MissingResourceException: не удается найти пакет для базового имени resources.controls.controls_res, языковой стандарт en

Не могу понять в чем проблема, почему он ругается и не может найти locale en. Есть ли проблема с путями или boundle именами?

Проект legacy, написанный 15 лет назад, раньше был в Ant, сейчас его перевели на Gradle, появилась эта ошибка. Он строится на Ant без проблем.

P.S. Я отметил строки, на которые ссылаются ошибки, отдельно в классах.

ОШИБКИ:

java.lang.ExceptionInInitializerError
    at org.opensourcephysics.controls.OSPLog.<init>(OSPLog.java:937)
    at org.opensourcephysics.controls.OSPLog.getOSPLog(OSPLog.java:124)
    at org.opensourcephysics.cabrillo.tracker.Tracker.loadPreferences(Tracker.java:1391)
    at org.opensourcephysics.cabrillo.tracker.Tracker.<clinit>(Tracker.java:251)
Caused by: java.util.MissingResourceException: Can't find bundle for base name org.opensourcephysics.resources.controls.controls_res, locale en
Caused by: java.util.MissingResourceException: Can't find bundle for base name org.opensourcephysics.resources.controls.controls_res, locale en

    at java.util.ResourceBundle.throwMissingResourceException(ResourceBundle.java:1581)
    at java.util.ResourceBundle.getBundleImpl(ResourceBundle.java:1396)
    at java.util.ResourceBundle.getBundle(ResourceBundle.java:854)
    at org.opensourcephysics.controls.ControlsRes.<clinit>(ControlsRes.java:55)
    ... 4 more
Caused by: java.lang.NullPointerException
    at java.util.Properties$LineReader.readLine(Properties.java:434)
    at java.util.Properties.load0(Properties.java:353)
    at java.util.Properties.load(Properties.java:341)
    at java.util.PropertyResourceBundle.<init>(PropertyResourceBundle.java:138)
    at org.opensourcephysics.resources.controls.controls_res.<init>(controls_res.java:32)
    at org.opensourcephysics.resources.controls.controls_res.<init>(controls_res.java:23)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
    at java.lang.Class.newInstance(Class.java:442)
    at java.util.ResourceBundle$Control.newBundle(ResourceBundle.java:2662)
Caused by: java.lang.NullPointerException

    at java.util.ResourceBundle.loadBundle(ResourceBundle.java:1518)
    at java.util.ResourceBundle.findBundle(ResourceBundle.java:1482)
    at java.util.ResourceBundle.findBundle(ResourceBundle.java:1436)
    at java.util.ResourceBundle.getBundleImpl(ResourceBundle.java:1370)
    ... 6 more
Exception in thread "main" 
Execution failed for task ':Tracker.main()'.

Как видно из логов, все ошибки вызваны тем, что не может найти *locale en*.

Класс control_res:

public class controls_res extends PropertyResourceBundle {
  // relative path to strings
  static String res = "controls_res.properties"; //$NON-NLS-1$

  /**
   * Constructor tools
   * @throws IOException
   */
  public controls_res() throws IOException {
    this(controls_res.class.getResourceAsStream(res)); 23 STRING!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
  }

  /**
   * Constructor tools
   * @param stream
   * @throws IOException
   */
  public controls_res(InputStream stream) throws IOException {
    super(stream);  // 32 STRING!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
  }
}

Классcontrols_res_en:

/**
 * English resource loader for OSP controls class.  Resource strings are obtained from superclass.
 * @author Wolfgang Christian
*/
public class controls_res_en extends controls_res {
  /**
   * Constructor controls_res_en
   * @throws IOException
   */
  public controls_res_en() throws IOException {
    super();
  }
}

