ElasticSearch中基础API操作

1:首先我们需要连接ElasticSearch客户端，需要一个连接操作： RestHighLevelClient

package com.atguigu.es.test;

import org.apache.http.HttpHost;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;

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();
    }
}

2:建立的客户端后，我们需要先进行索引的创建，查询，删除操作：

2.1：创建索引： CreateIndexRequest 响应： esClient.indices().create

package com.atguigu.es.test;

import org.apache.http.HttpHost;
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;

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();
    }
}

2.2：查询索引： GetIndexRequest 响应： esClient.indices().get

package com.atguigu.es.test;

import org.apache.http.HttpHost;
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;

public class ESTest_Index_Search {
    public static void main(String[] args) throws Exception {

        RestHighLevelClient esClient = new RestHighLevelClient(
                RestClient.builder(new HttpHost("localhost", 9200, "http"))
        );

        // 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());

        esClient.close();
    }
}

2.3：删除索引： DeleteIndexRequest 响应： esClient.indices().delete

package com.atguigu.es.test;

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.GetIndexRequest;
import org.elasticsearch.client.indices.GetIndexResponse;

public class ESTest_Index_Delete {
    public static void main(String[] args) throws Exception {

        RestHighLevelClient esClient = new RestHighLevelClient(
                RestClient.builder(new HttpHost("localhost", 9200, "http"))
        );

        // 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());

        esClient.close();
    }
}

3：索引创建好后我们需要将索引里面插入文档数据，包过数据的查询删除等等操作

3.1：将数据插入索引： IndexRequest 响应：esClient.index

3.1.1：首先建立一个实体类存放我们要插入的数据类：User

#3.1.2：然后向对应的索引中插入数据：这里的步骤分三步：

（1）：new出索引，并指向我们要插入数据的索引： request.index("user").id("1001");

（2）：将数据插入到实体类，并要穿换成json格式：

（3）：默认响应：IndexResponse：esClient.index

   IndexResponse response = esClient.index(request, RequestOptions.DEFAULT);

package com.atguigu.es.test;

import com.fasterxml.jackson.databind.ObjectMapper;
import org.apache.http.HttpHost;
import org.elasticsearch.action.index.IndexRequest;
import org.elasticsearch.action.index.IndexResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.client.indices.GetIndexRequest;
import org.elasticsearch.client.indices.GetIndexResponse;
import org.elasticsearch.common.xcontent.XContentType;

public class ESTest_Doc_Insert {
    public static void main(String[] args) throws Exception {

        RestHighLevelClient esClient = new RestHighLevelClient(
                RestClient.builder(new HttpHost("localhost", 9200, "http"))
        );

        // 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());

        esClient.close();
    }
}

3.2：修改索引中数据：UpdateRequest 响应： esClient.update

修改索引中的数据：跟上面类似，还是要先定位到哪个索引然后进行修改：

package com.atguigu.es.test;

import com.fasterxml.jackson.databind.ObjectMapper;
import org.apache.http.HttpHost;
import org.elasticsearch.action.index.IndexRequest;
import org.elasticsearch.action.index.IndexResponse;
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;

public class ESTest_Doc_Update {
    public static void main(String[] args) throws Exception {

        RestHighLevelClient esClient = new RestHighLevelClient(
                RestClient.builder(new HttpHost("localhost", 9200, "http"))
        );

        // 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());

        esClient.close();
    }
}

3.3：查询索引中的数据： GetRequest 响应： esClient.get

package com.atguigu.es.test;

import org.apache.http.HttpHost;
import org.elasticsearch.action.get.GetRequest;
import org.elasticsearch.action.get.GetResponse;
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;

public class ESTest_Doc_Get {
    public static void main(String[] args) throws Exception {

        RestHighLevelClient esClient = new RestHighLevelClient(
                RestClient.builder(new HttpHost("localhost", 9200, "http"))
        );

        // 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());

        esClient.close();
    }
}

3.4：删除索引中的文档（数据）： DeleteRequest 响应：esClient.delete

package com.atguigu.es.test;

import org.apache.http.HttpHost;
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.client.RequestOptions;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;

public class ESTest_Doc_Delete {
    public static void main(String[] args) throws Exception {

