ES进阶 -- Java客户端

 //快速入门
    @Test
    void  testmatchall() throws IOException {
       //1.准备request
        SearchRequest request = new SearchRequest("hotel");
        //2. 准备dsl
         request.source().query(QueryBuilders.matchAllQuery());
        //3.发送请求
        SearchResponse response =   client.search(request,RequestOptions.DEFAULT);
        //4.解析响应
        SearchHits searchHits = response.getHits();
        //4.1 获取总条数
        long total = searchHits.getTotalHits().value;
        System.out.println("共搜索到："+ total);
        //4.2文档数组
        SearchHit[] hits = searchHits.getHits();
        //4.3遍历
        for (SearchHit hit : hits){
            //得到json
            String json = hit.getSourceAsString();
            //转换对象
            HotelDoc hotelDoc = JSON.parseObject(json, HotelDoc.class);
            System.out.println("hotelDoc = " + hotelDoc);
        }
        System.out.println(response);

    }

private PageResult handleResponse(SearchResponse response) {
        //4.解析响应
        SearchHits searchHits = response.getHits();
        //4.1获取总条数
        long total = searchHits.getTotalHits().value;
        //4.2文档数组
        SearchHit[] hits = searchHits.getHits();
        //4.3遍历
        List<HotelDoc> hotels = new ArrayList<>();
        for (SearchHit hit : hits){
            //获取文档source
            String json = hit.getSourceAsString();
            //反序列化
            HotelDoc hotelDoc = JSON.parseObject(json, HotelDoc.class);
            //获取排序值
            Object[] sortValues = hit.getSortValues();
            if (sortValues.length > 0 ){
                Object sortValue = sortValues[0];
                hotelDoc.setDistance(sortValue);
            }

            hotels.add(hotelDoc);
        }
        //4.4封装返回
        return new PageResult(total,hotels);
    }

    //2.算分控制
        FunctionScoreQueryBuilder functionScoreQuery =
                   QueryBuilders.functionScoreQuery(
                           //原始查询，做相关性算分
                           boolQueryBuilder,
                           //function score数组
                           new FunctionScoreQueryBuilder.FilterFunctionBuilder[]{
                                   //其中一个function score元素
                                new FunctionScoreQueryBuilder.FilterFunctionBuilder(
                                        //过滤条件
                                        QueryBuilders.termQuery("isAD",true),
                                        //算分函数
                                        ScoreFunctionBuilders.weightFactorFunction(10)
                                )
                });

@Service
public class HotelService  implements IHotelService {

    @Autowired
    public HotelMapper hotelMapper;
    @Autowired
    private RestHighLevelClient client;


    @Override
    public List<Hotel> listhotel() {
      System.out.println(hotelMapper.listhotel());
        return hotelMapper.listhotel();
    }

    @Override
    public Hotel getById(long id) {

        return hotelMapper.getById(id);
    }

    @Override
    public PageResult search(RequestParams params) {
        try {
            //1.准备request
            SearchRequest request = new SearchRequest("hotel");
            //2.准备dsl
            //2.1 query查询
            buildBaisc(params, request);

            //2.2 分页
            int page = params.getPage();
            int size = params.getSize();
            request.source().from((page - 1) * size).size(size);

            //2.3排序
            String location = params.getLocation();
             if (location != null && !location.equals("")){
                request.source().sort(SortBuilders
                        .geoDistanceSort("location",new GeoPoint(location))
                        .order(SortOrder.ASC)
                        .unit(DistanceUnit.KILOMETERS)
                );
             }

            //3.发送请求
            SearchResponse response = client.search(request, RequestOptions.DEFAULT);
            //4.解析响应
            return handleResponse(response);

