Elasticsearch 之Java操作
废话不多说，最终所有的操作都得落实到业务代码上来，就像我们学了那么多sql，最后还是得使用Java来进行数据库操作，对此ES也一样
简单的来说，也是crud操作
这里导入依赖
这里es版本 7.x
boot版本 2.0.1.RELEASE
依赖
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
</dependency>
<dependency>
<groupId>org.elasticsearch.client</groupId>
<artifactId>elasticsearch-rest-high-level-client</artifactId>
<version>7.3.0</version>
<exclusions>
<exclusion>
<groupId>org.elasticsearch</groupId>
<artifactId>elasticsearch</artifactId>
</exclusion>
</exclusions>
</dependency>
<dependency>
<groupId>org.elasticsearch</groupId>
<artifactId>elasticsearch</artifactId>
<version>7.3.0</version>
</dependency>
</dependencies>
配置地址
lagouelasticsearch.elasticsearch.hostlist=127.0.0.1:9200
操后就是业务代码CRUD操作
配置
package com.example.esdemo.config;
import org.apache.http.HttpHost;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
@Configuration
public class ElasticsearchConfig {
@Value("${lagouelasticsearch.elasticsearch.hostlist}")
private String hostlist;
@Bean
public RestHighLevelClient restHighLevelClient() {
//解析hostlist配置信息
String[] split = hostlist.split(",");
//创建HttpHost数组，其中存放es主机和端口的配置信息
HttpHost[] httpHostArray = new HttpHost[split.length];
for (int i = 0; i < split.length; i++) {
String item = split[i];
httpHostArray[i] = new HttpHost(item.split(":")[0], Integer.parseInt(item.split(":")[1]), "http");
}
//创建RestHighLevelClient客户端
return new RestHighLevelClient(RestClient.builder(httpHostArray));
}//项目主要使用RestHighLevelClient，对于低级的客户端暂时不用
@Bean
public RestClient restClient() {
// 解析hostlist配置信息
String[] split = hostlist.split(",");
//创建HttpHost数组，其中存放es主机和端口的配置信息
HttpHost[] httpHostArray = new HttpHost[split.length];
for (int i = 0; i < split.length; i++) {
String item = split[i];
httpHostArray[i] = new HttpHost(item.split(":")[0], Integer.parseInt(item.split(":")[1]), "http");
}
return RestClient.builder(httpHostArray).build();
}
}
CRUD操作API了
啥也不多说了，很简单。
创建索引，新增数据，查询数据等操作。
看一下代码就能明白。
package com.example.esdemo;
import org.apache.lucene.search.TotalHits;
import org.elasticsearch.action.DocWriteResponse;
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.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.client.IndicesClient;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.common.settings.Settings;
import org.elasticsearch.common.xcontent.XContentType;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.SearchHits;
import org.elasticsearch.search.builder.SearchSourceBuilder;
import org.elasticsearch.search.sort.SortBuilder;
import org.elasticsearch.search.sort.SortOrder;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;
import java.io.IOException;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.HashMap;
import java.util.Map;
@SpringBootTest
@RunWith(SpringRunner.class)
public class EsDemoApplicationTests {
//
// @Test
// void contextLoads() {
// }
@Autowired
RestHighLevelClient client;
@Autowired
RestClient restClient;
/**
* 1 创建索引库
*/
/*PUT
/elasticsearch_test
{ "settings": {}, "mappings": { "properties": { "description": { "type": "text", "analyzer": "ik_max_word" },"name": { "type": "keyword" },"pic": { "type": "text", "index": false },"studymodel": { "type": "keyword" } } } }
*/
@Test
public void testCreateIndex() throws IOException {
//创建索引对象
CreateIndexRequest createIndexRequest = new CreateIndexRequest("elasticsearch_test");
