docs: public static ClientSelector ipSelector(final String ipMask) {
          return new ClientSelector() {
              @Override
              public boolean select(Client client) {
                  return AddressUtil.matchInterface(client.getSocketAddress().getAddress().getHostAddress(), ipMask);
              }
  
              @Override
              public String toString() {
                  return "ClientSelector{ipMask:" + ipMask + " }";
              }
          };
      }