ElasticSearch入门（五）SpringBoot2.3.0集成ElasticSearch7.5.2-HighLevelClient
背景
今天来实现SpringBoot集成ElasticSearch，ElasticSearch官方提供了两种Java REST Client。推荐使用HighLevelClient的方式，HighLevelClient本身是基于Low Level REST Client封装而来。
The Java REST Client comes in 2 flavors:
Java Low Level REST Client: the official low-level client for Elasticsearch. It allows to communicate with an Elasticsearch cluster through http. Leaves requests marshalling and responses un-marshalling to users. It is compatible with all Elasticsearch versions.
Java High Level REST Client: the official high-level client for Elasticsearch. Based on the low-level client, it exposes API specific methods and takes care of requests marshalling and responses un-marshalling.
核心依赖
<dependency>
<groupId>org.elasticsearch.clientgroupId>
<artifactId>elasticsearch-rest-high-level-clientartifactId>
<version>7.5.2version>
dependency>
<dependency>
<groupId>org.elasticsearch.clientgroupId>
<artifactId>elasticsearch-rest-clientartifactId>
<version>7.5.2version>
dependency>
<dependency>
<groupId>org.elasticsearchgroupId>
<artifactId>elasticsearchartifactId>
<version>7.5.2version>
dependency>
核心方法
package com.heartsuit.service;
import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;
import lombok.extern.slf4j.Slf4j;
import org.elasticsearch.action.admin.indices.create.CreateIndexRequest;
import org.elasticsearch.action.admin.indices.create.CreateIndexResponse;
import org.elasticsearch.action.admin.indices.delete.DeleteIndexRequest;
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.support.master.AcknowledgedResponse;
import org.elasticsearch.action.update.UpdateRequest;
import org.elasticsearch.action.update.UpdateResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.client.indices.GetIndexRequest;
import org.elasticsearch.common.xcontent.XContentType;
import org.elasticsearch.index.query.MatchAllQueryBuilder;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.builder.SearchSourceBuilder;
import org.springframework.stereotype.Component;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
/**
* @Author Heartsuit
* @Date 2020-06-04
*/
@Slf4j
@Component
public class ElasticSearchServiceImpl implements ElasticSearchService {
private final RestHighLevelClient client;
public ElasticSearchServiceImpl(RestHighLevelClient client) {
this.client = client;
}
/**
* 创建索引
*
* @param index 必须小写,格式参考文档，否则报错：Elasticsearch exception [type=invalid_index_name_exception, reason=Invalid index name [OK], must be lowercase]
* @return 是否创建成功
*/
@Override
public boolean createIndex(String index) {
CreateIndexResponse response;
try {
if (!this.existsIndex(index)) {
response = client.indices().create(new CreateIndexRequest(index), RequestOptions.DEFAULT);
} else {
return true;//索引已存在
}
} catch (Exception e) {
log.error("ElasticSearch 创建索引异常：{}", e.getMessage());
return false;
}
return response.isAcknowledged();
}
/**
* 判断索引是否存在
*
* @param index
* @return
*/
private boolean existsIndex(String index) throws IOException {
return client.indices().exists(new GetIndexRequest(index), RequestOptions.DEFAULT);
}
/**
* 删除索引
*
* @param index 必须小写,格式参考文档，否则：找不到大写索引名
* @return 是否删除成功
*/
@Override
public boolean deleteIndex(String index) {
AcknowledgedResponse response = null;
try {
if (this.existsIndex(index)) {
response = client.indices().delete(new DeleteIndexRequest(index), RequestOptions.DEFAULT);
} else {
return true;//索引不存在
}
} catch (Exception e) {
log.error("ElasticSearch 删除索引异常：{}", e.getMessage());
return false;
}
return response.isAcknowledged();
}
/**
* 创建文档
* id相同则更新、不同则创建,数据格式（字段）不同则空,字段为追加模式
*
* @param index 索引
* @param data 数据
* @param dataType 格式类型 例:XContentType.JSON
* @param id 唯一标识 put /index/1
* @return
*/
@Override
public int insertDocument(String index, Object data, XContentType dataType, String id) {
IndexRequest request = new IndexRequest(index);
request.id(id);
String dataString = JSONObject.toJSONString(data);
request.source(dataString, dataType);
IndexResponse response = null;
try {
response = client.index(request, RequestOptions.DEFAULT);
} catch (Exception e) {
log.error("ElasticSearch 创建文档异常：{}", e.getMessage());
}
return response != null ? response.status().getStatus() : 400;
}
/**
* 获取文档
*
