ElasticSearch全文搜索引擎之查询API操作详解

一、简介

二、查询API详解

三、总结

一、简介

前面一篇文章已经总结一些索引和文档相关的操作API，本篇文章将介绍Java客户端中如何查询搜索引擎中的数据，同样查询API也是基于RestHighLevelClient实现。

二、查询API详解

es查询API使用大体步骤：

构造SearchRequest查询请求对象，支持设置超时时间等信息；创建SeachRequest，如果没有传参数，这将针对所有索引运行。如果传了有参数，则按参数所传值为索引，此处“student_info”为索引库名称，大多数搜索参数都添加到SearchSourceBuilder中，它为搜索请求body中的所有内容提供了setter；
构造QueryBuilder对象，常见的QueryBuilder有BoolQueryBuilder、MatchQueryBuilder、RangeQueryBuilder等；
构造SearchSourceBuilder对象，调用searchSourceBuilder.query(xxxQueryBuilder)方法； //设置查询，可以是任何类型的QueryBuilder。
调用searchRequest.source(searchSourceBuilder)方法； //将SearchSourceBuilder添加到SeachRequest。
执行查询请求，restHighLevelClient.search(searchRequest, RequestOptions.DEFAULT)；
获取响应结果并解析；

RestHighLevelClient查询ES中数据的API主要有：must、match_all、match、should、range、order等等。

search查询的主要参数是SearchRequest，我们的查询条件index、type、字段、字段值都封装在SearchRequest中；

而index、type是直接封装在SearchRequest的对象中，查询的字段、字段值、查询方式则封装在SearchRequest中的对象属性SearchSourceBuilder中；

下面通过几个常见的查询示例说明如何通过RestHighLevelClient查询es索引中数据。

【a】match_all全部匹配搜索

QueryBuilders.matchAllQuery()

/*** match_all全部匹配搜索: QueryBuilders.matchAllQuery()*/@Testvoid matchAllSearch() throws IOException {SearchRequest searchRequest = new SearchRequest("student_info");//构建搜索条件SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();//全部匹配查询MatchAllQueryBuilder matchAllQueryBuilder = QueryBuilders.matchAllQuery();searchSourceBuilder.query(matchAllQueryBuilder);//设置超时时间searchSourceBuilder.timeout(new TimeValue(60, TimeUnit.SECONDS));searchRequest.source(searchSourceBuilder);SearchResponse response = null;try {//执行查询请求,获取响应结果response = restHighLevelClient.search(searchRequest, RequestOptions.DEFAULT);} catch (IOException e) {e.printStackTrace();}//循环遍历查询结果System.out.println(JSON.toJSONString(response.getHits()));for (SearchHit documentFields : response.getHits().getHits()) {System.out.println(documentFields.getSourceAsMap());}restHighLevelClient.close();}

控制台日志如下：

{"fragment":true,"hits":[{"fields":{},"fragment":false,"highlightFields":{},"id":"1","matchedQueries":[],"primaryTerm":0,"rawSortValues":[],"score":1.0,"seqNo":-2,"sortValues":[],"sourceAsMap":{"name":"张三","age":10},"sourceAsString":"{\"age\":10,\"name\":\"张三\"}","sourceRef":{"fragment":true},"type":"_doc","version":-1},{"fields":{},"fragment":false,"highlightFields":{},"id":"2","matchedQueries":[],"primaryTerm":0,"rawSortValues":[],"score":1.0,"seqNo":-2,"sortValues":[],"sourceAsMap":{"name":"李四","age":20},"sourceAsString":"{\"age\":20,\"name\":\"李四\"}","sourceRef":{"fragment":true},"type":"_doc","version":-1},{"fields":{},"fragment":false,"highlightFields":{},"id":"3","matchedQueries":[],"primaryTerm":0,"rawSortValues":[],"score":1.0,"seqNo":-2,"sortValues":[],"sourceAsMap":{"name":"王五","age":30},"sourceAsString":"{\"age\":30,\"name\":\"王五\"}","sourceRef":{"fragment":true},"type":"_doc","version":-1},{"fields":{},"fragment":false,"highlightFields":{},"id":"4","matchedQueries":[],"primaryTerm":0,"rawSortValues":[],"score":1.0,"seqNo":-2,"sortValues":[],"sourceAsMap":{"name":"赵六","age":40},"sourceAsString":"{\"age\":40,\"name\":\"赵六\"}","sourceRef":{"fragment":true},"type":"_doc","version":-1},{"fields":{},"fragment":false,"highlightFields":{},"id":"5","matchedQueries":[],"primaryTerm":0,"rawSortValues":[],"score":1.0,"seqNo":-2,"sortValues":[],"sourceAsMap":{"name":"田七","age":50},"sourceAsString":"{\"age\":50,\"name\":\"田七\"}","sourceRef":{"fragment":true},"type":"_doc","version":-1}],"maxScore":1.0,"totalHits":{"relation":"EQUAL_TO","value":5}}
{name=张三, age=10}
{name=李四, age=20}
{name=王五, age=30}
{name=赵六, age=40}
{name=田七, age=50}

