/**
  * 广播消息
  *
  * @param message
  */
 private void broadcast(String message, IoSession exceptSession) { // (8)
   synchronized (sessions) {
     for (IoSession session : sessions) {
       if (session.isConnected()) {
         if (session.equals(exceptSession)) {
           session.write("[You]" + message);
         } else {
           session.write("[Client" + session.getRemoteAddress() + "] " + message);
         }
       }
     }
   }
 }