Elasticsearch-核心篇(8)-JavaApi集成查询

r囧r小猫 2022-09-07 05:50 234阅读 0赞

### 文章目录 ###

*  一、Elasticsearch依赖
 *   *  1.1 Maven依赖
     *  1.2 公共方法
 *  二、Elasticsearch测试
 *   *  2.1 服务连接
     *  2.2 索引操作
     *  2.3 文档操作

参考文档： [https://www.elastic.co/guide/en/elasticsearch/client/java-rest/7.x/java-rest-high-create-index.html][https_www.elastic.co_guide_en_elasticsearch_client_java-rest_7.x_java-rest-high-create-index.html]

# 一、Elasticsearch依赖 #

## 1.1 Maven依赖 ##

*  elasticsearch-rest-high-level-client，高级REST客户端对象

<dependencies>
      <dependency>
        <groupId>junit</groupId>
        <artifactId>junit</artifactId>
        <version>4.13</version>
      </dependency>
      <dependency>
        <groupId>com.alibaba</groupId>
        <artifactId>fastjson</artifactId>
        <version>1.2.74</version>
      </dependency>
      <dependency>
        <groupId>org.projectlombok</groupId>
        <artifactId>lombok</artifactId>
        <version>1.18.18</version>
      </dependency>
    
      
      <dependency>
        <groupId>org.elasticsearch</groupId>
        <artifactId>elasticsearch</artifactId>
        <version>7.8.0</version>
      </dependency>
      
      <dependency>
        <groupId>org.elasticsearch.client</groupId>
        <artifactId>elasticsearch-rest-high-level-client</artifactId>
        <version>7.8.0</version>
      </dependency>
    </dependencies>

## 1.2 公共方法 ##

*  json美化工具类

import com.alibaba.fastjson.JSONObject;
    import lombok.AllArgsConstructor;
    import lombok.Getter;
    import lombok.NoArgsConstructor;
    import lombok.Setter;
    
    @Getter
    @Setter
    @NoArgsConstructor
    @AllArgsConstructor
    public class EsUser { 
        private String name;
        private Integer age;
        private String sex;
    
        public String toJsonString() { 
            return JSONObject.toJSONString(this);
        }
    }

# 二、Elasticsearch测试 #

## 2.1 服务连接 ##

*  RestHighLevelClient：高级客户端

import java.io.IOException;
    import java.util.Objects;
    import org.apache.http.HttpHost;
    import org.elasticsearch.client.RestClient;
    import org.elasticsearch.client.RestHighLevelClient;
    import org.junit.After;
    import org.junit.Before;
    
    public class ElasticsearchTest { 
        /** * 连接客户端 */
        private RestHighLevelClient client;
    
        @Before
        public void init() { 
            HttpHost serverHost = new HttpHost("127.0.0.1", 9200);
            client = new RestHighLevelClient(RestClient.builder(serverHost));
        }
    
        @After
        public void destroy() { 
            if (Objects.nonNull(client)) { 
                try { 
                    client.close();
                } catch (IOException e) { 
                    e.printStackTrace();
                }
            }
        }
    }

## 2.2 索引操作 ##

import com.codecoord.elasticsearch.utils.PrintUtil;
    import java.io.IOException;
    import java.util.Objects;
    import org.apache.http.HttpHost;
    import org.elasticsearch.action.admin.indices.delete.DeleteIndexRequest;
    import org.elasticsearch.action.support.master.AcknowledgedResponse;
    import org.elasticsearch.client.RequestOptions;
    import org.elasticsearch.client.RestClient;
    import org.elasticsearch.client.RestHighLevelClient;
    import org.elasticsearch.client.indices.CreateIndexRequest;
    import org.elasticsearch.client.indices.CreateIndexResponse;
    import org.elasticsearch.client.indices.GetIndexRequest;
    import org.elasticsearch.client.indices.GetIndexResponse;
    import org.junit.After;
    import org.junit.Before;
    import org.junit.Test;
    
    public class ElasticsearchIndexTest { 
        /** * 连接客户端 */
        private RestHighLevelClient client;
    
        @Before
        public void init() { 
            HttpHost serverHost = new HttpHost("127.0.0.1", 9200);
            client = new RestHighLevelClient(RestClient.builder(serverHost));
        }
    
        @After
        public void destroy() { 
            if (Objects.nonNull(client)) { 
                try { 
                    client.close();
                } catch (IOException e) { 
                    e.printStackTrace();
                }
            }
        }
    
        /** * 创建索引：有则报错，无则新建 */
        @Test
        public void testCreate() throws IOException { 
            CreateIndexRequest createIndexRequest = new CreateIndexRequest("java");
            CreateIndexResponse response = client.indices().create(createIndexRequest, RequestOptions.DEFAULT);
            PrintUtil.buttyPrint(response);
        }
    
