Gitee项目地址：https://gitee.com/linhong-java/lindaxia-es-7.6.xapi

一、客户端学习

https://www.elastic.co/guide/en/elasticsearch/client/index.html

https://www.elastic.co/guide/en/elasticsearch/client/java-rest/7.6/java-rest-high-getting-started-maven.html

二、新建SpringBoot工程

2.1.设置编译环境

2.2.调整Springboot版本

  <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.2.5.RELEASE</version>
    </parent>

2.3自定义es依赖版本

    <properties>
        <java.version>1.8</java.version>
        <elasticsearch.version>7.6.1</elasticsearch.version>
    </properties>

三、Java测试类

3.1.es客户端工具类

@Configuration
public class ElasticSearchClientConfig {
    /**
     * 注入高级客户端
     *
     * @return RestHighLevelClient
     */
    @Bean
    public RestHighLevelClient restHighLevelClient() {
        RestHighLevelClient client = new RestHighLevelClient(
                RestClient.builder(
                new HttpHost("127.0.0.1", 9200, "http")));
        return  client;
    }
}

3.2.es索引的curd

/**
 *  7.6.1高级客户端测试
 * @author: lindaxia
 * @since : create by in 2021-09-12 18:16
 */
@SpringBootTest
class EsIndexApplicationTests {
    @Autowired
    @Qualifier("restHighLevelClient")
    private RestHighLevelClient client;
    /**
     * 1.索引的创建 PUT lindaxia_index
     */
    @Test
    public void testCreateIndex() throws IOException {
        //1.创建索引请求
        CreateIndexRequest request = new CreateIndexRequest("lindaxia_index");
        //2.客户端执行请求 IndicesClient,请求后获得响应
        CreateIndexResponse createIndexResponse = client.indices().create(
                request, RequestOptions.DEFAULT);
        System.out.println(createIndexResponse);
    }
    /**
     * 2.判断索引是否存在
     * @throws IOException
     */
    @Test
    public void testExistIndex() throws IOException {
        GetIndexRequest request = new GetIndexRequest("lindaxia_index");
        boolean exists = client.indices().exists(request, RequestOptions.DEFAULT);
        System.out.println(exists);
    }
    /**
     * 删除索引
     * @throws IOException
     */
    @Test
    public void testDeteletIndex() throws IOException{
        DeleteIndexRequest request = new DeleteIndexRequest("lindaxia_index");
        AcknowledgedResponse delete = client.indices().delete(
                request, RequestOptions.DEFAULT);
        System.out.println(delete.isAcknowledged());
    }
}