//设置参数
createIndexRequest.settings(Settings.builder().put("number_of_shards", "1").put("number_of_replicas", "0"));
//todo 第一种创建方法 拼接字符串
// 指定映射
// XContentBuilder builder = XContentFactory.jsonBuilder()
// .startObject().field("properties")
// .startObject().field("studymodel")
// .startObject().field("index", "true").field("type", "keyword")
// .endObject().field("name")
// .startObject().field("index", "true").field("type", "integer")
// .endObject().field("description")
// .startObject().field("index", "true").field("type", "text").field("analyzer", "ik_max_word")
// .endObject().field("pic").startObject().field("index", "false").field("type", "text")
// .endObject()
// .endObject()
// .endObject();
// createIndexRequest.mapping("doc", builder);
//todo 第二种创建方法 dsl json 字符串转换对象
//指定映射
createIndexRequest.mapping("doc",
" {\n" + " \t\"properties\": {\n" + " \"studymodel\":{\n" + " \"type\":\"keyword\"\n" + " },\n"
+ " \"name\":{\n" + " \"type\":\"keyword\"\n" + " },\n"
+ " \"description\": {\n" + " \"type\": \"text\",\n" + " \"analyzer\":\"ik_max_word\" \n" + " },\n"
+ " \"pic\":{\n" + " \"type\":\"text\",\n" + " \"index\":false\n" + " }\n" + " \t}\n" + "}",
XContentType.JSON);
//操作索引的客户端
IndicesClient indices = client.indices();
//执行创建索引库
//CreateIndexResponse createIndexResponse = indices.create(createIndexRequest, RequestOptions.DEFAULT);
CreateIndexResponse createIndexResponse = indices.create(createIndexRequest, RequestOptions.DEFAULT);
//得到响应
boolean acknowledged = createIndexResponse.isAcknowledged();
System.out.println(acknowledged);
}
//删除索引库
@Test
public void testDeleteIndex() throws IOException {
//删除索引的请求对象
DeleteIndexRequest deleteIndexRequest = new DeleteIndexRequest("elasticsearch_test");
//操作索引的客户端
IndicesClient indices = client.indices();
//执行删除索引
AcknowledgedResponse delete = indices.delete(deleteIndexRequest, RequestOptions.DEFAULT);
//得到响应
boolean acknowledged = delete.isAcknowledged();
System.out.println(acknowledged);
}
//添加文档
/*
POST /elasticsearch_test/_doc/1 { "name": "spring cloud实战",
"description": "本课程主要从四个章节进行讲解： 1.微服务架构入门 2.spring cloud 基 础入门 3.实战Spring Boot 4.注册中心eureka。",
"studymodel":"201001",
"timestamp": "2020-08-22 20:09:18",
"price": 5.6
}
*/
@Test
public void testAddDoc() throws IOException {
//创建索引请求对象
IndexRequest indexRequest = new IndexRequest("elasticsearch_test", "doc");
indexRequest.id("4");
//文档内容 准备json数据
Map<String, Object> jsonMap = new HashMap<>();
jsonMap.put("name", "spring cloud实战");
jsonMap.put("description", "本课程主要从四个章节进行讲解： 1.微服务架构入门 2.spring cloud 基础入门 3.实战Spring Boot 4.注册中心eureka。");
jsonMap.put("studymodel", "201001");
SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
jsonMap.put("timestamp", dateFormat.format(new Date()));
jsonMap.put("price", 5.6F);
indexRequest.source(jsonMap);
//通过client进行http的请求
IndexResponse indexResponse = client.index(indexRequest, RequestOptions.DEFAULT);
DocWriteResponse.Result result = indexResponse.getResult();
System.out.println(result);
}
//查询文档
//
@Test
public void testGetDoc() throws IOException {
//查询请求对象
GetRequest getRequest = new GetRequest("elasticsearch_test", "2");
GetResponse getResponse = client.get(getRequest, RequestOptions.DEFAULT);
//得到文档的内容
Map<String, Object> sourceAsMap = getResponse.getSourceAsMap();