        /** * 查询索引信息 */
        @Test
        public void testQuery() throws IOException { 
            GetIndexRequest request = new GetIndexRequest("java");
            GetIndexResponse response = client.indices().get(request, RequestOptions.DEFAULT);
            // 获取别名
            PrintUtil.buttyPrint(response.getAliases(), "getAliases");
            // 获取默认设置
            PrintUtil.buttyPrint(response.getDefaultSettings(), "getDefaultSettings");
            // 获取索引信息
            PrintUtil.buttyPrint(response.getIndices(), "getIndices");
            // 获取映射信息
            PrintUtil.buttyPrint(response.getMappings(), "getMappings");
        }
    
        /** * 删除索引 */
        @Test
        public void testDelete() throws IOException { 
            DeleteIndexRequest request = new DeleteIndexRequest("java");
            AcknowledgedResponse response = client.indices().delete(request, RequestOptions.DEFAULT);
            PrintUtil.buttyPrint(response);
        }
    }

## 2.3 文档操作 ##

*  以下文档操作为示例操作，关于高级查询只需要变化query即可

import com.codecoord.elasticsearch.domain.EsUser;
    import com.codecoord.elasticsearch.utils.PrintUtil;
    import java.io.IOException;
    import java.util.Objects;
    import org.apache.http.HttpHost;
    import org.elasticsearch.action.bulk.BulkRequest;
    import org.elasticsearch.action.bulk.BulkResponse;
    import org.elasticsearch.action.delete.DeleteRequest;
    import org.elasticsearch.action.delete.DeleteResponse;
    import org.elasticsearch.action.get.GetRequest;
    import org.elasticsearch.action.get.GetResponse;
    import org.elasticsearch.action.index.IndexRequest;
    import org.elasticsearch.action.index.IndexResponse;
    import org.elasticsearch.action.search.SearchRequest;
    import org.elasticsearch.action.search.SearchResponse;
    import org.elasticsearch.action.update.UpdateRequest;
    import org.elasticsearch.action.update.UpdateResponse;
    import org.elasticsearch.client.RequestOptions;
    import org.elasticsearch.client.RestClient;
    import org.elasticsearch.client.RestHighLevelClient;
    import org.elasticsearch.common.xcontent.XContentType;
    import org.elasticsearch.index.query.BoolQueryBuilder;
    import org.elasticsearch.index.query.MatchAllQueryBuilder;
    import org.elasticsearch.index.query.MatchQueryBuilder;
    import org.elasticsearch.index.query.QueryBuilder;
    import org.elasticsearch.index.query.QueryBuilders;
    import org.elasticsearch.search.SearchHit;
    import org.elasticsearch.search.builder.SearchSourceBuilder;
    import org.elasticsearch.search.fetch.subphase.highlight.HighlightBuilder;
    import org.elasticsearch.search.sort.SortOrder;
    import org.junit.After;
    import org.junit.Before;
    import org.junit.Test;
    
    public class ElasticsearchDocTest { 
        /** * 连接客户端 */
        private RestHighLevelClient client;
    
        @Before
        public void init() { 
            HttpHost serverHost = new HttpHost("127.0.0.1", 9200);
            client = new RestHighLevelClient(RestClient.builder(serverHost));
        }
    
        @After
        public void destroy() { 
            if (Objects.nonNull(client)) { 
                try { 
                    client.close();
                } catch (IOException e) { 
                    e.printStackTrace();
                }
            }
        }
    
        /** * 创建文档 */
        @Test
        public void testCreate() throws IOException { 
            IndexRequest request = new IndexRequest();
            // 指定索引
            request.index("java");
            // 指定id
            request.id("1001");
            // 存储数据
            EsUser user = new EsUser("zhangsan", 30, "男");
            // 指定source内容
            request.source(user.toJsonString(), XContentType.JSON);
            // 请求
            IndexResponse response = client.index(request, RequestOptions.DEFAULT);
            PrintUtil.buttyPrint(response);
        }
    
        /** * 修改文档 */
        @Test
        public void testUpdate() throws IOException { 
            UpdateRequest request = new UpdateRequest();
            // 指定索引
            request.index("java");
            // 指定id
            request.id("1001");
    
            // 更新内容
            EsUser user = new EsUser("ES", 18, "女");
            request.doc(user.toJsonString(), XContentType.JSON);
    
            // ES请求
            UpdateResponse response = client.update(request, RequestOptions.DEFAULT);
            PrintUtil.buttyPrint(response);
        }
    
        /** * 文档查询 */
        @Test
        public void testQuery() throws IOException { 
            GetRequest request = new GetRequest().index("java").id("1001");
            GetResponse response = client.get(request, RequestOptions.DEFAULT);
            PrintUtil.buttyPrint(response.getSource());
        }
    
