private static Properties loadProperties(File antJar) throws ConfigurationException {
    Properties properties = JarUtil.loadProperties(antJar, VERSION_RESOURCE);
    if (properties == null) {
      throw new ConfigurationException(AntBundle.message("cant.read.from.ant.jar.error.message", antJar.getAbsolutePath()));
    }
    return properties;
  }
private static Properties loadProperties(File antJar)