【b】只返回特定字段

searchSourceBuilder.fetchSource("name", "age")

通常使用下面两种方法（任意一种）设置查询返回的字段集合，方法还接受一个或多个通配符模式的数组，以控制以更精细的方式包含或排除哪些字段。第一个是获取的字段，第二个是过滤的字段，默认获取全部。

public SearchSourceBuilder fetchSource(@Nullable String include, @Nullable String exclude) {return this.fetchSource(include == null ? Strings.EMPTY_ARRAY : new String[]{include}, exclude == null ? Strings.EMPTY_ARRAY : new String[]{exclude});}public SearchSourceBuilder fetchSource(@Nullable String[] includes, @Nullable String[] excludes) {FetchSourceContext fetchSourceContext = this.fetchSourceContext != null ? this.fetchSourceContext : FetchSourceContext.FETCH_SOURCE;this.fetchSourceContext = new FetchSourceContext(fetchSourceContext.fetchSource(), includes, excludes);return this;}

/*** 只返回特定字段: searchSourceBuilder.fetchSource("name", "age")*/@Testvoid notAllFieldsSearch() throws IOException {SearchRequest searchRequest = new SearchRequest("student_info");//构建搜索条件SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();//全部匹配查询MatchAllQueryBuilder matchAllQueryBuilder = QueryBuilders.matchAllQuery();searchSourceBuilder.query(matchAllQueryBuilder);//设置超时时间searchSourceBuilder.timeout(new TimeValue(60, TimeUnit.SECONDS));//只返回name字段，排除age字段searchSourceBuilder.fetchSource("name", "age");searchRequest.source(searchSourceBuilder);SearchResponse response = null;try {//执行查询请求,获取响应结果response = restHighLevelClient.search(searchRequest, RequestOptions.DEFAULT);} catch (IOException e) {e.printStackTrace();}//循环遍历查询结果System.out.println(JSON.toJSONString(response.getHits()));for (SearchHit documentFields : response.getHits().getHits()) {System.out.println(documentFields.getSourceAsMap());}restHighLevelClient.close();}