        /** * 删除文档 */
        @Test
        public void testDelete() throws IOException { 
            DeleteRequest request = new DeleteRequest().index("java").id("1001");
            DeleteResponse response = client.delete(request, RequestOptions.DEFAULT);
            PrintUtil.buttyPrint(response);
        }
    
        /** * 批量操作，针对于增删改 */
        @Test
        public void testBatch() throws IOException { 
            BulkRequest bulkRequest = new BulkRequest();
            // 先删除
            bulkRequest.add(new DeleteRequest().index("java").id("1001"));
            // 再添加
            EsUser user = new EsUser("EsJava", 18, "男");
            bulkRequest.add(new IndexRequest().index("java").id("1002").source(user.toJsonString(), XContentType.JSON));
    
            BulkResponse responses = client.bulk(bulkRequest, RequestOptions.DEFAULT);
            PrintUtil.buttyPrint(responses);
        }
    
        /** * match查询 */
        @Test
        public void testAdvanceMatchQuery() throws IOException { 
            SearchRequest request = new SearchRequest("java");
    
            // 查询条件构造
            SearchSourceBuilder builder = new SearchSourceBuilder();
    
            // 匹配查询
            /// QueryBuilders提供命令中的查询匹配关系
            /// 查询所有
            /// QueryBuilder queryBuilder = QueryBuilders.matchAllQuery();
            /// 单个查询
            /// QueryBuilder queryBuilder = QueryBuilders.matchQuery("age", 18);
            /// 短语匹配查询
            QueryBuilder queryBuilder = QueryBuilders.matchPhraseQuery("name", "EsJava");
            builder.query(queryBuilder);
    
            request.source(builder);
            SearchResponse responses = client.search(request, RequestOptions.DEFAULT);
            PrintUtil.buttyPrint(responses.getHits());
        }
    
        /** * bool查询 */
        @Test
        public void testAdvanceBoolQuery() throws IOException { 
            SearchRequest request = new SearchRequest("java");
    
            // 查询条件构造
            SearchSourceBuilder builder = new SearchSourceBuilder();
            BoolQueryBuilder queryBuilder = QueryBuilders.boolQuery();
    
            // must
            queryBuilder.must(QueryBuilders.matchQuery("age", 18));
            // mustNot
            queryBuilder.mustNot(QueryBuilders.matchQuery("sex", "女"));
            // should
            queryBuilder.should(QueryBuilders.matchQuery("name", "zhangsan"));
    
            builder.query(queryBuilder);
            request.source(builder);
            SearchResponse responses = client.search(request, RequestOptions.DEFAULT);
            PrintUtil.buttyPrint(responses.getHits());
        }
    
        /** * 分页查询 */
        @Test
        public void testAdvancePageQuery() throws IOException { 
            SearchRequest request = new SearchRequest("java");
    
            // 查询条件构
            SearchSourceBuilder builder = new SearchSourceBuilder();
            MatchAllQueryBuilder queryBuilder = QueryBuilders.matchAllQuery();
    
            // query <==> select
            builder.query(queryBuilder);
    
            // 分页查询
            builder.from(0);
            builder.size(2);
    
            // 指定排序
            builder.sort("age", SortOrder.ASC);
    
            request.source(builder);
            SearchResponse responses = client.search(request, RequestOptions.DEFAULT);
            for (SearchHit searchHit : responses.getHits()) { 
                System.out.println(searchHit.getSourceAsString());
            }
        }
    
        /** * 高亮查询 */
        @Test
        public void testAdvanceHighLightQuery() throws IOException { 
            SearchRequest request = new SearchRequest("java");
    
            // 查询条件构
            SearchSourceBuilder builder = new SearchSourceBuilder();
            // 注意高亮全部查询时无意义
            MatchQueryBuilder queryBuilder = QueryBuilders.matchQuery("name", "java");
            builder.query(queryBuilder);
    
            // 高亮搜搜，和查询同级
            HighlightBuilder highlightBuilder = new HighlightBuilder();
            highlightBuilder.preTags("<font color='red'>");
            highlightBuilder.postTags("</font>");
            highlightBuilder.field("name");
    
            builder.highlighter(highlightBuilder);
            request.source(builder);
            SearchResponse responses = client.search(request, RequestOptions.DEFAULT);
            for (SearchHit searchHit : responses.getHits()) { 
                System.out.println(searchHit.getHighlightFields());
            }
        }
    }

[https_www.elastic.co_guide_en_elasticsearch_client_java-rest_7.x_java-rest-high-create-index.html]: https://www.elastic.co/guide/en/elasticsearch/client/java-rest/7.x/java-rest-high-create-index.html