一、导入依赖

创建一个spring boot项目

 <dependencies>
        <dependency>
            <groupId>com.alibabagroupId>
            <artifactId>fastjsonartifactId>
            <version>1.2.78version>
        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>mysqlgroupId>
            <artifactId>mysql-connector-javaartifactId>
            <scope>runtimescope>
        dependency>
        <dependency>
            <groupId>org.projectlombokgroupId>
            <artifactId>lombokartifactId>
            <optional>trueoptional>
        dependency>
        <dependency>
            <groupId>org.springframework.bootgroupId>
            <artifactId>spring-boot-starter-testartifactId>
            <scope>testscope>
        dependency>
    dependencies>

二、创建一个配置类

这个配置类是我们获取ES的工具

package com.gsh.config;
 
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 ESConfig {
 
    //该对象可以对我们的ES进行相关的操作
    @Bean
    public RestHighLevelClient restHighLevelClient(){
        RestHighLevelClient client = new RestHighLevelClient(
                RestClient.builder(new HttpHost("127.0.0.1",9200,"http")));
        return client;
    }
}

三、ES的有关操作

1.对索引的操作

对索引的操作：

es对象.indices().相关操作

(1)创建索引

 @Test
    //创建索引
    void CreateIndex() throws Exception {
        //把该类创建的索引信息封装在该类中
        CreateIndexRequest createIndexRequest=new CreateIndexRequest("qy151-index");
        CreateIndexResponse createIndexResponse = client.indices().create(createIndexRequest, RequestOptions.DEFAULT);
        System.out.println(createIndexResponse);
    }

(2)删除索引

@Test
    //删除索引
    void deleteIndex() throws Exception{
        DeleteIndexRequest deleteIndexRequest=new DeleteIndexRequest("qy151-index");
        AcknowledgedResponse delete = client.indices().delete(deleteIndexRequest, RequestOptions.DEFAULT);
        System.out.println(delete);
    }

(3)判断该索引是否存在

 @Test
    //判断该索引是否存在
    void exitsIndex() throws Exception{
        GetIndexRequest getIndexRequest=new GetIndexRequest("qy151-index");
        boolean exists = client.indices().exists(getIndexRequest, RequestOptions.DEFAULT);
        System.out.println(exists);
    }

2.对文档的相关操作

对文档的操作:

es对象.直接操作

(1)添加一个文档

 @Test
        //添加文档
    void addWendang() throws Exception {
        IndexRequest indexRequest = new IndexRequest("qy151-index");
        indexRequest.id("2");//指定添加文档的id不指定随机生成
        //指定文档的内容:String文档的json内容，XContentType :以什么格式
        System.out.println(indexRequest.source(JSON.toJSONString(new User("张三", 24, "郑州")), XContentType.JSON));
        IndexResponse index = client.index(indexRequest, RequestOptions.DEFAULT);
        System.out.println(index.getResult());
    }

(2)查询/获取一个文档

 @Test
    //获取文档
    public void GetWendang ()throws Exception{
        GetRequest getRequest=new GetRequest("qy151-index");
        getRequest.id("1");
        GetResponse documentFields = client.get(getRequest, RequestOptions.DEFAULT);
        //获取查询到的对象
        String source = documentFields.getSourceAsString();//将获取到的结果以字符串的形式
        User user = JSON.parseObject(source, User.class);
        System.out.println(user);
 
        Map sourceAsMap = documentFields.getSourceAsMap();//将获取到的结果以map的形式
        System.out.println(sourceAsMap.get("age"));
    }

(3) 查询一个文档是否存在

@Test
    //判断文档是否存在
    void existwndang()throws Exception{
        GetRequest getRequest=new GetRequest("qy151-index");
        getRequest.id("1");
        boolean exists = client.exists(getRequest, RequestOptions.DEFAULT);
        System.out.println(exists);
    }

(4)删除文档

@Test
    //删除文档
    void deleteWendang()throws Exception{
        DeleteRequest deleteRequest=new DeleteRequest("qy151-index");
        deleteRequest.id("1");
        DeleteResponse delete = client.delete(deleteRequest, RequestOptions.DEFAULT);
        System.out.println(delete);
    }

(5)修改文档

 @Test
    //修改文档
    void updateWendang()throws Exception{
        UpdateRequest updateRequest=new UpdateRequest("qy151-index","1");
        User user=new User();
        user.setName("张学友");
        updateRequest.doc(JSON.toJSONString(user),XContentType.JSON);
        UpdateResponse update = client.update(updateRequest, RequestOptions.DEFAULT);
        System.out.println(update.getResult());
    }

(6)批量添加文档

@Test
    //批量添加文档
    public void buckWendang()throws Exception {
        BulkRequest bulkRequest=new BulkRequest("qy151-index");
        //定义一个集合用于存放批量添加的对象
        List list=new ArrayList<>();
        list.add(new Student("1","李四","男"));
        list.add(new Student("2","王五","女"));
        list.add(new Student("3","赵六","男"));
        list.add(new Student("4","徐七","女"));
        //使用Stream流
        list.stream().
                forEach(item->bulkRequest.add(new IndexRequest().id(item.getId()).source(JSON.toJSONString(item),XContentType.JSON)));
 
 
        BulkResponse bulk = client.bulk(bulkRequest, RequestOptions.DEFAULT);
        System.out.println(bulk);
    }

 (7)复杂查询

@Test
    void Search()throws Exception{
        SearchRequest searchRequest=new SearchRequest("qy151-index");
        //创建条件对象
        SearchSourceBuilder searchSourceBuilder=new SearchSourceBuilder();
        //精准查询
        TermQueryBuilder matchQuery = QueryBuilders.termQuery("name","王");
        searchSourceBuilder.query(matchQuery);
 
        //分页查找
        searchSourceBuilder.from(0);
        searchSourceBuilder.size(1);
 
        //排序查找，不能以名字作为条件
        //searchSourceBuilder.sort("age");
 
        //高量查询
        HighlightBuilder highlightBuilder=new HighlightBuilder();
        highlightBuilder.field("name");
        highlightBuilder.preTags("");//前面添加
        highlightBuilder.postTags("");//后面添加
        searchSourceBuilder.highlighter(highlightBuilder);
 
        searchRequest.source(searchSourceBuilder);
 
 
        SearchResponse search = client.search(searchRequest, RequestOptions.DEFAULT);
 
        //输出总条数
        System.out.println("总条数:"+search.getHits().getTotalHits().value);
        SearchHit[] hits = search.getHits().getHits();
        Arrays.stream(hits).forEach(iteam-> System.out.println(iteam.getSourceAsString()));
        //输出高量
        Arrays.stream(hits).forEach(iteam-> System.out.println(iteam.getHighlightFields()));
        System.out.println(search);
 
    }