控制台日志如下：

{"fragment":true,"hits":[{"fields":{},"fragment":false,"highlightFields":{},"id":"1","matchedQueries":[],"primaryTerm":0,"rawSortValues":[],"score":1.0,"seqNo":-2,"sortValues":[],"sourceAsMap":{"name":"张三"},"sourceAsString":"{\"name\":\"张三\"}","sourceRef":{"fragment":true},"type":"_doc","version":-1},{"fields":{},"fragment":false,"highlightFields":{},"id":"2","matchedQueries":[],"primaryTerm":0,"rawSortValues":[],"score":1.0,"seqNo":-2,"sortValues":[],"sourceAsMap":{"name":"李四"},"sourceAsString":"{\"name\":\"李四\"}","sourceRef":{"fragment":true},"type":"_doc","version":-1},{"fields":{},"fragment":false,"highlightFields":{},"id":"3","matchedQueries":[],"primaryTerm":0,"rawSortValues":[],"score":1.0,"seqNo":-2,"sortValues":[],"sourceAsMap":{"name":"王五"},"sourceAsString":"{\"name\":\"王五\"}","sourceRef":{"fragment":true},"type":"_doc","version":-1},{"fields":{},"fragment":false,"highlightFields":{},"id":"4","matchedQueries":[],"primaryTerm":0,"rawSortValues":[],"score":1.0,"seqNo":-2,"sortValues":[],"sourceAsMap":{"name":"赵六"},"sourceAsString":"{\"name\":\"赵六\"}","sourceRef":{"fragment":true},"type":"_doc","version":-1},{"fields":{},"fragment":false,"highlightFields":{},"id":"5","matchedQueries":[],"primaryTerm":0,"rawSortValues":[],"score":1.0,"seqNo":-2,"sortValues":[],"sourceAsMap":{"name":"田七"},"sourceAsString":"{\"name\":\"田七\"}","sourceRef":{"fragment":true},"type":"_doc","version":-1}],"maxScore":1.0,"totalHits":{"relation":"EQUAL_TO","value":5}}
{name=张三}
{name=李四}
{name=王五}
{name=赵六}
{name=田七}

【c】match模糊搜索

QueryBuilders.matchQuery("name", "张")

/*** match模糊搜索: QueryBuilders.matchQuery("name", "张")* 查询name字段中包含"张"的记录*/@Testvoid matchSearch() throws IOException {SearchRequest searchRequest = new SearchRequest("student_info");//构建搜索条件SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();//查询name字段中包含"张"的记录MatchQueryBuilder matchQueryBuilder = QueryBuilders.matchQuery("name", "张");searchSourceBuilder.query(matchQueryBuilder);//设置超时时间searchSourceBuilder.timeout(new TimeValue(60, TimeUnit.SECONDS));searchRequest.source(searchSourceBuilder);SearchResponse response = null;try {//执行查询请求,获取响应结果response = restHighLevelClient.search(searchRequest, RequestOptions.DEFAULT);} catch (IOException e) {e.printStackTrace();}//循环遍历查询结果System.out.println(JSON.toJSONString(response.getHits()));for (SearchHit documentFields : response.getHits().getHits()) {System.out.println(documentFields.getSourceAsMap());}restHighLevelClient.close();}

控制台日志如下：

{"fragment":true,"hits":[{"fields":{},"fragment":false,"highlightFields":{},"id":"1","matchedQueries":[],"primaryTerm":0,"rawSortValues":[],"score":1.3862942,"seqNo":-2,"sortValues":[],"sourceAsMap":{"name":"张三","age":10},"sourceAsString":"{\"age\":10,\"name\":\"张三\"}","sourceRef":{"fragment":true},"type":"_doc","version":-1}],"maxScore":1.3862942,"totalHits":{"relation":"EQUAL_TO","value":1}}
{name=张三, age=10}

【d】term精确搜索

QueryBuilders.termQuery("name", "张")

/*** term精确搜索*/@Testvoid termSearch() throws IOException {SearchRequest searchRequest = new SearchRequest("student_info");//构建搜索条件SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();//精确查询  name精确匹配"张"的记录TermQueryBuilder termQueryBuilder = QueryBuilders.termQuery("name", "张");searchSourceBuilder.query(termQueryBuilder);//设置超时时间searchSourceBuilder.timeout(new TimeValue(60, TimeUnit.SECONDS));searchRequest.source(searchSourceBuilder);SearchResponse response = null;try {//执行查询请求,获取响应结果response = restHighLevelClient.search(searchRequest, RequestOptions.DEFAULT);} catch (IOException e) {e.printStackTrace();}//循环遍历查询结果System.out.println(JSON.toJSONString(response.getHits()));for (SearchHit documentFields : response.getHits().getHits()) {System.out.println(documentFields.getSourceAsMap());}restHighLevelClient.close();}

