Elasticsearch - 尚硅谷（4. Elasticsearch 基本操作_下）学习笔记
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文章目录
- 3.5 Java API 操作
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- 3.5.1 搭建环境
- 3.5.2 创建客户端对象
- 3.5.3 索引操作
- 3.5.4 文档操作
- 3.5.5 高级查询
3.5 Java API 操作
- Elasticsearch 软件是由 Java 语言开发的，所以也可以通过 Java API 的方式对 Elasticsearch
服务进行访问
3.5.1 搭建环境
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在 IDEA 中创建一个 Maven 依赖
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修改 Pom.xml
<dependencies> <dependency> <groupId>org.elasticsearchgroupId> <artifactId>elasticsearchartifactId> <version>7.8.0version> dependency> <dependency> <groupId>org.elasticsearch.clientgroupId> <artifactId>elasticsearch-rest-high-level-clientartifactId> <version>7.8.0version> dependency> <dependency> <groupId>org.apache.logging.log4jgroupId> <artifactId>log4j-apiartifactId> <version>2.8.2version> dependency> <dependency> <groupId>org.apache.logging.log4jgroupId> <artifactId>log4j-coreartifactId> <version>2.8.2version> dependency> <dependency> <groupId>com.fasterxml.jackson.coregroupId> <artifactId>jackson-databindartifactId> <version>2.9.9version> dependency> <dependency> <groupId>junitgroupId> <artifactId>junitartifactId> <version>4.12version> dependency> dependencies>
3.5.2 创建客户端对象
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新建一个类，并编写代码
public class ESTest_Client { public static void main(String[] args) throws Exception { // 创建ES客户端 RestHighLevelClient esClient = new RestHighLevelClient( RestClient.builder(new HttpHost("localhost", 9200, "http")) ); // 关闭ES客户端 esClient.close(); } }注意：9200 端口为 Elasticsearch 的 Web 通信端口，localhost 为启动 ES 服务的主机名
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启动测试
控制台没有报错就表示连接成功
3.5.3 索引操作
- ES 服务器正常启动后，可以通过 Java API 客户端对象对 ES 索引进行操作
- 创建索引
- 创建新的类，并编写
public class ESTest_Index_Create { public static void main(String[] args) throws Exception { RestHighLevelClient esClient = new RestHighLevelClient( RestClient.builder(new HttpHost("localhost", 9200, "http")) ); // 创建索引 CreateIndexRequest request = new CreateIndexRequest("user"); CreateIndexResponse createIndexResponse = esClient.indices().create(request, RequestOptions.DEFAULT); // 响应状态 boolean acknowledged = createIndexResponse.isAcknowledged(); System.out.println("索引操作 ：" + acknowledged); esClient.close(); } } - 启动测试
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查看索引
// 查询索引 GetIndexRequest request = new GetIndexRequest("user"); GetIndexResponse getIndexResponse = esClient.indices().get(request, RequestOptions.DEFAULT); // 响应状态 System.out.println(getIndexResponse.getAliases()); System.out.println(getIndexResponse.getMappings()); System.out.println(getIndexResponse.getSettings());允许测试
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删除索引
// 查询索引 DeleteIndexRequest request = new DeleteIndexRequest("user"); AcknowledgedResponse response = esClient.indices().delete(request, RequestOptions.DEFAULT); // 响应状态 System.out.println(response.isAcknowledged());允许测试
3.5.4 文档操作
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创建数据模型
public class User { private String name; private String sex; private Integer age; public String getName() { return name; } public void setName(String name) { this.name = name; } public String getSex() { return sex; } public void setSex(String sex) { this.sex = sex; } public Integer getAge() { return age; } public void setAge(Integer age) { this.age = age; } }
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新增文档
// 插入数据 IndexRequest request = new IndexRequest(); request.index("user").id("1001"); User user = new User(); user.setName("zhangsan"); user.setAge(30); user.setSex("男"); // 向ES插入数据，必须将数据转换位JSON格式 ObjectMapper mapper = new ObjectMapper(); String userJson = mapper.writeValueAsString(user); request.source(userJson, XContentType.JSON); IndexResponse response = esClient.index(request, RequestOptions.DEFAULT); System.out.println(response.getResult());运行测试
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修改文档
// 修改数据 UpdateRequest request = new UpdateRequest(); request.index("user").id("1001"); request.doc(XContentType.JSON, "sex", "女"); UpdateResponse response = esClient.update(request, RequestOptions.DEFAULT); System.out.println(response.getResult());运行测试
