RestClient-多条件聚合

在对应的service层里面写：

 HotelService里的代码如下：

@Override
    public Map<String, List<String>> filters()  {

        try {
            //1. 准备Request
            SearchRequest request = new SearchRequest("hotel");
            //2. 准备DSL
            //2.1 设置size
            request.source().size(0);
            //2.2 聚合
            buildAggretgaion(request);

            //3. 发出请求
            SearchResponse response = client.search(request,RequestOptions.DEFAULT);

            //4. 解析结果
            Map<String,List<String>> result = new HashMap<String, List<String>>();
            Aggregations aggregations = response.getAggregations();
            //4.1 根据品牌（聚合名称）名称获取品牌的结果
            List<String> brandList = getAddByName(aggregations,"brandAgg");
            result.put("品牌",brandList); //放入map
            //4.2 根据城市（聚合名称）名称获取品牌的结果
            List<String> cityList = getAddByName(aggregations,"cityList");
            result.put("城市",cityList); //放入map
            //4.3 根据星级（聚合名称）名称获取品牌的结果
            List<String> starList = getAddByName(aggregations,"starList");
            result.put("星级",starList); //放入map

            return result;

        } catch (IOException e) {
            throw new RuntimeException();
        }
    }

    //(抽取出来的) 根据名称获取品牌的结果
    private List<String> getAddByName(Aggregations aggregations, String aggName) {
        //4.1 根据聚合名称获取聚合结果
        Terms brandTerms = aggregations.get(aggName);
        //4.2 获取buckets
        List<? extends Terms.Bucket> buckets = brandTerms.getBuckets();
        //4.3 遍历
        List<String> brandList = new ArrayList<String>();
        for(Terms.Bucket bucket : buckets){
            //4.4 获取key
            String key = bucket.getKeyAsString();
            brandList.add(key);

            System.out.println(key);
        }
        return brandList;
    }

    //抽取出来的 聚合
    private void buildAggretgaion(SearchRequest request) {
        request.source().aggregation(AggregationBuilders
                .terms("brandAgg")
                .field("brand")
                .size(10)
        );
        request.source().aggregation(AggregationBuilders
                .terms("cityAgg")
                .field("city")
                .size(10)
        );
        request.source().aggregation(AggregationBuilders
                .terms("starAgg")
                .field("starName.keyword")
                .size(10)
        );
    }