Settings settings = Settings.builder().put("cluster.name", "xxx")

                    .put("xpack.security.transport.ssl.enabled", false)

                    .put("xpack.security.user", "xxx:xxx")

                    .put("client.transport.sniff", true).build();

try {

    client = new PreBuiltXPackTransportClient(settings)

            .addTransportAddress(new InetSocketTransportAddress(InetAddress.getByName("xxx.xxx.xxx.xxx"), 9300))

            .addTransportAddress(new InetSocketTransportAddress(InetAddress.getByName("xxx.xxx.xxx.xxx"), 9300));

} catch (UnknownHostException e) {

    e.printStackTrace();

}