SpringBoot集成ElasticSearch7.6.2进行索引操作和文档操作

ES概述

Elaticsearch简称为es， es是一个开源的高扩展的分布式全文检索引擎，它可以近乎实时的存储、检索数据；本身扩展性很好，可以扩展到上百台服务器，处理PB级别（大数据时代）的数据。es也使用 Java开发并使用Lucene作为其核心来实现所有索引和搜索的功能，但是它的目的是通过简单的RESTful API来隐藏Lucene的复杂性，从而让全文搜索变得简单。 据国际权威的数据库产品评测机构DB Engines的统计，在2016年1月，ElasticSearch已超过Solr等，成 为排名第一的搜索引擎类应用。

集成到Spring Boot

此为原生依赖

注意：elasticsearch的依赖需要与下载的ES版本一致，本次使用的7.6.2的！！！

<dependency>
	<groupId>org.elasticsearch.clientgroupId>
	<artifactId>elasticsearch-rest-high-level-clientartifactId>
	<version>7.6.2version>
dependency>

不过在SpringBoot中无需如此，直接导入

	<dependency>
		<groupId>org.springframework.bootgroupId>
		<artifactId>spring-boot-starter-data-elasticsearchartifactId>
	dependency>

也有最简单的方式，在创建SpringBoot项目时直接勾选依赖组件。

导入后的项目依赖pom.xml文件为如下，同学顺便导入jackJson方便传输数据！！

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0modelVersion>
    <parent>
        <groupId>org.springframework.bootgroupId>
        <artifactId>spring-boot-starter-parentartifactId>
        <version>2.3.1.RELEASEversion>
        <relativePath/> 
    parent>
    <groupId>top.hcodegroupId>
    <artifactId>hcode-es-api-1artifactId>
    <version>0.0.1-SNAPSHOTversion>
    <name>hcode-es-api-1name>
    <description>Demo project for Spring Bootdescription>

    <properties>
        <java.version>1.8java.version>
        
        <elasticsearch.version>7.6.2elasticsearch.version>
    properties>

    <dependencies>
        <dependency>
            <groupId>com.alibabagroupId>
            <artifactId>fastjsonartifactId>
            <version>1.2.62version>
        dependency>
        <dependency>
            <groupId>org.springframework.bootgroupId>
            <artifactId>spring-boot-starter-data-elasticsearchartifactId>
        dependency>
        <dependency>
            <groupId>org.springframework.bootgroupId>
            <artifactId>spring-boot-starter-webartifactId>
        dependency>

        <dependency>
            <groupId>org.springframework.bootgroupId>
            <artifactId>spring-boot-devtoolsartifactId>
            <scope>runtimescope>
            <optional>trueoptional>
        dependency>
        <dependency>
            <groupId>org.springframework.bootgroupId>
            <artifactId>spring-boot-configuration-processorartifactId>
            <optional>trueoptional>
        dependency>
        <dependency>
            <groupId>org.projectlombokgroupId>
            <artifactId>lombokartifactId>
            <optional>trueoptional>
        dependency>
        <dependency>
            <groupId>org.springframework.bootgroupId>
            <artifactId>spring-boot-starter-testartifactId>
            <scope>testscope>
            <exclusions>
                <exclusion>
                    <groupId>org.junit.vintagegroupId>
                    <artifactId>junit-vintage-engineartifactId>
                exclusion>
            exclusions>
        dependency>
    dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.bootgroupId>
                <artifactId>spring-boot-maven-pluginartifactId>
            plugin>
        plugins>
    build>

project>

然后编写配置文件，注入到Spring容器中

@Configuration
public class ElasticSearchClientConfig {

    @Bean
    public RestHighLevelClient restHighLevelClient(){
        return new RestHighLevelClient(
                RestClient.builder(
					//有几个集群写几个！！
                        new HttpHost("127.0.0.1",9200,"http"),
                        new HttpHost("127.0.0.1",9100,"http")
                )
        );
    }
}

SpringBoot中使用ES

注入RestHighLevelClient

    @Autowired
    private RestHighLevelClient restHighLevelClient;

创建索引

   void createIndex() throws IOException {
        //创建索引请求
        CreateIndexRequest index = new CreateIndexRequest("hcode_index"); //hcode_index为索引名
        //执行请求，获得响应
        CreateIndexResponse response = restHighLevelClient.indices().create(index, RequestOptions.DEFAULT);

        System.out.println(response);
    }

判断索引是否存在

    void ExistIndex() throws IOException {
        GetIndexRequest request = new GetIndexRequest("hcode_index");
        boolean exists = restHighLevelClient.indices().exists(request, RequestOptions.DEFAULT);
        System.out.println(exists);
    }

删除索引

void DeleteIndex() throws IOException {
        DeleteIndexRequest request = new DeleteIndexRequest("hcode_index");
        AcknowledgedResponse delete = restHighLevelClient.indices().delete(request, RequestOptions.DEFAULT);
        System.out.println(delete.isAcknowledged()); //为true表示删除成功
    }