Класс ControlsRes:

public class ControlsRes {
  // static constants for speed
  public static String ANIMATION_NEW;
  public static String ANIMATION_INIT;
  public static String ANIMATION_STEP;
  public static String ANIMATION_RESET;
  public static String ANIMATION_START;
  public static String ANIMATION_STOP;
  public static String ANIMATION_RESET_TIP;
  public static String ANIMATION_INIT_TIP;
  public static String ANIMATION_START_TIP;
  public static String ANIMATION_STOP_TIP;
  public static String ANIMATION_NEW_TIP;
  public static String ANIMATION_STEP_TIP;
  public static String CALCULATION_CALC;
  public static String CALCULATION_RESET;
  public static String CALCULATION_CALC_TIP;
  public static String CALCULATION_RESET_TIP;
  public static String XML_NAME;
  public static String XML_VALUE;
  static final String BUNDLE_NAME = "org.opensourcephysics.resources.controls.controls_res"; //$NON-NLS-1$
  static ResourceBundle res;

  // private constructor because all methods are static
  private ControlsRes() {}

  static {
    String language = Locale.getDefault().getLanguage();
    Locale resourceLocale = Locale.ENGLISH;
    for(Locale locale : OSPRuntime.getInstalledLocales()) {
      if (locale.getLanguage().equals(language)) {
        resourceLocale = locale;
        break;
      }
    }
    res = ResourceBundle.getBundle(BUNDLE_NAME, resourceLocale); // 55 String!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
    setLocalStrings();
  }

  private static String getString(final ResourceBundle bundle, final String key) {
    try {
      return bundle.getString(key);
    } catch(final MissingResourceException ex) {
      return '|'+key+'|';
    }
  }

  public static void setLocale(Locale locale) {
    res = ResourceBundle.getBundle(BUNDLE_NAME, locale);
    setLocalStrings();
  }

  /**
   * Gets the localized value of a string. If no localized value is found, the
   * key is returned surrounded by exclamation points.
   *
   * @param key the string to localize
   * @return the localized string
   */
  static public String getString(String key) {
    try {
      return res.getString(key);
    } catch(MissingResourceException ex) {
      return "!"+key+"!"; //$NON-NLS-1$ //$NON-NLS-2$
    }
  }

  /**
  * Gets the local strings.  Static strings are used for speed to avoid having to call the resource object.
  */
  private static void setLocalStrings() {
    ANIMATION_NEW = getString(res, "ANIMATION_NEW");                 //$NON-NLS-1$
    ANIMATION_INIT = getString(res, "ANIMATION_INIT");               //$NON-NLS-1$
    ANIMATION_STEP = getString(res, "ANIMATION_STEP");               //$NON-NLS-1$
    ANIMATION_RESET = getString(res, "ANIMATION_RESET");             //$NON-NLS-1$
    ANIMATION_START = getString(res, "ANIMATION_START");             //$NON-NLS-1$
    ANIMATION_STOP = getString(res, "ANIMATION_STOP");               //$NON-NLS-1$
    ANIMATION_RESET_TIP = getString(res, "ANIMATION_RESET_TIP");     //$NON-NLS-1$
    ANIMATION_INIT_TIP = getString(res, "ANIMATION_INIT_TIP");       //$NON-NLS-1$
    ANIMATION_START_TIP = getString(res, "ANIMATION_START_TIP");     //$NON-NLS-1$
    ANIMATION_STOP_TIP = getString(res, "ANIMATION_STOP_TIP");       //$NON-NLS-1$
    ANIMATION_NEW_TIP = getString(res, "ANIMATION_NEW_TIP");         //$NON-NLS-1$
    ANIMATION_STEP_TIP = getString(res, "ANIMATION_STEP_TIP");       //$NON-NLS-1$
    CALCULATION_CALC = getString(res, "CALCULATION_CALC");           //$NON-NLS-1$
    CALCULATION_RESET = getString(res, "CALCULATION_RESET");         //$NON-NLS-1$
    CALCULATION_CALC_TIP = getString(res, "CALCULATION_CALC_TIP");   //$NON-NLS-1$
    CALCULATION_RESET_TIP = getString(res, "CALCULATION_RESET_TIP"); //$NON-NLS-1$
    XML_NAME = getString(res, "XML_NAME");                           //$NON-NLS-1$
    XML_VALUE = getString(res, "XML_VALUE");                         //$NON-NLS-1$
  }
}