System.out.println(sourceAsMap);
}
//搜索全部记录
/* GET /elasticsearch_test/_search { "query":{ "match_all":{} } } */
@Test
public void testSearchAll() throws IOException, ParseException, ParseException {
//搜索请求对象
SearchRequest searchRequest = new SearchRequest("elasticsearch_test");
//搜索源构建对象
SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();
//搜索方式
// matchAllQuery搜索全部
searchSourceBuilder.query(QueryBuilders.matchAllQuery());
//设置源字段过虑,第一个参数结果集包括哪些字段，第二个参数表示结果集不包括哪些字段
searchSourceBuilder.fetchSource(new String[]{"name", "studymodel", "price", "timestamp"}, new String[]{});
//向搜索请求对象中设置搜索源
searchRequest.source(searchSourceBuilder);
//执行搜索,向ES发起http请求
SearchResponse searchResponse = client.search(searchRequest, RequestOptions.DEFAULT);
//搜索结果
SearchHits hits = searchResponse.getHits();
//匹配到的总记录数
TotalHits totalHits = hits.getTotalHits();
System.out.println(" 总记录 : " + totalHits);
//得到匹配度高的文档
SearchHit[] searchHits = hits.getHits();
//日期格式化对象
SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
for (SearchHit hit : searchHits) {
//文档的主键
String id = hit.getId();
//源文档内容
Map<String, Object> sourceAsMap = hit.getSourceAsMap();
String name = (String) sourceAsMap.get("name");
//由于前边设置了源文档字段过虑，这时description是取不到的
String description = (String) sourceAsMap.get("description");
//学习模式
String studymodel = (String) sourceAsMap.get("studymodel");
// 价格
Double price = (Double) sourceAsMap.get("price");
// 日期
Date timestamp = dateFormat.parse((String) sourceAsMap.get("timestamp"));
System.out.println(name);
System.out.println(studymodel);
System.out.println(description);
System.out.println(timestamp);
System.out.println(price);
}
}
//TermQuery
@Test
public void testTermQuery1() throws IOException, ParseException {
//搜索请求对象
SearchRequest searchRequest = new SearchRequest("elasticsearch_test");
//搜索源构建对象
SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();
//搜索方式
// termQuery name字段查询需要分词 // 默认是 "type" : "keyword"
//searchSourceBuilder.query(QueryBuilders.termQuery("name", "spring"));
searchSourceBuilder.query(QueryBuilders.termQuery("description", "spring"));
//设置源字段过虑,第一个参数结果集包括哪些字段，第二个参数表示结果集不包括哪些字段
searchSourceBuilder.fetchSource(new String[]{"name", "studymodel", "price", "timestamp"}, new String[]{});
//向搜索请求对象中设置搜索源
searchRequest.source(searchSourceBuilder);
//执行搜索,向ES发起http请求
SearchResponse searchResponse = client.search(searchRequest, RequestOptions.DEFAULT);
//搜索结果
SearchHits hits = searchResponse.getHits();
//匹配到的总记录数
TotalHits totalHits = hits.getTotalHits();
//得到匹配度高的文档
SearchHit[] searchHits = hits.getHits();
//日期格式化对象
SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
for (SearchHit hit : searchHits) {
//文档的主键
String id = hit.getId();
//源文档内容
Map<String, Object> sourceAsMap = hit.getSourceAsMap();
String name = (String) sourceAsMap.get("name");
//由于前边设置了源文档字段过虑，这时description是取不到的
String description = (String) sourceAsMap.get("description");
//学习模式
String studymodel = (String) sourceAsMap.get("studymodel");
//价格
Double price = (Double) sourceAsMap.get("price");
//日期
Date timestamp = dateFormat.parse((String) sourceAsMap.get("timestamp"));
System.out.println(name);
System.out.println(studymodel);
System.out.println(description);
}
}
//分页查询
@Test
public void testSearchPage() throws IOException, ParseException {
//搜索请求对象