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查询文档
// 查询数据 GetRequest request = new GetRequest(); request.index("user").id("1001"); GetResponse response = esClient.get(request, RequestOptions.DEFAULT); System.out.println(response.getSourceAsString());运行测试
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删除文档
DeleteRequest request = new DeleteRequest(); request.index("user").id("1001"); DeleteResponse response = esClient.delete(request, RequestOptions.DEFAULT); System.out.println(response.toString());运行测试
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批量操作
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批量新增
// 批量插入数据 BulkRequest request = new BulkRequest(); request.add(new IndexRequest().index("user").id("1001").source(XContentType.JSON, "name", "zhangsan", "age",30,"sex","男")); request.add(new IndexRequest().index("user").id("1002").source(XContentType.JSON, "name", "lisi", "age",30,"sex","女")); request.add(new IndexRequest().index("user").id("1003").source(XContentType.JSON, "name", "wangwu", "age",40,"sex","男")); BulkResponse response = esClient.bulk(request, RequestOptions.DEFAULT); System.out.println(response.getTook()); System.out.println(response.getItems());运行测试
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批量删除
// 批量删除数据 BulkRequest request = new BulkRequest(); request.add(new DeleteRequest().index("user").id("1001")); request.add(new DeleteRequest().index("user").id("1002")); request.add(new DeleteRequest().index("user").id("1003")); BulkResponse response = esClient.bulk(request, RequestOptions.DEFAULT); System.out.println(response.getTook()); System.out.println(response.getItems());运行测试
3.5.5 高级查询
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查询所有索引数据
// 1. 查询索引中全部的数据 SearchRequest request = new SearchRequest(); request.indices("user"); request.source(new SearchSourceBuilder().query(QueryBuilders.matchAllQuery())); SearchResponse response = esClient.search(request, RequestOptions.DEFAULT); SearchHits hits = response.getHits(); System.out.println(hits.getTotalHits()); System.out.println(response.getTook()); for ( SearchHit hit : hits ) { System.out.println(hit.getSourceAsString()); }
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term 查询，查询条件为关键字
SearchRequest request = new SearchRequest(); request.indices("user"); request.source(new SearchSourceBuilder().query(QueryBuilders.termQuery("age", 30))); SearchResponse response = esClient.search(request, RequestOptions.DEFAULT); SearchHits hits = response.getHits(); System.out.println(hits.getTotalHits()); System.out.println(response.getTook()); for ( SearchHit hit : hits ) { System.out.println(hit.getSourceAsString()); }
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分页查询
SearchRequest request = new SearchRequest(); request.indices("user"); SearchSourceBuilder builder = new SearchSourceBuilder().query(QueryBuilders.matchAllQuery()); // (当前页码-1)*每页显示数据条数 builder.from(2); builder.size(2); request.source(builder); SearchResponse response = esClient.search(request, RequestOptions.DEFAULT); SearchHits hits = response.getHits(); System.out.println(hits.getTotalHits()); System.out.println(response.getTook()); for ( SearchHit hit : hits ) { System.out.println(hit.getSourceAsString()); }
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查询排序
SearchRequest request = new SearchRequest(); request.indices("user"); SearchSourceBuilder builder = new SearchSourceBuilder().query(QueryBuilders.matchAllQuery()); builder.sort("age", SortOrder.DESC); request.source(builder); SearchResponse response = esClient.search(request, RequestOptions.DEFAULT); SearchHits hits = response.getHits(); System.out.println(hits.getTotalHits()); System.out.println(response.getTook()); for ( SearchHit hit : hits ) { System.out.println(hit.getSourceAsString()); }
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过滤字段
SearchRequest request = new SearchRequest(); request.indices("user"); SearchSourceBuilder builder = new SearchSourceBuilder().query(QueryBuilders.matchAllQuery()); String[] excludes = { "age"}; String[] includes = { }; builder.fetchSource(includes, excludes); request.source(builder); SearchResponse response = esClient.search(request, RequestOptions.DEFAULT); SearchHits hits = response.getHits(); System.out.println(hits.getTotalHits()); System.out.println(response.getTook()); for ( SearchHit hit : hits ) { System.out.println(hit.getSourceAsString()); }