控制台日志如下：

{"fragment":true,"hits":[{"fields":{},"fragment":false,"highlightFields":{},"id":"1","matchedQueries":[],"primaryTerm":0,"rawSortValues":[],"score":1.3862942,"seqNo":-2,"sortValues":[],"sourceAsMap":{"name":"张三","age":10},"sourceAsString":"{\"age\":10,\"name\":\"张三\"}","sourceRef":{"fragment":true},"type":"_doc","version":-1}],"maxScore":1.3862942,"totalHits":{"relation":"EQUAL_TO","value":1}}
{name=张三, age=10}

【e】范围查询

QueryBuilders.rangeQuery("age")

/*** 范围查询*/@Testvoid rangeSearch() throws IOException {SearchRequest searchRequest = new SearchRequest("student_info");SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();//构建bool查询BoolQueryBuilder boolQueryBuilder = new BoolQueryBuilder();//年龄大于等于20,小于等于40的记录boolQueryBuilder.must(QueryBuilders.rangeQuery("age")  //指定范围查询的字段.gte("20").lte("50"));searchSourceBuilder.query(boolQueryBuilder);searchRequest.source(searchSourceBuilder);SearchResponse response = null;try {response = restHighLevelClient.search(searchRequest, RequestOptions.DEFAULT);} catch (IOException e) {e.printStackTrace();}//循环遍历查询结果System.out.println(JSON.toJSONString(response.getHits()));for (SearchHit documentFields : response.getHits().getHits()) {System.out.println(documentFields.getSourceAsMap());}restHighLevelClient.close();}

控制台日志如下：

{"fragment":true,"hits":[{"fields":{},"fragment":false,"highlightFields":{},"id":"2","matchedQueries":[],"primaryTerm":0,"rawSortValues":[],"score":1.0,"seqNo":-2,"sortValues":[],"sourceAsMap":{"name":"李四","age":20},"sourceAsString":"{\"age\":20,\"name\":\"李四\"}","sourceRef":{"fragment":true},"type":"_doc","version":-1},{"fields":{},"fragment":false,"highlightFields":{},"id":"3","matchedQueries":[],"primaryTerm":0,"rawSortValues":[],"score":1.0,"seqNo":-2,"sortValues":[],"sourceAsMap":{"name":"王五","age":30},"sourceAsString":"{\"age\":30,\"name\":\"王五\"}","sourceRef":{"fragment":true},"type":"_doc","version":-1},{"fields":{},"fragment":false,"highlightFields":{},"id":"4","matchedQueries":[],"primaryTerm":0,"rawSortValues":[],"score":1.0,"seqNo":-2,"sortValues":[],"sourceAsMap":{"name":"赵六","age":40},"sourceAsString":"{\"age\":40,\"name\":\"赵六\"}","sourceRef":{"fragment":true},"type":"_doc","version":-1},{"fields":{},"fragment":false,"highlightFields":{},"id":"5","matchedQueries":[],"primaryTerm":0,"rawSortValues":[],"score":1.0,"seqNo":-2,"sortValues":[],"sourceAsMap":{"name":"田七","age":50},"sourceAsString":"{\"age\":50,\"name\":\"田七\"}","sourceRef":{"fragment":true},"type":"_doc","version":-1}],"maxScore":1.0,"totalHits":{"relation":"EQUAL_TO","value":4}}
{name=李四, age=20}
{name=王五, age=30}
{name=赵六, age=40}
{name=田七, age=50}

【f】must与查询(相当于and)

