class Configuration implements Iterable<Map.Entry<String,String>>,
                                      Writable {

  @Override
  public String toString() {
    StringBuilder sb = new StringBuilder();
    sb.append("Configuration: ");
    if(loadDefaults) {
      toString(defaultResources, sb);
      if(resources.size()>0) {
        sb.append(", ");
      }
    }
    toString(resources, sb);
    return sb.toString();
  }

  public  Configuration();
  public  Configuration(boolean loadDefaults);
  @SuppressWarnings("unchecked") public  Configuration(Configuration other);

}