看起来jhlrc没有api可供获取 _cat/nodes api，但是可以使用jhlrc中提供的低级客户机轻松获得它，如下面的代码所示

private void getNodesAPI(RestHighLevelClient restHighLevelClient) throws IOException {
        RestClient lowLevelClient = restHighLevelClient.getLowLevelClient();
        Request request = new Request(
                "GET",
                "/_cat/nodes?v");
        Response response = lowLevelClient.performRequest(request);
        if (response.getStatusLine().getStatusCode() == 200) {
            System.out.println("resp: \n"+ EntityUtils.toString(response.getEntity()));
        }
    }

上面的代码在本地运行并且可以工作，下面是控制台上的o/p

ip        heap.percent ram.percent cpu load_1m load_5m load_15m node.role master name
127.0.0.1           48          99  21    2.59    1.93     1.92 *    opster