must表示符合条件的，相反的mustnot表示不符合条件的。

/*** must与查询(相当于and)*/@Testvoid mustQuery() {//构造查询请求SearchRequest searchRequest = new SearchRequest("student_info");//构造SearchSourceBuilderSearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();//构造bool查询BoolQueryBuilder boolQueryBuilder = QueryBuilders.boolQuery();/*** must: and且查询* select * from xxx where name (like '%张%' ) and (age >= 10 and age <= 20)*///1.范围查询: 年龄大于等于10、小于等于20的记录RangeQueryBuilder rangeQueryBuilder = QueryBuilders.rangeQuery("age");rangeQueryBuilder.lte(20).gte(10);boolQueryBuilder.must(rangeQueryBuilder);//2.match匹配查询: 姓名中包含"张"的记录MatchQueryBuilder matchQueryBuilder = QueryBuilders.matchQuery("name", "张");boolQueryBuilder.must(matchQueryBuilder);searchSourceBuilder.query(boolQueryBuilder);searchRequest.source(searchSourceBuilder);SearchResponse response = null;try {//执行请求，返回响应结果response = restHighLevelClient.search(searchRequest, RequestOptions.DEFAULT);} catch (IOException e) {e.printStackTrace();}System.out.println(JSON.toJSONString(response.getHits()));for (SearchHit searchHit : response.getHits().getHits()) {System.out.println(searchHit.getSourceAsMap());}}

控制台日志如下：

{"fragment":true,"hits":[{"fields":{},"fragment":false,"highlightFields":{},"id":"1","matchedQueries":[],"primaryTerm":0,"rawSortValues":[],"score":2.3862944,"seqNo":-2,"sortValues":[],"sourceAsMap":{"name":"张三","age":10},"sourceAsString":"{\"age\":10,\"name\":\"张三\"}","sourceRef":{"fragment":true},"type":"_doc","version":-1}],"maxScore":2.3862944,"totalHits":{"relation":"EQUAL_TO","value":1}}
{name=张三, age=10}

【g】should或查询(相当于or)

/*** should或查询(相当于or)*/@Testvoid shouldQuery() {//构造查询请求SearchRequest searchRequest = new SearchRequest("student_info");//构造SearchSourceBuilderSearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();//构造bool查询BoolQueryBuilder boolQueryBuilder = QueryBuilders.boolQuery();/*** should: or或查询* select * from xxx where name (like '%张%' ) or (age >= 10 and age <= 20)*///1.范围查询: 年龄大于等于10、小于等于20的记录RangeQueryBuilder rangeQueryBuilder = QueryBuilders.rangeQuery("age");rangeQueryBuilder.lte(20).gte(10);boolQueryBuilder.should(rangeQueryBuilder);//2.match匹配查询: 姓名中包含"张"的记录MatchQueryBuilder matchQueryBuilder = QueryBuilders.matchQuery("name", "张");boolQueryBuilder.should(matchQueryBuilder);searchSourceBuilder.query(boolQueryBuilder);searchRequest.source(searchSourceBuilder);SearchResponse response = null;try {//执行请求，返回响应结果response = restHighLevelClient.search(searchRequest, RequestOptions.DEFAULT);} catch (IOException e) {e.printStackTrace();}System.out.println(JSON.toJSONString(response.getHits()));for (SearchHit searchHit : response.getHits().getHits()) {System.out.println(searchHit.getSourceAsMap());}}

控制台日志如下：

{"fragment":true,"hits":[{"fields":{},"fragment":false,"highlightFields":{},"id":"1","matchedQueries":[],"primaryTerm":0,"rawSortValues":[],"score":2.3862944,"seqNo":-2,"sortValues":[],"sourceAsMap":{"name":"张三","age":10},"sourceAsString":"{\"age\":10,\"name\":\"张三\"}","sourceRef":{"fragment":true},"type":"_doc","version":-1},{"fields":{},"fragment":false,"highlightFields":{},"id":"2","matchedQueries":[],"primaryTerm":0,"rawSortValues":[],"score":1.0,"seqNo":-2,"sortValues":[],"sourceAsMap":{"name":"李四","age":20},"sourceAsString":"{\"age\":20,\"name\":\"李四\"}","sourceRef":{"fragment":true},"type":"_doc","version":-1}],"maxScore":2.3862944,"totalHits":{"relation":"EQUAL_TO","value":2}}
{name=张三, age=10}
{name=李四, age=20}

【h】带排序的搜索

SearchSourceBuilder的排序：允许添加一个或多个SortBuilder实例，有四种特殊的实现（Field-，Score-，GeoDistance-和ScriptSortBuilder）。

sourceBuilder.sort(new ScoreSortBuilder().order(SortOrder.DESC)); //按_score降序排序（默认值）
sourceBuilder.sort(new FieldSortBuilder("_id").order(SortOrder.ASC)); //按_id字段进行升序排序

searchSourceBuilder.sort("age", SortOrder.DESC);