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


    public Map<String, List<String>> filters(RequestParams params){
        
        try {
        //1.准备reuest
        SearchRequest request = new SearchRequest("hotel");
        //2.准备dsl
        //2.1准备query
        buildBaisc(params, request);
        //2.1 设置size
        request.source().size(0);
        //2.2聚合
        buildAggregation(request);
        /* 3.发出 */
        SearchResponse response = client.search(request, RequestOptions.DEFAULT);
            System.out.println("response = " + response);
        //4.解析结果
        Map<String,List<String>> result = new HashMap<>();
        Aggregations aggregations = response.getAggregations();
        //4.1根据品牌获取品牌结果
        List<String> brandList =  getAggByname(aggregations,"brandAgg");
        result.put("品牌",brandList);
        //4.2根据品牌获取品牌结果
        List<String> cityList =  getAggByname(aggregations,"cityAgg");
        result.put("城市",cityList);
        //4.3根据品牌获取品牌结果
        List<String> starList =  getAggByname(aggregations,"starNameAgg");
        result.put("星级",starList);
       
        return result;
        
        } catch (IOException e) {
             throw  new RuntimeException();
        }
    }

    private List<String> getAggByname(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<>();
        for (Terms.Bucket bucket:buckets){
            //4.4获取key
            String key = bucket.getKeyAsString();
             brandList.add(key);
        }
        return brandList;
    }

    private void buildAggregation(SearchRequest request) {
        request.source().aggregation(AggregationBuilders
                .terms("brandAgg")
                .field("brand")
                .size(100)
        );
        request.source().aggregation(AggregationBuilders
                .terms("cityAgg")
                .field("city")
                .size(100)
        );
        request.source().aggregation(AggregationBuilders
                .terms("starNameAgg")
                .field("starName")
                .size(100)
        );
    }

    private void buildBaisc(RequestParams params, SearchRequest request) {

        // 1.构建BooleanQuery
        BoolQueryBuilder boolQuery = QueryBuilders.boolQuery();

        String key = params.getKey();
        if (key == null ||  "".equals(key)) {
            boolQuery.must(QueryBuilders.matchAllQuery());
        } else {
            boolQuery.must(QueryBuilders.matchQuery("all", key));
        }
        // 城市条件
        if (params.getCity() != null && !params.getCity().equals("")){
            boolQuery.filter(QueryBuilders.termQuery("city", params.getCity()));
        }
        //品牌条件
        if (params.getBrand() !=null && !params.getBrand().equals("")){
            boolQuery.filter(QueryBuilders.termQuery("brand", params.getBrand()));
        }
        //星级条件
        if (params.getStarName() !=null && !params.getStarName().equals("")){
            System.out.println(params.getStarName());
            boolQuery.filter(QueryBuilders.termQuery("starName", params.getStarName()));
        }
        //价格条件
        if ( params.getMinPrice()!=null && params.getMaxPrice()!=null){
            boolQuery.filter(QueryBuilders.rangeQuery("price").gte(params.getMinPrice()).lte(params.getMaxPrice()));
        }

        //2.算分控制
        FunctionScoreQueryBuilder functionScoreQuery =
                   QueryBuilders.functionScoreQuery(
                           //原始查询，做相关性算分
                           boolQuery,
                           //function score数组
                           new FunctionScoreQueryBuilder.FilterFunctionBuilder[]{
                                   //其中一个function score元素
                                new FunctionScoreQueryBuilder.FilterFunctionBuilder(
                                        //过滤条件
                                        QueryBuilders.termQuery("aD",true),
                                        //算分函数
                                        ScoreFunctionBuilders.weightFactorFunction(10)
                                )
                });

        request.source().query(functionScoreQuery);
    }


    private PageResult handleResponse(SearchResponse response) {
        //4.解析响应
        SearchHits searchHits = response.getHits();
        //4.1获取总条数
        long total = searchHits.getTotalHits().value;
        //4.2文档数组
        SearchHit[] hits = searchHits.getHits();
        //4.3遍历
        List<HotelDoc> hotels = new ArrayList<>();
        for (SearchHit hit : hits){
            //获取文档source
            String json = hit.getSourceAsString();
            //反序列化
            HotelDoc hotelDoc = JSON.parseObject(json, HotelDoc.class);
            //获取排序值
            Object[] sortValues = hit.getSortValues();
            if (sortValues.length > 0 ){
                Object sortValue = sortValues[0];
                hotelDoc.setDistance(sortValue);
            }

            hotels.add(hotelDoc);
        }
        //4.4封装返回
        return new PageResult(total,hotels);
    }

}