class RevocationHelper extends AbstractHelper {

  public static synchronized RevocationHelper getInstance() {
    log.info("RevocationHelper.getInstance : " + instance
        + (instance == null ? "" : " : " + instance));
    if (instance == null) {
      throw new IllegalStateException("getInstance not called before using IssuanceHelper!");
    }
    return instance;
  }

  private  RevocationHelper(String revocationStoragePrefix, String revocationResourcesPrefix);

}