/*** 带排序的搜索: searchSourceBuilder.sort("age", SortOrder.DESC);*/@Testvoid sortQuery() throws IOException {SearchRequest searchRequest = new SearchRequest("student_info");//构建搜索条件SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();MatchAllQueryBuilder matchAllQueryBuilder = QueryBuilders.matchAllQuery();searchSourceBuilder.query(matchAllQueryBuilder);//设置超时时间searchSourceBuilder.timeout(new TimeValue(60, TimeUnit.SECONDS));//按age降序排序searchSourceBuilder.sort("age", SortOrder.DESC);searchRequest.source(searchSourceBuilder);SearchResponse response = null;try {//执行查询请求,获取响应结果response = restHighLevelClient.search(searchRequest, RequestOptions.DEFAULT);} catch (IOException e) {e.printStackTrace();}//循环遍历查询结果System.out.println(JSON.toJSONString(response.getHits()));for (SearchHit documentFields : response.getHits().getHits()) {System.out.println(documentFields.getSourceAsMap());}restHighLevelClient.close();}

控制台日志如下：

{"fragment":true,"hits":[{"fields":{},"fragment":false,"highlightFields":{},"id":"5","matchedQueries":[],"primaryTerm":0,"rawSortValues":[],"score":null,"seqNo":-2,"sortValues":[50],"sourceAsMap":{"name":"田七","age":50},"sourceAsString":"{\"age\":50,\"name\":\"田七\"}","sourceRef":{"fragment":true},"type":"_doc","version":-1},{"fields":{},"fragment":false,"highlightFields":{},"id":"4","matchedQueries":[],"primaryTerm":0,"rawSortValues":[],"score":null,"seqNo":-2,"sortValues":[40],"sourceAsMap":{"name":"赵六","age":40},"sourceAsString":"{\"age\":40,\"name\":\"赵六\"}","sourceRef":{"fragment":true},"type":"_doc","version":-1},{"fields":{},"fragment":false,"highlightFields":{},"id":"3","matchedQueries":[],"primaryTerm":0,"rawSortValues":[],"score":null,"seqNo":-2,"sortValues":[30],"sourceAsMap":{"name":"王五","age":30},"sourceAsString":"{\"age\":30,\"name\":\"王五\"}","sourceRef":{"fragment":true},"type":"_doc","version":-1},{"fields":{},"fragment":false,"highlightFields":{},"id":"2","matchedQueries":[],"primaryTerm":0,"rawSortValues":[],"score":null,"seqNo":-2,"sortValues":[20],"sourceAsMap":{"name":"李四","age":20},"sourceAsString":"{\"age\":20,\"name\":\"李四\"}","sourceRef":{"fragment":true},"type":"_doc","version":-1},{"fields":{},"fragment":false,"highlightFields":{},"id":"1","matchedQueries":[],"primaryTerm":0,"rawSortValues":[],"score":null,"seqNo":-2,"sortValues":[10],"sourceAsMap":{"name":"张三","age":10},"sourceAsString":"{\"age\":10,\"name\":\"张三\"}","sourceRef":{"fragment":true},"type":"_doc","version":-1}],"maxScore":null,"totalHits":{"relation":"EQUAL_TO","value":5}}
{name=田七, age=50}
{name=赵六, age=40}
{name=王五, age=30}
{name=李四, age=20}
{name=张三, age=10}

【i】分页搜索

searchSourceBuilder.from(1); //设置确定结果要从哪个索引开始搜索的from选项，默认为0
searchSourceBuilder.size(2); //设置确定搜素命中返回数的size选项，默认为10

