/strings.xml"),
         Paths.get("res/values-fr/strings.xml"), force);

Path parent = translatedFile.getParent();
String parentName = parent != null && parent.getFileName() != null
    ? parent.getFileName().toString() : "";
if (!parentName.matches("values-(.+)")) {
  throw new IllegalArgumentException(
    "Target dir must be values-<locale>, was: " + parentName);
}

boolean isValuesLocaleDir(Path p) {
  if (p == null || p.getFileName() == null) return false;
  return p.getFileName().toString().matches("values-(.+)");
}

try {
  translator.translate(englishFile, translatedFile, force);
} catch (IllegalArgumentException e) {
  // parent dir was not values-<locale>; point user at the right Android folder
}

When it happens

Trigger: Calling translate(englishFile, translatedFile, forceRetranslation) where translatedFile.getParent().getFileName() is not of the form values-XX (e.g. the file sits directly under 'res/values/', or under 'res/values/', or a custom folder like 'res/strings-fr/').

Common situations: Pointing the translator at the default English res/values/ instead of a localized res/values-fr/ directory; restructuring Android resources so localized files no longer follow the values-<lang> convention; passing a temp/absolute path whose parent is not an Android values directory.

Related errors

• Addresses and types lengths differ
• Both dimensions must be greater than 0
• row lengths do not match
• illegal character encountered: {stringRepresentation.substri
• input matrix dimensions do not match

AI-assisted analysis of zxing/zxing@19aa2d8254 (2026-08-14). Data as JSON: /api/errors/3b98292c5c7bb2c0. Report an issue: GitHub.