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

  public void setSocketAddr(String name, InetSocketAddress addr) {
    set(name, NetUtils.getHostPortString(addr));
  }

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

}