/*** 分页搜索: searchSourceBuilder.from(1);  searchSourceBuilder.size(2);*/@Testvoid paginationQuery() throws IOException {SearchRequest searchRequest = new SearchRequest("student_info");//构建搜索条件SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();MatchAllQueryBuilder matchAllQueryBuilder = QueryBuilders.matchAllQuery();searchSourceBuilder.query(matchAllQueryBuilder);//设置超时时间searchSourceBuilder.timeout(new TimeValue(60, TimeUnit.SECONDS));//按age降序排序searchSourceBuilder.sort("age", SortOrder.DESC);//从第一条记录开始，每页展示两条searchSourceBuilder.from(1);searchSourceBuilder.size(2);searchRequest.source(searchSourceBuilder);SearchResponse response = null;try {//执行查询请求,获取响应结果response = restHighLevelClient.search(searchRequest, RequestOptions.DEFAULT);} catch (IOException e) {e.printStackTrace();}//循环遍历查询结果System.out.println(JSON.toJSONString(response.getHits()));for (SearchHit documentFields : response.getHits().getHits()) {System.out.println(documentFields.getSourceAsMap());}restHighLevelClient.close();}

控制台日志如下：

{"fragment":true,"hits":[{"fields":{},"fragment":false,"highlightFields":{},"id":"4","matchedQueries":[],"primaryTerm":0,"rawSortValues":[],"score":null,"seqNo":-2,"sortValues":[40],"sourceAsMap":{"name":"赵六","age":40},"sourceAsString":"{\"age\":40,\"name\":\"赵六\"}","sourceRef":{"fragment":true},"type":"_doc","version":-1},{"fields":{},"fragment":false,"highlightFields":{},"id":"3","matchedQueries":[],"primaryTerm":0,"rawSortValues":[],"score":null,"seqNo":-2,"sortValues":[30],"sourceAsMap":{"name":"王五","age":30},"sourceAsString":"{\"age\":30,\"name\":\"王五\"}","sourceRef":{"fragment":true},"type":"_doc","version":-1}],"maxScore":null,"totalHits":{"relation":"EQUAL_TO","value":5}}
{name=赵六, age=40}
{name=王五, age=30}

【j】高亮搜索

通过在SearchSourceBuilder上设置HighlightBuilder，可以实现高亮搜索结果。

HighlightBuilder highlightBuilder = new HighlightBuilder();
highlightBuilder.field("name");
highlightBuilder.preTags("<span style=\"color:red\">");
highlightBuilder.postTags("</span>");
searchSourceBuilder.highlighter(highlightBuilder);

/*** 高亮显示搜索*/@Testvoid highLightQuery() throws IOException {SearchRequest searchRequest = new SearchRequest("student_info");//构建搜索条件SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();MatchQueryBuilder matchQueryBuilder = QueryBuilders.matchQuery("name", "张");//设置超时时间searchSourceBuilder.timeout(new TimeValue(60, TimeUnit.SECONDS));//按age降序排序searchSourceBuilder.sort("age", SortOrder.DESC);HighlightBuilder highlightBuilder = new HighlightBuilder();//指定高亮字段highlightBuilder.field("name");//指定前置标签highlightBuilder.preTags("<span style=\"color:red\">");//指定后置标签highlightBuilder.postTags("</span>");searchSourceBuilder.highlighter(highlightBuilder);searchSourceBuilder.query(matchQueryBuilder);searchRequest.source(searchSourceBuilder);SearchResponse response = null;try {//执行查询请求,获取响应结果response = restHighLevelClient.search(searchRequest, RequestOptions.DEFAULT);} catch (IOException e) {e.printStackTrace();}//循环遍历查询结果System.out.println(JSON.toJSONString(response.getHits()));for (SearchHit searchHit : response.getHits().getHits()) {Map<String, Object> sourceAsMap = searchHit.getSourceAsMap();//获取对应的高亮域Map<String, HighlightField> highlightFields = searchHit.getHighlightFields();//获取高亮字段HighlightField name = highlightFields.get("name");if (null != name) {// 为name串值增加自定义的高亮标签Text[] nameTexts = name.fragments();StringBuilder newName = new StringBuilder();for (Text text : nameTexts) {newName.append(text);}//将追加了高亮标签的串值重新填充到对应的对象sourceAsMap.put("name", newName.toString());}System.out.println(sourceAsMap);}restHighLevelClient.close();}