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组合查询
SearchRequest request = new SearchRequest(); request.indices("user"); SearchSourceBuilder builder = new SearchSourceBuilder(); BoolQueryBuilder boolQueryBuilder = QueryBuilders.boolQuery(); //boolQueryBuilder.must(QueryBuilders.matchQuery("age", 30)); //boolQueryBuilder.must(QueryBuilders.matchQuery("sex", "男")); //boolQueryBuilder.mustNot(QueryBuilders.matchQuery("sex", "男")); boolQueryBuilder.should(QueryBuilders.matchQuery("age", 30)); boolQueryBuilder.should(QueryBuilders.matchQuery("age", 40)); builder.query(boolQueryBuilder); request.source(builder); SearchResponse response = esClient.search(request, RequestOptions.DEFAULT); SearchHits hits = response.getHits(); System.out.println(hits.getTotalHits()); System.out.println(response.getTook()); for ( SearchHit hit : hits ) { System.out.println(hit.getSourceAsString()); }
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范围查询
SearchRequest request = new SearchRequest(); request.indices("user"); SearchSourceBuilder builder = new SearchSourceBuilder(); RangeQueryBuilder rangeQuery = QueryBuilders.rangeQuery("age"); rangeQuery.gte(30); rangeQuery.lt(50); builder.query(rangeQuery); request.source(builder); SearchResponse response = esClient.search(request, RequestOptions.DEFAULT); SearchHits hits = response.getHits(); System.out.println(hits.getTotalHits()); System.out.println(response.getTook()); for ( SearchHit hit : hits ) { System.out.println(hit.getSourceAsString()); }
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模糊查询
SearchRequest request = new SearchRequest(); request.indices("user"); SearchSourceBuilder builder = new SearchSourceBuilder(); builder.query(QueryBuilders.fuzzyQuery("name", "wangwu").fuzziness(Fuzziness.TWO)); request.source(builder); SearchResponse response = esClient.search(request, RequestOptions.DEFAULT); SearchHits hits = response.getHits(); System.out.println(hits.getTotalHits()); System.out.println(response.getTook()); for ( SearchHit hit : hits ) { System.out.println(hit.getSourceAsString()); }
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高亮查询
SearchRequest request = new SearchRequest(); request.indices("user"); SearchSourceBuilder builder = new SearchSourceBuilder(); TermsQueryBuilder termsQueryBuilder = QueryBuilders.termsQuery("name", "zhangsan"); HighlightBuilder highlightBuilder = new HighlightBuilder(); highlightBuilder.preTags(""); highlightBuilder.postTags(""); highlightBuilder.field("name"); builder.highlighter(highlightBuilder); builder.query(termsQueryBuilder); request.source(builder); SearchResponse response = esClient.search(request, RequestOptions.DEFAULT); SearchHits hits = response.getHits(); System.out.println(hits.getTotalHits()); System.out.println(response.getTook()); for ( SearchHit hit : hits ) { System.out.println(hit.getSourceAsString()); System.out.println(hit.getHighlightFields()); }
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聚合查询
SearchRequest request = new SearchRequest(); request.indices("user"); SearchSourceBuilder builder = new SearchSourceBuilder(); AggregationBuilder aggregationBuilder = AggregationBuilders.max("maxAge").field("age"); builder.aggregation(aggregationBuilder); request.source(builder); SearchResponse response = esClient.search(request, RequestOptions.DEFAULT); SearchHits hits = response.getHits(); System.out.println(hits.getTotalHits()); System.out.println(response.getTook()); for ( SearchHit hit : hits ) { System.out.println(hit.getSourceAsString()); }
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分组查询
SearchRequest request = new SearchRequest(); request.indices("user"); SearchSourceBuilder builder = new SearchSourceBuilder(); AggregationBuilder aggregationBuilder = AggregationBuilders.terms("ageGroup").field("age"); builder.aggregation(aggregationBuilder); request.source(builder); SearchResponse response = esClient.search(request, RequestOptions.DEFAULT); SearchHits hits = response.getHits(); System.out.println(hits.getTotalHits()); System.out.println(response.getTook()); for ( SearchHit hit : hits ) { System.out.println(hit.getSourceAsString()); }