i've customized transportclient of elasticsearch and I want to migrate to RestClient
restHighLevelClient.indexAsync(indexRequest, new ActionListener<IndexResponse>() {
                @Override
                public void onResponse(IndexResponse indexResponse) {
                    // called when the operation is successfully completed
                }
                @Override
                public void onFailure(Exception e) {
                    // called on failure
                }
            });
