SpringBoot集成ElasticSearch,实现模糊查询,批量CRUD,排序,分页,高亮

timo-nbktp 1年前 ⋅ 537 阅读

一、导入elasticsearch依赖

在pom.xml里加入如下依赖

<dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-data-elasticsearch</artifactId>
</dependency>

非常重要:检查依赖版本是否与你当前所用的版本是否一致,如果不一致,会连接失败!!!!!!!!

二、创建高级客户端

import org.apache.http.HttpHost;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

@Configuration
public class ElasticSearchClientConfig {
    @Bean
    public RestHighLevelClient restHighLevelClient(){
        RestHighLevelClient client = new RestHighLevelClient(
                RestClient.builder(
                        new HttpHost("服务器IP", 9200, "http")));
        return client;
    }
}

三、基本用法

1.创建、判断存在、删除索引

import org.elasticsearch.action.admin.indices.delete.DeleteIndexRequest;
import org.elasticsearch.action.support.master.AcknowledgedResponse;
import org.elasticsearch.client.RequestOptions;
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.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;

import java.io.IOException;

@SpringBootTest
class ElasticsearchApplicationTests {

	@Autowired
	private RestHighLevelClient restHighLevelClient;

	@Test
	void testCreateIndex() throws IOException {
		//1.创建索引请求
		CreateIndexRequest request = new CreateIndexRequest("ljx666");
		//2.客户端执行请求IndicesClient,执行create方法创建索引,请求后获得响应
		CreateIndexResponse response=
				restHighLevelClient.indices().create(request, RequestOptions.DEFAULT);
		System.out.println(response);
	}

	@Test
	void testExistIndex() throws IOException {
        //1.查询索引请求
		GetIndexRequest request=new GetIndexRequest("ljx666");
        //2.执行exists方法判断是否存在
		boolean exists=restHighLevelClient.indices().exists(request,RequestOptions.DEFAULT);
		System.out.println(exists);
	}

	@Test
	void testDeleteIndex() throws IOException {
        //1.删除索引请求
		DeleteIndexRequest request=new DeleteIndexRequest("ljx666");
        //执行delete方法删除指定索引
		AcknowledgedResponse delete = restHighLevelClient.indices().delete(request, RequestOptions.DEFAULT);
		System.out.println(delete.isAcknowledged());
	}

}

2.对文档的CRUD

创建文档:
        注意:如果添加时不指定文档ID,他就会随机生成一个ID,ID唯一。
创建文档时若该ID已存在,发送创建文档请求后会更新文档中的数据。

@Test
void testAddUser() throws IOException {
	//1.创建对象
	User user=new User("Go",21,new String[]{"内卷","吃饭"});
	//2.创建请求
	IndexRequest request=new IndexRequest("ljx666");
	//3.设置规则 PUT /ljx666/_doc/1
	//设置文档id=6,设置超时=1s等,不设置会使用默认的
	//同时支持链式编程如 request.id("6").timeout("1s");
	request.id("6");
	request.timeout("1s");

	//4.将数据放入请求,要将对象转化为json格式
    //XContentType.JSON,告诉它传的数据是JSON类型
	request.source(JSONValue.toJSONString(user), XContentType.JSON);
    
	//5.客户端发送请求,获取响应结果
	IndexResponse indexResponse=restHighLevelClient.index(request,RequestOptions.DEFAULT);
	System.out.println(indexResponse.toString());
	System.out.println(indexResponse.status());
}

获取文档中的数据:

@Test
void testGetUser() throws IOException {
	//1.创建请求,指定索引、文档id
	GetRequest request=new GetRequest("ljx666","1");
	GetResponse getResponse=restHighLevelClient.get(request,RequestOptions.DEFAULT);
		
	System.out.println(getResponse);//获取响应结果
	//getResponse.getSource() 返回的是Map集合
	System.out.println(getResponse.getSourceAsString());//获取响应结果source中内容,转化为字符串
		
}

更新文档数据:
        注意:需要将User对象中的属性全部指定值,不然会被设置为空,如User只设置了名称,那么只有名称会被修改成功,其他会被修改为null。

@Test
void testUpdateUser() throws IOException {
	//1.创建请求,指定索引、文档id
	UpdateRequest request=new UpdateRequest("ljx666","6");

	User user =new User("GoGo",21,new String[]{"内卷","吃饭"});
	//将创建的对象放入文档中
	request.doc(JSONValue.toJSONString(user),XContentType.JSON);

	UpdateResponse updateResponse=restHighLevelClient.update(request,RequestOptions.DEFAULT);
	System.out.println(updateResponse.status());//更新成功返回OK
}

删除文档:

@Test
void testDeleteUser() throws IOException {
	//创建删除请求,指定要删除的索引与文档ID
	DeleteRequest request=new DeleteRequest("ljx666","6");

	DeleteResponse updateResponse=restHighLevelClient.delete(request,RequestOptions.DEFAULT);
	System.out.println(updateResponse.status());//删除成功返回OK,没有找到返回NOT_FOUND
}

3.批量CRUD数据

        这里只列出了批量插入数据,其他与此类似
        注意:hasFailures()方法是返回是否失败,即它的值为false时说明上传成功

@Test
void testBulkAddUser() throws IOException {
	BulkRequest bulkRequest=new BulkRequest();
	//设置超时
	bulkRequest.timeout("10s");

	ArrayList<User> list=new ArrayList<>();
	list.add(new User("Java",25,new String[]{"内卷"}));
	list.add(new User("Go",18,new String[]{"内卷"}));
	list.add(new User("C",30,new String[]{"内卷"}));
	list.add(new User("C++",26,new String[]{"内卷"}));
	list.add(new User("Python",20,new String[]{"内卷"}));

	int id=1;
	//批量处理请求
	for (User u :list){
		//不设置id会生成随机id
		bulkRequest.add(new IndexRequest("ljx666")
				.id(""+(id++))
				.source(JSONValue.toJSONString(u),XContentType.JSON));
	}

	BulkResponse bulkResponse=restHighLevelClient.bulk(bulkRequest,RequestOptions.DEFAULT);
	System.out.println(bulkResponse.hasFailures());//是否执行失败,false为执行成功
}

4.查询所有、模糊查询、分页查询、排序、高亮显示

@Test
void testSearch() throws IOException {
	SearchRequest searchRequest=new SearchRequest("ljx666");//里面可以放多个索引
	SearchSourceBuilder sourceBuilder=new SearchSourceBuilder();//构造搜索条件

	//此处可以使用QueryBuilders工具类中的方法
	//1.查询所有
	sourceBuilder.query(QueryBuilders.matchAllQuery());
	//2.查询name中含有Java的
	sourceBuilder.query(QueryBuilders.multiMatchQuery("java","name"));
	//3.分页查询
	sourceBuilder.from(0).size(5);
    
	//4.按照score正序排列
	//sourceBuilder.sort(SortBuilders.scoreSort().order(SortOrder.ASC));
	//5.按照id倒序排列(score会失效返回NaN)
	//sourceBuilder.sort(SortBuilders.fieldSort("_id").order(SortOrder.DESC));

	//6.给指定字段加上指定高亮样式
	HighlightBuilder highlightBuilder=new HighlightBuilder();
	highlightBuilder.field("name").preTags("<span style='color:red;'>").postTags("</span>");
	sourceBuilder.highlighter(highlightBuilder);
		
	searchRequest.source(sourceBuilder);
	SearchResponse searchResponse=restHighLevelClient.search(searchRequest,RequestOptions.DEFAULT);

	//获取总条数
	System.out.println(searchResponse.getHits().getTotalHits().value);
	//输出结果数据(如果不设置返回条数,大于10条默认只返回10条)
	SearchHit[] hits=searchResponse.getHits().getHits();
	for(SearchHit hit :hits){
		System.out.println("分数:"+hit.getScore());
		Map<String,Object> source=hit.getSourceAsMap();
		System.out.println("index->"+hit.getIndex());
		System.out.println("id->"+hit.getId());
		for(Map.Entry<String,Object> s:source.entrySet()){
			System.out.println(s.getKey()+"--"+s.getValue());
		}
	}
}

四、总结

1.大致流程

创建对应的请求 --> 设置请求(添加规则,添加数据等) --> 执行对应的方法(传入请求,默认请求选项)–> 接收响应结果(执行方法返回值)–> 输出响应结果中需要的数据(source,status等)

2.注意事项

  • 如果不指定id,会自动生成一个随机id
  • 正常情况下,不应该这样使用new IndexRequest(“ljx777”),如果索引发生改变了,那么代码都需要修改,可以定义一个枚举类或者一个专门存放常量的类,将变量用final static等进行修饰,并指定索引值。其他地方引用该常量即可,需要修改也只需修改该类即可。
  • elasticsearch相关的东西,版本都必须一致,不然会报错
  • elasticsearch很消耗内存,建议在内存较大的服务器上运行elasticsearch,否则会因为内存不足导致elasticsearch自动killed

 

 

-----end------------

 

 

 

版权 本着开源共享、共同学习的精神,本文转载自 https://blog.csdn.net/qq_52355487/article/details/123805713 , 如果侵权之处,请联系博主进行删除,谢谢~