* @param index
* @param id
* @param mappingClass
* @param
* @return
*/
@Override
public <T> T getDocument(String index, String id, Class<T> mappingClass) {
GetResponse getResponse = null;
try {
if (this.existsIndex(index)) {
GetRequest getRequest = new GetRequest(index, id);
getResponse = client.get(getRequest, RequestOptions.DEFAULT);
String sourceAsString = getResponse.getSourceAsString();
if (sourceAsString == null || sourceAsString.isEmpty()) {
return null;
}
/**Jackson日期时间序列化问题：
* Cannot construct instance of `java.time.LocalDateTime` (no Creators, like default constructor, exist): no String-argument constructor/factory method to deserialize from String value ('2020-06-04 15:07:54')
*/
// ObjectMapper objectMapper = new ObjectMapper();
// objectMapper.disable(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS);
// objectMapper.registerModule(new JavaTimeModule());
// T result = objectMapper.readValue(sourceAsString, mappingClass);
T result = JSON.parseObject(sourceAsString, mappingClass);
return result;
}
} catch (Exception e) {
log.error("ElasticSearch 获取文档异常：{}", e.getMessage());
}
return null;
}
/**
* 更新文档信息
*
* @param index
* @param data
* @param dataType
* @param id
* @return
*/
@Override
public int updateDocument(String index, Object data, XContentType dataType, String id) {
UpdateResponse updateResponse = null;
try {
if (this.existsIndex(index)) {
UpdateRequest updateRequest = new UpdateRequest(index, id);
String dataString = JSONObject.toJSONString(data);
updateRequest.doc(dataString, dataType);
updateResponse = client.update(updateRequest, RequestOptions.DEFAULT);
}
} catch (Exception e) {
log.error("ElasticSearch 更新文档异常：{}", e.getMessage());
}
return updateResponse != null ? updateResponse.status().getStatus() : 400;
}
/**
* 删除文档
*
* @param index
* @param id
* @return
*/
@Override
public int deleteDocument(String index, String id) {
DeleteResponse deleteResponse = null;
try {
if (this.existsIndex(index)) {
DeleteRequest deleteRequest = new DeleteRequest(index, id);
deleteResponse = client.delete(deleteRequest, RequestOptions.DEFAULT);
}
} catch (Exception e) {
log.error("ElasticSearch 删除文档异常：{}", e.getMessage());
}
return deleteResponse != null ? deleteResponse.status().getStatus() : 400;
}
/**
* 批量操作文档信息
* 备注:暂局限入参list,可扩展其他
*
* @param index
* @param list 标识相同则覆盖,否则新增
* @param dataType
* @return
*/
@Override
public boolean batchInsertDocument(String index, List<?> list, XContentType dataType) {
BulkRequest bulkRequest = new BulkRequest();
for (Object obj : list) {
// 自动生成id
bulkRequest.add(new IndexRequest(index).source(JSON.toJSONString(obj), dataType));
}
BulkResponse bulk = null;
try {
bulk = client.bulk(bulkRequest, RequestOptions.DEFAULT);
} catch (Exception e) {
log.error("ElasticSearch批量操作文档信息异常：{}", e.getMessage());
}
return bulk != null && !bulk.hasFailures();
}
/**
* 查询数据
* 备注：可拓展深入精准查询、范围查询、模糊查询、匹配所有等
*
* @param index
* @return
*/
@Override
public List<Map<String, Object>> searchDocument(String index) {
SearchRequest searchRequest = new SearchRequest(index);
SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();
MatchAllQueryBuilder termQueryBuilder = QueryBuilders.matchAllQuery();
sourceBuilder.query(termQueryBuilder);
// sourceBuilder.timeout(new TimeValue(60, TimeUnit.SECONDS));
searchRequest.source(sourceBuilder);
SearchResponse search;
try {
search = client.search(searchRequest, RequestOptions.DEFAULT);
} catch (Exception e) {
log.error("ElasticSearch 查询数据异常：{}", e.getMessage());
return null;
}
SearchHit[] hits = search.getHits().getHits();
List<Map<String, Object>> mapList = new ArrayList<>();
for (SearchHit hit : hits) {
mapList.add(hit.getSourceAsMap());
}
return mapList;
}
private void close(RestHighLevelClient client) {
try {
client.close();
} catch (IOException e) {
log.error("ElasticSearch 关闭异常：{}", e.getMessage());
}
}
}
Note: 使用FastJson替换了SpringBoot的默认Json解析器Jackson，参考
Source Code
Github
References
- https://www.elastic.co/guide/en/elasticsearch/client/java-rest/7.5/java-rest-high.html
Done~，下一篇采用另一种方式完成集成，即利用SpringDataElasticsearch实现SpringBoot集成ElasticSearch。
If you have any questions or any bugs are found, please feel free to contact me.
Your comments and suggestions are welcome!