code: private boolean isConfigChanged(boolean init)
        throws IOException {
      if (init &&
          (configFileName == null ||
              (poolsConfigFileName == null &&
                  conf.onlyAllowConfiguredPools()))) {
        throw new IOException("ClusterManager needs a config and a " +
            "pools file to start");
      }
      if (configFileName == null && poolsConfigFileName == null) {
        return false;
      }
  
      boolean configChanged = false;
  
      if (configFileName != null) {
        File file = new File(configFileName);
        configChanged |= (file.lastModified() == 0 ||
          file.lastModified() > lastSuccessfulReload);
      }
  
  
      if (poolsConfigFileName != null) {
        File file = new File(poolsConfigFileName);
        configChanged |= (file.lastModified() == 0 ||
            file.lastModified() > lastSuccessfulReload);
      }
  
      return configChanged;
    }
docs: Check if the config files have changed since they were last read
  @return true if the modification time of the file is greater
  than that of the last successful reload, false otherwise
  @param init true when the config manager is being initialized.
  false on reloads