RestClient查询

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快速入门

我们通过match_all查询所有的文档内容来演示下基本的API,先看请求的DSL的组织

 @Test
    void testMatchAll() throws Exception{
        //1.准备Request
        SearchRequest searchRequest = new SearchRequest("hotel");
        //2.组织DSL参数
        searchRequest.source().query(QueryBuilders.matchAllQuery());
        SearchResponse search = client.search(searchRequest, RequestOptions.DEFAULT);
        System.out.println(search);

    }

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GET /hotel/_search
{
  "query":{
    "match_all": {}
  }
}

searchRequest.source()用来做为dsl的query字段，QueryBuilders用来调用各种查询条件

全文检索查询

全文检索的match和multi_match查询与match_all的API基本一致。差别是查询条件，也就是query的部分。

// 单字段查询
QueryBuilders.matchQuery("all","如家");
//多字段查询
QueryBuilders.multiMatchQuery("如家","name","business");

小tips:ctrl+alt+m 抽取公共方法

//复合查询-Boolean query 
//精确查询常见的有term查询和range查询，同样利用QueryBuilders实现：
//创建布尔查询
SearchRequest searchRequest = new SearchRequest("hotel");
BoolQueryBuilder boolQueryBuilder = QueryBuilders.boolQuery();
boolQueryBuilder.must(QueryBuilders.termQuery("city","北京"));
boolQueryBuilder.filter(QueryBuilders.rangeQuery("price").lte(500));
//2.组织DSL参数
searchRequest.source().query(boolQueryBuilder);

排序和分页

搜索结果的排序和分页是与query同级的参数，对应的API如下

 	@Test
    void testSort() throws Exception {
        //1.准备Request
        SearchRequest searchRequest = new SearchRequest("hotel");
        BoolQueryBuilder boolQueryBuilder = QueryBuilders.boolQuery();
        boolQueryBuilder.must(QueryBuilders.termQuery("city","北京"));
        boolQueryBuilder.filter(QueryBuilders.rangeQuery("price").gte(1000));
        //2.组织DSL参数
        searchRequest.source().query(boolQueryBuilder).sort("price",SortOrder.DESC).from(0).size(5);
        handleResponse(searchRequest);
    }

高亮

高亮API包括请求DSL构建和结果解析两部分。我们先看请求的DSL构建

//2.组织DSL参数
        searchRequest.source().query(boolQueryBuilder).sort("price",SortOrder.DESC).from(0).size(5).highlighter(
                new HighlightBuilder().field("name").requireFieldMatch(false)