3.3.es文档的curd

/**
 * @author: lindaxia
 * @since : create by in 2021-09-12 18:16
 */
@SpringBootTest
public class EsDocApplicationTests {
    @Autowired
    @Qualifier("restHighLevelClient")
    private RestHighLevelClient client;
    /**
     * 测试添加文档
     *
     * @throws IOException
     */
    @Test
    public void testAddDocument() throws IOException {
        // 创建对象
        User user = new User("林大侠", 25);
        // 创建请求
        IndexRequest request = new IndexRequest("lindaxia_index");
        // 规则 put /lindaxia_index/_doc/1
        request.id("1");
        request.timeout(TimeValue.timeValueSeconds(1));
        // 将数据放入到请求 json
        request.source(JSON.toJSONString(user), XContentType.JSON);
        // 客户端发送请求
        IndexResponse indexResponse = client.index(request, RequestOptions.DEFAULT);
        // IndexResponse[index=lindaxia_index,type=_doc,id=1,version=1,result=created,seqNo=0,primaryTerm=1,shards={"total":2,"successful":1,"failed":0}]
        System.out.println(indexResponse.toString());
        // CREATED
        System.out.println(indexResponse.status());
    }
    /**
     * 判断文档是否存在 get /index/doc/1
     *
     * @throws IOException
     */
    @Test
    public void testIsExists() throws IOException {
        GetRequest getRequest = new GetRequest("lindaxia_index", "1");
        getRequest.fetchSourceContext(new FetchSourceContext(false));
        getRequest.storedFields("_none_");
        boolean exists = client.exists(getRequest, RequestOptions.DEFAULT);
        System.out.println(exists);
    }
    /**
     * 获取文档信息
     *
     * @throws IOException {"age":25,"name":"林大侠"}
     *                     {"_index":"lindaxia_index","_type":"_doc","_id":"1","_version":1,"_seq_no":0,"_primary_term":1,"found":true,"_source":{"age":25,"name":"林大侠"}}
     */
    @Test
    public void testGetDocument() throws IOException {
        GetRequest getRequest = new GetRequest("lindaxia_index", "1");
        GetResponse getResponse = client.get(getRequest, RequestOptions.DEFAULT);
        // 打印文档的内容
        System.out.println(getResponse.getSourceAsString());
        System.out.println(getResponse);
    }
    /**
     * 更新文档信息
     *
     * @throws IOException
     */
    @Test
    public void testUpdateDocument() throws IOException {
        UpdateRequest updateRequest = new UpdateRequest("lindaxia_index", "1");
        updateRequest.timeout("1s");
        User user = new User("林大侠学java", 26);
        updateRequest.doc(JSON.toJSONString(user), XContentType.JSON);
        UpdateResponse updateResponse = client.update(
                updateRequest, RequestOptions.DEFAULT);
        // OK
        System.out.println(updateResponse.status());
    }
    /**
     * 删除文档信息（删除1号用户信息）
     *
     * @throws IOException
     */
    @Test
    public void testDeleteDocument() throws IOException {
        DeleteRequest updateRequest = new DeleteRequest("lindaxia_index", "1");
        updateRequest.timeout("1s");
        DeleteResponse updateResponse = client.delete(
                updateRequest, RequestOptions.DEFAULT);
        // OK
        System.out.println(updateResponse.status());
    }
    /**
     * 批量插入数据
     * 批量更新和批量删除
     *
     * @throws IOException
     */
    @Test
    public void testBulkDocument() throws IOException {
        BulkRequest bulkRequest = new BulkRequest();
        bulkRequest.timeout("10s");
        ArrayList<User> list = new ArrayList<>();
        list.add(new User("林大侠1", 18));
        list.add(new User("林大侠2", 19));
        list.add(new User("林大侠3", 20));
        list.add(new User("林大侠4", 21));
        list.add(new User("林大侠5", 22));
        for (int i = 0; i < list.size(); i++) {
            bulkRequest.add(
                    new IndexRequest("lindaxia_index")
                            .id("" + (i + 1))
                            .source(JSON.toJSONString(list.get(i)), XContentType.JSON));
        }
        BulkResponse bulkResponse = client.bulk(bulkRequest, RequestOptions.DEFAULT);
        //是否失败 false 则批量插入成功
        System.out.println(bulkResponse.hasFailures());
    }
    /**
     * 查询
     * 注意：name为中文 这里无法查询到结果
     *      name类型不是keyword,精确查询不是keyword只能查询单个汉字
     *
     *   SearchSourceBuilder 条件构造
     *   HighlightBuilder 构建高亮
     *   TermQueryBuilder 精确查询
     *
     * @throws IOException
     */
    @Test
    public void testSearch() throws IOException {
        SearchRequest searchRequest = new SearchRequest("lindaxia_index");
        //构建搜索条件
        SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();
        //查询条件，可以使用QueryBuilders工具类
        //QueryBuilders.termQuery 精确匹配
        //name为中文 这里无法查询到结果
        TermQueryBuilder termQueryBuilder = QueryBuilders.termQuery("age", "18");
        //MatchAllQueryBuilder matchAllQueryBuilder = QueryBuilders.matchAllQuery();
        searchSourceBuilder.query(termQueryBuilder);
        searchSourceBuilder.timeout(new TimeValue(60, TimeUnit.SECONDS));
        searchRequest.source(searchSourceBuilder);
        SearchResponse searchResponse = client.search(searchRequest, RequestOptions.DEFAULT);
        //{"fragment":true,"hits":[{"fields":{},"fragment":false,"highlightFields":{},"id":"1","matchedQueries":[],"primaryTerm":0,"rawSortValues":[],"score":1.0,"seqNo":-2,"sortValues":[],"sourceAsMap":{"name":"林大侠1","age":18},"sourceAsString":"{\"age\":18,\"name\":\"林大侠1\"}","sourceRef":{"fragment":true},"type":"_doc","version":-1}],"maxScore":1.0,"totalHits":{"relation":"EQUAL_TO","value":1}}
        System.out.println(JSON.toJSONString(searchResponse.getHits()));
        System.out.println("===========================================");
        SearchHit[] hits = searchResponse.getHits().getHits();
        for (SearchHit documentFields : hits) {
            //{name=林大侠1, age=18}
            System.out.println(documentFields.getSourceAsMap());
        }
    }
}