        RestHighLevelClient esClient = new RestHighLevelClient(
                RestClient.builder(new HttpHost("localhost", 9200, "http"))
        );


        DeleteRequest request = new DeleteRequest();
        request.index("user").id("1001");

        DeleteResponse response = esClient.delete(request, RequestOptions.DEFAULT);
        System.out.println(response.toString());

        esClient.close();
    }
}

3.5：批量插入数据： BulkRequest 响应： esClient.bulk

相当于就是在一个BulkRequest里面包含很多IndexRequest().index

package com.atguigu.es.test;

import com.fasterxml.jackson.databind.ObjectMapper;
import org.apache.http.HttpHost;
import org.elasticsearch.action.bulk.BulkRequest;
import org.elasticsearch.action.bulk.BulkResponse;
import org.elasticsearch.action.index.IndexRequest;
import org.elasticsearch.action.index.IndexResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.common.xcontent.XContentType;

public class ESTest_Doc_Insert_Batch {
    public static void main(String[] args) throws Exception {

        RestHighLevelClient esClient = new RestHighLevelClient(
                RestClient.builder(new HttpHost("localhost", 9200, "http"))
        );

        // 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"));
//        request.add(new IndexRequest().index("user").id("1004").source(XContentType.JSON, "name", "wangwu1", "age",40,"sex","女"));
//        request.add(new IndexRequest().index("user").id("1005").source(XContentType.JSON, "name", "wangwu2", "age",50,"sex","男"));
//        request.add(new IndexRequest().index("user").id("1006").source(XContentType.JSON, "name", "wangwu3", "age",50,"sex","男"));
        //request.add(new IndexRequest().index("user").id("1007").source(XContentType.JSON, "name", "wangwu44", "age",60,"sex","男"));
        //request.add(new IndexRequest().index("user").id("1008").source(XContentType.JSON, "name", "wangwu555", "age",60,"sex","男"));
        request.add(new IndexRequest().index("user").id("1009").source(XContentType.JSON, "name", "wangwu66666", "age",60,"sex","男"));

        BulkResponse response = esClient.bulk(request, RequestOptions.DEFAULT);
        System.out.println(response.getTook());
        System.out.println(response.getItems());

        esClient.close();
    }
}

3.6：批量删除： BulkRequest 响应：esClient.bulk，相当于一个 BulkRequest里面包含很多DeleteRequest().index

package com.atguigu.es.test;

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.index.IndexRequest;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.common.xcontent.XContentType;

public class ESTest_Doc_Delete_Batch {
    public static void main(String[] args) throws Exception {

        RestHighLevelClient esClient = new RestHighLevelClient(
                RestClient.builder(new HttpHost("localhost", 9200, "http"))
        );

        // 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());

        esClient.close();
    }
}

3.7：全量查询：SearchRequest 响应：esClient.search

注意变化： request.indices("user");

   RestHighLevelClient esClient = new RestHighLevelClient(
                RestClient.builder(new HttpHost("localhost", 9200, "http"))
        );

        // 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());
        }

3.8：条件查询：与全量查询变化：QueryBuilders.termQuery("age", 30)

        // 2. 条件查询 : termQuery
        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());
        }

3.9：分页查询 builder.from(2); builder.size(2);

    3. 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());
        }

3.10：查询排序： builder.sort("age", SortOrder.DESC);

        // 4. 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());
        }

3.11：过滤字段 builder.fetchSource(includes, excludes);

        // 5. 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());
        }

3.12：组合查询 ：

     // 6. 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());
        }

3.13：范围查询 ： QueryBuilders.rangeQuery("age");

        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());
        }

3.14：模糊查询：QueryBuilders.fuzzyQuery("name","wangwu").fuzziness(Fuzziness.TWO)

Fuzziness.TWO：意思就是字符差两个就可以查出来，代表模糊的范围

        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());
        }

3.15：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());
        }

3.16：聚合查询：（求最大最小）对age字段取最大：maxAge

        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());
        }

3.17：分组查询 terms(“ageGroup”).field(“age”);： 根据年龄分组

        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());
        }