code: public static void putValue(String key, Object newValue) {
          Object oldValue = CFG.get(key);
          if (changed(oldValue, newValue)) {
              CFG.put(key, newValue);
              List<RpcConfigListener> rpcConfigListeners = CFG_LISTENER.get(key);
              if (CommonUtils.isNotEmpty(rpcConfigListeners)) {
                  for (RpcConfigListener rpcConfigListener : rpcConfigListeners) {
                      rpcConfigListener.onChange(oldValue, newValue);
                  }
              }
          }
      }
docs: Put value.
  
  @param key      the key
  @param newValue the new value