控制台日志输出：

{"fragment":true,"hits":[{"fields":{},"fragment":false,"highlightFields":{"name":{"fragment":true,"fragments":[{"fragment":true}],"name":"name"}},"id":"1","matchedQueries":[],"primaryTerm":0,"rawSortValues":[],"score":null,"seqNo":-2,"sortValues":[10],"sourceAsMap":{"name":"张三","age":10},"sourceAsString":"{\"age\":10,\"name\":\"张三\"}","sourceRef":{"fragment":true},"type":"_doc","version":-1}],"maxScore":null,"totalHits":{"relation":"EQUAL_TO","value":1}}
{name=<span style="color:red">张</span>三, age=10}

【k】一次查询多个条件

MultiSearchRequest multiSearchRequest = new MultiSearchRequest();
restHighLevelClient.msearch(multiSearchRequest, RequestOptions.DEFAULT)

  /*** 一次查询多个条件: restHighLevelClient.msearch(multiSearchRequest, RequestOptions.DEFAULT)*/@Testvoid multiSearchQuery() throws IOException {//构造请求MultiSearchRequestMultiSearchRequest multiSearchRequest = new MultiSearchRequest();/** 第一个SearchRequest*/SearchRequest firstSearchRequest = new SearchRequest("student_info");SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();MatchQueryBuilder matchQueryBuilder = QueryBuilders.matchQuery("name", "张");searchSourceBuilder.query(matchQueryBuilder);firstSearchRequest.source(searchSourceBuilder);multiSearchRequest.add(firstSearchRequest);/** 第二个SearchRequest*/SearchRequest secondSearchRequest = new SearchRequest("student_info");searchSourceBuilder = new SearchSourceBuilder();matchQueryBuilder = QueryBuilders.matchQuery("name", "李");searchSourceBuilder.query(matchQueryBuilder);secondSearchRequest.source(searchSourceBuilder);multiSearchRequest.add(secondSearchRequest);MultiSearchResponse multiSearchResponse;try {//执行请求，返回多个响应multiSearchResponse = restHighLevelClient.msearch(multiSearchRequest, RequestOptions.DEFAULT);multiSearchResponse.forEach(t -> {SearchResponse response = t.getResponse();//循环遍历查询结果System.out.println(JSON.toJSONString(response.getHits()));for (SearchHit searchHit : response.getHits().getHits()) {System.out.println(searchHit.getSourceAsMap());}});} catch (IOException e) {e.printStackTrace();}restHighLevelClient.close();}

控制台日志输出：

{"fragment":true,"hits":[{"fields":{},"fragment":false,"highlightFields":{},"id":"1","matchedQueries":[],"primaryTerm":0,"rawSortValues":[],"score":1.3862942,"seqNo":-2,"sortValues":[],"sourceAsMap":{"name":"张三","age":10},"sourceAsString":"{\"age\":10,\"name\":\"张三\"}","sourceRef":{"fragment":true},"type":"_doc","version":-1}],"maxScore":1.3862942,"totalHits":{"relation":"EQUAL_TO","value":1}}
{name=张三, age=10}
{"fragment":true,"hits":[{"fields":{},"fragment":false,"highlightFields":{},"id":"2","matchedQueries":[],"primaryTerm":0,"rawSortValues":[],"score":1.3862942,"seqNo":-2,"sortValues":[],"sourceAsMap":{"name":"李四","age":20},"sourceAsString":"{\"age\":20,\"name\":\"李四\"}","sourceRef":{"fragment":true},"type":"_doc","version":-1}],"maxScore":1.3862942,"totalHits":{"relation":"EQUAL_TO","value":1}}
{name=李四, age=20}

三、总结

以上总结了一些常见的ES Java客户端查询API相关的示例，在实际项目中，得根据具体的业务需求，灵活构造不同的xxxQueryBuilder实现。希望以上代码可以帮助到读者，也能为以后再次使用时提供帮助。由于笔者水平有限，以上如有不对之处，还望指正，相互学习，一起进步！