//                                                                           =========
    private static final BadWordDbm _instance = new BadWordDbm();

    private BadWordDbm() {
    }

    public static BadWordDbm getInstance() {
        return _instance;
    }

    // ===================================================================================

    //                                                                           =========
    private static final FailureUrlDbm _instance = new FailureUrlDbm();

    private FailureUrlDbm() {
    }

    public static FailureUrlDbm getInstance() {
        return _instance;
    }

    // ===================================================================================

    //                                                                           =========
    private static final CrawlingInfoParamDbm _instance = new CrawlingInfoParamDbm();

    private CrawlingInfoParamDbm() {
    }

    public static CrawlingInfoParamDbm getInstance() {
        return _instance;
    }

    // ===================================================================================

    //                                                                           =========
    private static final WebAuthenticationDbm _instance = new WebAuthenticationDbm();

    private WebAuthenticationDbm() {
    }

    public static WebAuthenticationDbm getInstance() {
        return _instance;
    }

    // ===================================================================================

    //                                                                           =========
    private static final DataConfigDbm _instance = new DataConfigDbm();

    private DataConfigDbm() {
    }

    public static DataConfigDbm getInstance() {
        return _instance;
    }

    // ===================================================================================

    //                                                                           =========
    private static final RelatedContentDbm _instance = new RelatedContentDbm();

    private RelatedContentDbm() {
    }

    public static RelatedContentDbm getInstance() {
        return _instance;
    }

    // ===================================================================================

    //                                                                           =========
    private static final ScheduledJobDbm _instance = new ScheduledJobDbm();

    private ScheduledJobDbm() {
    }

    public static ScheduledJobDbm getInstance() {
        return _instance;
    }

    // ===================================================================================

   */
  @GwtIncompatible // Class.cast, Class.isInstance
  public static <X extends Throwable> void throwIfInstanceOf(
      Throwable throwable, Class<X> declaredType) throws X {
    checkNotNull(throwable);
    if (declaredType.isInstance(throwable)) {
      throw declaredType.cast(throwable);
    }
  }

  /**
   * Propagates {@code throwable} exactly as-is, if and only if it is an instance of {@code
   * declaredType}. Example usage:

    //                                                                           =========
    private static final KeyMatchDbm _instance = new KeyMatchDbm();

    private KeyMatchDbm() {
    }

    public static KeyMatchDbm getInstance() {
        return _instance;
    }

    // ===================================================================================

    //                                                                           =========
    private static final FileAuthenticationDbm _instance = new FileAuthenticationDbm();

    private FileAuthenticationDbm() {
    }

    public static FileAuthenticationDbm getInstance() {
        return _instance;
    }

    // ===================================================================================