如何在jest elasticsearch中使用maxAggregation

JestClientFactory factory = new JestClientFactory();
factory.setHttpClientConfig(new HttpClientConfig.Builder("http://localhost:9200").build());
JestClient client = factory.getObject();

SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();
searchSourceBuilder.aggregation(AggregationBuilders.max("max_value").field("field_name"));

Search search = new Search.Builder(searchSourceBuilder.toString())
        .addIndex("index_name")
        .addType("type_name")
        .build();

SearchResult result = client.execute(search);
MaxAggregation maxAggregation = result.getAggregations().getMaxAggregation("max_value");
Double maxValue = maxAggregation.getMax();