SearchRequest searchRequest = new SearchRequest("elasticsearch_test");
// 指定类型
searchRequest.types("doc");
// 搜索源构建对象
SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();
// 设置分页参数
// 页码
int page = 1;
// 每页记录数
int size = 2;
// 计算出记录起始下标
int from = (page - 1) * size;
searchSourceBuilder.from(from);
// 起始记录下标，从0开始
searchSourceBuilder.size(size);
//每页显示的记录数
// 搜索方式
//matchAllQuery搜索全部
searchSourceBuilder.query(QueryBuilders.matchAllQuery());
//设置源字段过虑,第一个参数结果集包括哪些字段，第二个参数表示结果集不包括哪些字段
searchSourceBuilder.fetchSource(new String[]{"name", "studymodel", "price", "timestamp"}, new String[]{});
//设置排序
searchSourceBuilder.sort("_id", SortOrder.DESC);
//向搜索请求对象中设置搜索源
searchRequest.source(searchSourceBuilder);
// 执行搜索,向ES发起http请求
SearchResponse searchResponse = client.search(searchRequest, RequestOptions.DEFAULT);
// 搜索结果
SearchHits hits = searchResponse.getHits();
// 匹配到的总记录数
TotalHits totalHits = hits.getTotalHits();
System.out.println(" 总记录数: " + totalHits);
// 得到匹配度高的文档
SearchHit[] searchHits = hits.getHits();
// 日期格式化对象
SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
for (SearchHit hit : searchHits) {
// 文档的主键
String id = hit.getId();
// 源文档内容
Map<String, Object> sourceAsMap = hit.getSourceAsMap();
String name = (String) sourceAsMap.get("name");
// 由于前边设置了源文档字段过虑，这时description是取不到的
String description = (String) sourceAsMap.get("description");
// 学习模式
String studymodel = (String) sourceAsMap.get("studymodel");
// 价格
Double price = (Double) sourceAsMap.get("price");
// 日期
Date timestamp = dateFormat.parse((String) sourceAsMap.get("timestamp"));
System.out.println(id);
System.out.println(name);
System.out.println(timestamp);
System.out.println(studymodel);
System.out.println(description);
}
}
@Test
public void testTermQuery() throws IOException, ParseException {
//搜索请求对象
SearchRequest searchRequest = new SearchRequest("elasticsearch_test");
//搜索源构建对象
SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();
//设置分页参数
// 页码
int page = 1;//每页记录数
int size = 2;//计算出记录起始下标
int from = (page - 1) * size;
searchSourceBuilder.from(from);//起始记录下标，从0开始
searchSourceBuilder.size(size); //每页显示的记录数
// 搜索方式
//termQuery
searchSourceBuilder.query(QueryBuilders.termQuery("name", "spring"));
//设置源字段过虑,第一个参数结果集包括哪些字段，第二个参数表示结果集不包括哪些字段
searchSourceBuilder.fetchSource(new String[]{"name", "studymodel", "price", "timestamp"}, new String[]{});
//向搜索请求对象中设置搜索源
searchRequest.source(searchSourceBuilder);
//执行搜索,向ES发起http请求
SearchResponse searchResponse = client.search(searchRequest, RequestOptions.DEFAULT);
//搜索结果
SearchHits hits = searchResponse.getHits();
//匹配到的总记录数
TotalHits totalHits = hits.getTotalHits();
//得到匹配度高的文档
SearchHit[] searchHits = hits.getHits();
//日期格式化对象
SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
for (SearchHit hit : searchHits) {
//文档的主键
String id = hit.getId();
//源文档内容
Map<String, Object> sourceAsMap = hit.getSourceAsMap();
String name = (String) sourceAsMap.get("name");
//由于前边设置了源文档字段过虑，这时description是取不到的
String description = (String) sourceAsMap.get("description");
//学习模式
String studymodel = (String) sourceAsMap.get("studymodel");
//价格
Double price = (Double) sourceAsMap.get("price");
//日期
Date timestamp = dateFormat.parse((String) sourceAsMap.get("timestamp"));
System.out.println(name);
System.out.println(studymodel);
System.out.println(description);
}
}
}