添加文档

void AddDocument() throws IOException {
        User user = new User("hcode", 22);
        //创建索引请求
        IndexRequest request = new IndexRequest("hcode_index");
        //设置规则 例如相当于 PUT /hcode_index/_doc/1 命令
        request.id("1").timeout(TimeValue.timeValueSeconds(1));//设置id，1秒超时
        request.timeout("1s");

        // 数据转换成json 放入请求
        request.source(JSON.toJSONString(user), XContentType.JSON);

        //将请求发出去,获取响应结果
        IndexResponse indexResponse = restHighLevelClient.index(request, RequestOptions.DEFAULT);

        System.out.println(indexResponse.status()); // 返回当前操作的类型：CREATE
        System.out.println(indexResponse.toString()); //响应内容

    }

判断文档是否存在

void IsExists() throws IOException {
        GetRequest getRequest = new GetRequest("hcode_index", "1");
        // 不获取返回的_source 的上下文，会提高速度
        getRequest.fetchSourceContext(new FetchSourceContext(false));
        getRequest.storedFields("_none_");

        boolean exists = restHighLevelClient.exists(getRequest, RequestOptions.DEFAULT);
        System.out.println(exists);
    }

获取文档的信息 GET /hcode_index/_doc/1

//相当于  GET /hcode_index/_doc/1
 void getDocument() throws IOException {
        GetRequest getRequest = new GetRequest("hcode_index", "1");

        GetResponse response = restHighLevelClient.get(getRequest, RequestOptions.DEFAULT);

        System.out.println(response.getSourceAsString()); //获取文档的内容
    }

更新文档信息

void updateDocument() throws IOException {
        UpdateRequest request = new UpdateRequest("hcode_index", "1");

        request.timeout("1s");
        User user = new User("hzh", 18);

        request.doc(JSON.toJSONString(user), XContentType.JSON);

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

删除文档信息

 void deleteDocument() throws IOException {
        DeleteRequest request = new DeleteRequest("hcode_index", "1");

        request.timeout("1s");

        DeleteResponse response = restHighLevelClient.delete(request, RequestOptions.DEFAULT);
        System.out.println(response.status()); //成功返回 OK
        System.out.println(response.toString());
    }

批量操作

void BulkRequest() throws IOException {
        BulkRequest request = new BulkRequest();
        request.timeout("10s");
        ArrayList<Object> list = new ArrayList<>();
        list.add(new User("hcode", 1));
        list.add(new User("himit", 2));
        list.add(new User("youth", 3));

        //批量请求，批量更新，删除都差不多！！！不设置id就会自动生成随机id，演示为批量插入
        for (int i = 0; i < list.size(); i++) {
            request.add(new IndexRequest("hcode_index")
                    .id("" + (i + 1))
                    .source(JSON.toJSONString(list.get(i)), XContentType.JSON));
        }

        BulkResponse response = restHighLevelClient.bulk(request, RequestOptions.DEFAULT);
        System.out.println(response.hasFailures());//是否失败，false表示成功，true表示失败
    }

搜索查询+高亮

 void Query() throws IOException {
        SearchRequest request = new SearchRequest();
        //创建查询条件
        SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();
        // 使用QueryBuilders工具，精确查询term
        //QueryBuilders.matchAllQuery() 匹配所有
        TermQueryBuilder termQuery = QueryBuilders.termQuery("name", "hcode");

        //配置高亮
        HighlightBuilder highlightBuilder = new HighlightBuilder();
        highlightBuilder.field("name"); //绑定属性
        highlightBuilder.requireFieldMatch(false); //关闭多个高亮，只显示一个高亮
        highlightBuilder.preTags("
"); //设置前缀
        highlightBuilder.postTags("
"); //设置后缀
        sourceBuilder.highlighter(highlightBuilder);

        sourceBuilder.query(termQuery);
        sourceBuilder.timeout(new TimeValue(60, TimeUnit.SECONDS));

        request.source(sourceBuilder);

        SearchResponse response = restHighLevelClient.search(request, RequestOptions.DEFAULT);

        //获取结果对象
        SearchHits hits = response.getHits();

        System.out.println(JSON.toJSONString(hits));

        for (SearchHit searchHit : hits) {
            //获取高亮的html
            Map<String, HighlightField> highlightFields = searchHit.getHighlightFields();
            HighlightField name = highlightFields.get("name");

            //替换原有的字段
            Map<String, Object> sourceAsMap = searchHit.getSourceAsMap();

            if (name != null) {
                Text[] fragments = name.fragments();
                String light_name = "";
                for (Text fragment : fragments) {
                    light_name += fragment;
                }
                sourceAsMap.put("name", light_name); //进行替换
            }


            System.out.println(searchHit.getSourceAsMap());
        }
    }